Scientists have created human eggs in the lab using a similar process to the one used to clone the famous Dolly the sheep, then used in vitro fertilization (IVF) to turn them into embryos.

Although this method is far from being used in a clinical setting, the hope is that it could eventually pave the way to new fertility treatments.

"In addition to offering hope for millions of people with infertility due to lack of eggs or sperm, this method would allow for the possibility of same-sex couples to have a child genetically related to both partners," study co-author Dr. Paula Amato, a professor of obstetrics and gynecology in the Oregon Health & Science University (OHSU) School of Medicine, said in a statement.

The proof-of-concept experiment was described Tuesday (Sept. 30) in the journal Nature Communications.

The egg-making process involved removing the nucleus from an existing human egg cell and swapping it out for a nucleus from a human skin cell. This first step, called somatic cell nuclear transfer, has been used to clone a variety of animals, including Dolly.

But the OHSU researchers aimed to make a functional egg, not a clone, and eggs carry half the chromosomes as nonreproductive cells in the body do. During fertilization, an egg's 23 chromosomes combine with 23 chromosomes from a sperm cell, resulting in a total of 46. To prompt their makeshift eggs to shed half their chromosomes, the scientists applied an electrical pulse and a drug called roscovitine, which messes with enzymes that regulate the cell cycle, the process by which cells divide.

This experiment ultimately resulted in 82 egg cells that were then fertilized with sperm via in vitro fertilization (IVF), according to the statement. However, the fertilization step isn't yet foolproof — only around 9% made it to the "blastocyst" stage. At that point, the egg has divided to form a hollow sphere of cells that could be introduced to the womb via IVF.

Most of the eggs fertilized in the study didn't make it to the blastocyst stage, and in fact, only divided enough times to produce four to eight cells overall.

The "modest" blastocyst development rate likely stems from two factors, the study authors wrote in their paper. For starters, chromosomal abnormalities likely stopped the fertilized eggs from dividing further. And second, the genes swapped in from skin cells likely weren't successfully reprogrammed to sustain embryonic development. In other words, in some ways, the genes were still activating as if they were in skin cells, not the cells that form early in development.

It's unclear which issue presented the bigger problem in this study, but it's likely both factors contributed, the authors wrote.

None of the eggs that made it to the blastocyst stage were grown any further, and because they too bore chromosomal abnormalities, it's unlikely they would have been suitable for use in IVF, the researchers noted. These abnormalities included having too many or too few chromosomes, although on average they ended up with 46. Some eggs also carried multiple copies of the same chromosome or were missing certain chromosomes altogether.

So for now, the technique "is too inefficient and high risk to apply immediately to clinical application," Katsuhiko Hayashi, a stem cell researcher at the University of Osaka who was not involved in the study, told Science News.

The study authors also noted that "at this stage it remains just a proof of concept and further research is required to ensure efficacy and safety before future clinical applications."

Looking forward, the team plans to research how to better orchestrate the halving and then doubling of chromosomes within the egg. The goal would be to better capture what happens in a natural human pregnancy so that the right chromosomes are lost in the initial halving and then properly paired up with new chromosomes during fertilization.

If someday the technique can be refined for use in fertility treatment, however, it does raise ethical questions, experts told NPR. For instance, people could feasibly gather skin cells from others — including celebrities — without their knowledge and make functional eggs with them, Ronald Green, a bioethicist at Dartmouth College, told NPR. "It's a theoretical possibility, but not crazy," he said.

Other labs are working on different approaches to making eggs in the lab. Some have used stem cells to grow the eggs, either starting with stem cells or with adult cells that they then reverted back into stem cells. This approach has shown some success in mouse experiments but progress on the human front has been slower.

Scientists have created genetically engineered "woolly mice" with fur similar to the thick hair that kept woolly mammoths warm during the last ice age.

The biotechnology company Colossal Biosciences unveiled images and footage of the woolly mice on Tuesday (March 4). The adorable rodents mark a milestone in Colossal's project to bring back woolly mammoths by 2028, the company said in a statement shared with Live Science.

"We actually just started this work in mice in September [2024]," Ben Lamm, Colossal's co-founder and CEO, told Live Science. "We didn't know they were going to be this cute."

Colossal scientists plan to eventually "resurrect" woolly mammoths (Mammuthus primigenius) by first editing cells from the mammoths' closest living relatives, Asian elephants (Elephas maximus), to create elephant-mammoth hybrid embryos with shaggy hair and other woolly mammoth traits. But before the researchers can start working with elephants, they must test the relevant gene edits and engineering tools in mice, which are easier to keep and quicker to breed.

Related: Woolly mammoth de-extinction inches closer after elephant stem cell breakthrough

"A mouse model is super useful in this case, because unlike elephants [whose gestation lasts about 22 months], mice have a 20-day gestation," Beth Shapiro, an evolutionary biologist and chief science officer at Colossal, told Live Science.

The short gestation period enabled researchers to design, clone and grow the woolly mice in just six months, Lamm and Shapiro said. Colossal scientists described the results in a study that was uploaded to the preprint database BioRxiv March 4. The study has not been peer reviewed.

Fluffy rodents

To create the woolly mice, the researchers modified seven of the rodents' genes, six of which were related to fur texture, length and color. The scientists selected these genes by screening for DNA sequences that control hair growth in mice and have evolutionary links to sequences that gave woolly mammoths shaggy hair.

"We haven't taken mammoth genes and put them into a mouse," Shapiro said. "We've looked for the mouse variants of the genes that we think are useful in mammoths and then created mice that have many of these edits simultaneously."

Most of the edits "switched off" genes that are usually active in mice. For example, the scientists blocked a gene called FGF-5 that regulates hair length, resulting in mice with fur that is three times longer than standard laboratory mice.

The team also gave the mice mutations that existed in woolly mammoths, resulting in wavier fur than normal mice. Woolly mammoths had a truncated version of a gene called TGF alpha, as well as a mutation in the keratin gene KRT27, which the scientists incorporated into woolly mouse DNA.

The researchers used three genetic engineering techniques to add the edits into a single organism, including a technology called multiplex precision genome editing, which enables researchers to edit several DNA sites at once with high precision.

"It's definitely a proof of concept that you can incorporate multiple mutations into a single mouse and make its hair look like mammoth hair," Vincent Lynch, an evolutionary biologist and associate professor at the University at Buffalo who is not involved in the Colossal research, told Live Science.

Colossal scientists also focused on a gene that regulates fat metabolism and fatty acid absorption in mice. Woolly mammoths thrived in frigid temperatures in part thanks to fat deposits beneath their skin, so the team attempted to confer the same deposits onto mice by editing the associated DNA sequence.

But the effects of this insertion are unclear, Lynch said. "I guess they expected the mouse to have more or less body fat," he said, adding that the physical outcomes are likely too small to observe.

It's still unclear whether the genetically modified mice can tolerate colder conditions than standard mice, but Colossal scientists say they will test this in the coming months. "We know that the edits are in there, so now we just need to test what level of cold tolerance it confers," Lamm said.

While woolly mice are a step closer to the goal of bringing woolly mammoths back, there are still significant hurdles to overcome. For example, the technology involved in engineering the woolly mice is very advanced, but it's a far cry from what will be needed to get similar results in elephants, Lynch said. Mice have naturally dense hair, but that is not the case in elephants, meaning the technical challenge will be much greater, he said.

"Elephants have fur, but the density of the hair is much less than other mammals, so even if they could make those mutations in an Asian elephant [...] it's just going to be really sparse," Lynch said. "So what you need to do, actually, is a bunch of additional genome editing to somehow find a way to increase the density of the hair."

Science fiction, be it in the form of a book, movie, game or comic, is often a rich vein to tap for predictions of what technology could be on the horizon, or a sign as to where existing tech could go next. But you may be surprised to know that a good swath of what may seem like sci-fi actually exists in one form or another today. 

Sure, we’ve yet to find ways to jump to hyperspace or have robots take care of our every whim, but there’s a lot of technology available right now that would have seemed like the fever dream of an impassioned fiction writer only a handful of years ago. 

So here are 32 science fiction technologies that exist today — many of which you can try out for yourself.

3D printing

Star Trek’s replicator gave sci-fi fans the idea of creating things quickly out of some mystery energy/genetic material, with Captain Jean-Luc Picard barking "Tea, Earl Grey, hot."

Once total fantasy, 3D printers have made it possible to make a lot out of base polymers or even 3D print food. Modern 3D printers can create all manner of products out of polymers, metal and resin in a matter of hours, from car and vacuum cleaner components to toys, guns, models and more. And food can even be 3D printed by making use of paste-like foodstuffs such as gels and doughs.

Electric cars

The idea of cars powered by anything other than gasoline — and steam in the late 19th century — used to feel like a fantasy, with 1910’s Tom Swift and His Electric Runabout; Or, The Speediest Car on the Road envisioning an electric car that could travel 300 to 400 miles (480 to 640 kilometers) on a single charge and hit speeds of 100 mph (160 km/h). But what was fantastical 100-plus years ago is now a stone-cold reality. 

Driven forward by the likes of Tesla, modern electric cars can go hundreds of miles on a single charge and hit top speeds well in excess of 100 mph, with instant torque delivered via battery-powered motors offering huge acceleration. The only real limits to EVs are a still fledgling charging infrastructure and concerns over the lifespan of lithium-ion batteries.

Video calls and conferences

The idea of long-distance visual communications has been a staple in sci-fi for years, arguably iconified in Star Trek’s barking command of “on screen” resulting in a ship's forward window becoming a video feed of an often disgruntled alien. Fast forward a handful of decades and video calling has become commonplace in all manner of jobs where the need to be in an office or set location is no longer paramount.

The likes of Zoom, Google Meet and Microsoft Teams surged in popularity during the coronavirus pandemic of 2020, not only facilitating remote working amid lockdowns and stay-at-home directives, but also providing a social outlet for people isolated at home. 

Of course, before that the rise of smartphones and Apple’s FaceTime had already made video calling seem only moderately novel, with rapid adoption by other phone brands and technology companies democratizing video communication and conferencing for pretty much anyone with an internet connection and even a basic smartphone.

Creative AI and virtual assistants

JARVIS in Marvel’s Iron Man and Samantha from Her cemented the idea of AI-powered virtual assistants that can aid their users in everyday life; be it creating a new element or simply being around to discuss one’s love life in natural, spoken language.

With ChatGPT, Claude 3, Google Gemini and other multimodal generative AI systems, we now have smart tools that can intelligently create things rather than simply seek out existing information. This can manifest itself in asking ChatGPT to come up with a haiku based on alliteration or create images of a dog on a moon, via simple commands spoken or written in natural language. Such AIs can still be a bit hit and miss, but they open a whole new avenue to creating content even if you don’t have the requisite art or Photoshop skills, or providing a virtual friend for times when one feels lonely.

4D movies

The creepily named “Feelies” of Aldous Huxley’s 1932 Brave New World conjured up the idea of movies that are not just seen and heard, but also felt and smelt via physical feedback through the arms of a seat and via a "Scent-Organ" producing smells relating to what’s on-screen. 

Roll on 52 years and we got the first 4D movie with The Sensorium, which released scents into the theater and used bodysonic seats to provide some physical sensations. Such 4D movies and cinemas haven’t taken over from the more traditional 3D viewing experience, but improvements in sound, lighting and haptics have made them more convincing. And immersive cinema experiences from the likes of Secret Cinema can incorporate people into a movie setting in a blend of film and live action, adding an extra dimension again to the watching experience.

Driverless cars

The original Total Recall featured a taxi driven autonomously by sporting a robotic driver. What seemed fanciful in the 1990s is now a reality. No, there aren’t robot taxi drivers, but there are driverless cars. Some of these are at the trial stage, in that they are used in restricted areas for full autonomous driving. Others offer autonomous driving so long as there’s a person behind the wheel to deal with the unexpected maneuvers of fallible humans. 

Legalization and insurance hurdles are the main roadblock to a driverless car future. But with a lot of work being done in everything from autonomous driver aids to full driverless systems, the future of cars may kill the idea of an enthusiastic motorist. 

Jetpacks

An iconic moment in the James Bond film Thunderball was when Sean Connery’s Bond uses the Bell Rocket Belt to escape a villain's chateau and get to his Aston Martin DB5. Such compact jetpacks are also a dime a dozen in all manner of far-future sci-fi, but while these have yet to be created, there are some real-world jetpacks that use clusters of small-scale turbo jet engines that can be vectored to provide some form of flight. Their major limitation is fuel consumption, with flight times limited to mere minutes. 

For those with an affinity for the sea, there are jetpacks like the JetLev that use jets of high-pressure water sucked up from the sea to provide a form of flight. These aren't exactly the tools one would want at hand for escaping a building full of murderous mercenaries, but they show that jetpacks aren’t completely limited to sci-fi.

Cloning

From A Brave New World to Blade Runner and beyond, clones or replicated humans are a regular fixture in science fiction. Human cloning has yet to happen, but cloning animals is very much a reality, first established with Dolly the sheep in 1996. 

Technical obstacles — it took 270 trials to get Dolly — and ethical concerns mean directly cloning a human, called reproductive cloning, remains in the realms of fiction, and even researching techniques for doing so is illegal in many nations. However, therapeutic cloning, whereby stem cells with the same DNA as the donor are created to aid with regenerative medicine such as bone marrow transplants, is an active area of science and is being researched in nations like the U.K., Australia and China.

Humanoid robots

Robots have been around in manufacturing industries for decades, but humanoid robots that can provide a convincing human-like impression, such as those in 2004’s I, Robot, remained very much in the realms of sci-fi until recently, 

Now with Engineering Arts’ Ameca, the so-called “world’s most advanced robot” powered by generative AI, there exists a humanoid robot that can interact with people in a — mostly — near-natural manner, and pull convincing facial expressions thanks to its intricately articulated joints and a flexible, skin-like coating on a robotic skeleton. Having seen Ameca in action, the robot’s ability to create human expressions is almost uncanny. 

Robotic limbs

Many a cyberpunk novel, comic or game has explored the idea of robotic limbs as a form of human augmentation. The Deus Ex games stand out in particular, with robotic limbs being used for both curative surgery, as well as elective replacement of inferior flesh and bone body parts. 

Human augmentation hasn’t reached cyberpunk levels yet, but there are now robotic arms and hands that can carry out far more dexterous movements than prosthetics of the previous few decades. As medical science and robotics advance, we’re likely to see robotic limbs become just as capable as their biological counterparts — maybe even more so. 

Talking cars

Think about talking cars and your mind’s eye will surely think of KITT from Knight Rider. But talking cars are a reality… sort of. 

Thanks to the integration of Apple CarPlay and Android Auto into many modern cars, you can access virtual assistants like Siri and Google Assistant to respond to voice commands in natural language — modern car infotainment systems have some voice control but aren’t as sophisticated as the dedicated assistants in iPhones and Android phones. Meanwhile, chipmaker Qualcomm has its Snapdragon Digital Chassis platform, designed to bring generative AI into cars and let people have discussions with an AI about where to eat nearby and what problem a warning light on the dashboard is indicating. 

Holodecks via virtual reality

Star Trek: The Next Generation conjured up the idea of a Holodeck where the crew of the USS Enterprise could go into an expansive room that would realistically replicate all manner of settings, though commonly the crew would go back into 20th century settings or earlier. While true Holodecks have yet to arrive, University College London has the Immersive VR Lab, which lets people explore a virtual setting without the need to wear a virtual reality headset. 

But that’s more for experimental purposes. In the consumer world, a form of Holodeck exists via virtual reality headsets, ranging from simple ones that use mobile-grade chipsets to provide virtual experiences and games, such as the Meta Quest 3, to advanced headsets like the Valve Index and PlayStation VR 2 that can deliver high-fidelity virtual reality games, complete with room-scale VR, eye-tracking and advanced haptic feedback to simulate things like climbing a mountain or the tension of a taut bowstring. Such headsets can effectively turn a room into a form of Holodeck, albeit with a few limitations such as cables.

Virtual worlds

Building upon the concept of Holodecks is the idea of virtual worlds — think the simulated Earth in The Matrix. Thankfully we’ve yet to build AIs that enslave humanity as biological batteries and control them in a virtual take on the late 20th century, but we do have some fairly advanced virtual simulations. 

Games like Second Life provide virtual communities, with people exploring them via avatars and interacting with real humans. Second Like has grown to support some one million players at its peak and has seen people foster real friendships and even relationships that have resulted in real-world marriages. 

Elsewhere, sci-fi space massively multiplayer games like Eve: Online have bloomed into virtual economies with a real-life monetary value — this has seen virtual corporate wars, conspiracies and theft at a massive scale, resulting in the loss of thousands of dollars of virtual assets. And the now venerable World of Warcraft gives people a vast and evolving fantasy world to explore with interwoven quests and storylines.

Food in pills

Food in pill form is a classic staple of space-based sci-fi, but even Roald Dahl's Charlie and the Chocolate Factory featured a gum that could impart the flavors and feeling of a roast dinner. 

That level of tech remains the stuff of fiction, but food supplements and the ability to create meals by simply adding hot water to a dried food mix are the real-world parallels. And appetite suppression pills are arguably one way to help people feel full without ever taking a bite out of anything solid.

Rebreathers

Another iconic moment in Thunderball was when Bond was thrown into a shark tank and managed to escape with the assistance of a pair of tiny oxygen tanks connected to a mouthpiece. And in the maligned Star Wars: The Phantom Menace, Jedis Qui-Gon Jinn and Obi-Wan Kenobi use similar devices to dive down into the underwater cities of the Gungan.

Such tiny tanks and rebreathers are still fiction, with their size unlikely to provide much more than a few breaths in a real-world application. However, compact oxygen tanks with a mounted mouthpiece are used as emergency backups when a SCUBA aqualung runs out of air or malfunctions. Furthermore, air scrubbing and recycling can act as a form of rebreather on the International Space Station, and in the Extravehicular Mobility Units (spacesuits) used by Space Shuttle astronauts when spacewalking. 

Exo-skeletons

Powered exo-skeletons have featured in sci-fi for years, with some popular examples being the P-5000 Powered Work Loader in Alien, which Ellen Ripley uses to battle a Xenomorph queen, and more recently the exo-skeleton battle suits in Edge of Tomorrow and Elysium. 

But they exist in the real world too. Notably, the U.S. Defense Advanced Research Projects Agency’s Warrior Web program developed prototype exo-skeletons to enable soldiers to carry heavy loads. And Lockheed Martin’s Human Universal Load Carrier allows soldiers to carry loads of up to 200 pounds (91 kilograms) thanks to the use of titanium legs and onboard computers to mimic human movements.

Nuclear-powered vehicles

In 1914, H.G. Wells’ The World Set Free envisioned vehicles running on atomic power, and more recently the Fallout game and TV series ran with his idea, with an alternative history that saw the Atomic V-8 car powered by a nuclear fusion engine. 

Now, while nuclear fusion-powered cars are theoretically possible, safely shrinking a reactor to car engine size is a technical challenge that humans have yet to overcome. However, we do have nuclear-powered vehicles in the form of nuclear submarines and ships. For example, the USS Enterprise aircraft carrier that operated up until 2012 was powered by an unprecedented eight nuclear reactors. And the U.K.’s Royal Navy's Vanguard Class submarines make use of a Rolls-Royce PWR 2 reactor. Unlike their land-based equivalents, these marine reactors use a metal-zirconium alloy rather than ceramic uranium dioxide as fuel, with the goal of having a long core life, so that refueling is only needed after 10 years or more.

Living in space

OK, so the ideal of living in space under giant domes or in vast space stations such as Star Trek’s Deep Space Nine are far from reality. But humans have been living in space for decades, notably with the International Space Station. 

A joint effort between the space agencies of the U.S., Russia, Japan, Europe and Canada, the ISS can support astronauts and scientists living in the zero gravity of space while orbiting Earth. Solar panels harvest energy, while supply runs via space shuttles and unmanned rockets keep people in the ISS alive. Resistance training is needed to keep muscles from atrophying in zero-g and the space station is far from self-sufficient, but the ISS does provide a gateway to living in space.

Railguns

Featured a lot in so-called hard sci-fi, railguns can be found mounted on spaceships like The Expanse’s Rocinante, the Daedalus in Stargate, and a lot more. Also known as gauss guns or mass drivers — such as the mass accelerator guns in BioWare’s space opera games Mass Effect — railguns work around the idea of using electromagnetism to accelerate a slug along twin rails, bypassing the need for a combustible accelerant like gunpowder. In fiction, these weapons are generally line-of-sight, firing unguided tungsten rounds at targets within a range where the shot can’t be easily dodged. 

Actually first conceived in 1879 as an electric cannon, functional railguns didn't become a reality until 2010, when BAE Systems developed one capable of firing a 7 lb (3.2 kg) projectile at 3,390 m/s. This used the same concept as the sci-fi equivalents, and saw the U.S. Navy flirt with railgun development until 2021, when it shelved the project. 

Other nations like Japan are also looking into developing rainguns. However, the biggest drawback is the huge energy needed to accelerate a slug. As such, gunpowder-based shells with large caliber guns are still used for close-quarters ship combat. Equally, there are consumer railguns that use electromagnets to accelerate small metal discs. Again, the charge they deliver doesn’t make them effective combat weapons; instead they are more niche guns for casual target practice. 

Space tourism

Exploring the stars is likely the fantasy of many people who’ve looked up at a star-studded sky on a clear night. But with a lack of an efficient fusion engine or faster than light travel, the sci-fi idea of space tourism — adventures to spa facilities on Titan or the joys of Starfield’s Neon city — are still stuck in fiction.

But a form of space tourism does exist, in the guise of Virgin Galactic, whereby a specially-designed ship can take a handful of people to the sub-orbit of Earth — near enough space with low gravity and all. Just be aware you need a spare $450,000 and likely a direct line to Sir Richard Branson.

Stealth tech

Star Trek’s Klingons and their Bird of Prey ships are iconic for their ability to cloak and avoid detection by the likes of the USS Enterprise. The idea here is that the ship can bend light around it to become invisible. In more realistic sci-fi, stealth is less about being invisible than about hiding a ship’s heat signature and radar profile, as seen in Mass Effect’s Normandy stealth frigate and the angular Anubis class stealth frigates in The Expanse. 

Currently, humanity has no spacefaring stealth ship, but stealth ships and craft are very much real. The U.S. navy’s experimental Sea Shadow (IX-529) used an angular design to give it a low-radar profile in order to avoid detection, while the French frigate Forbin has a faceted appearance to reduce its radar cross-section. 

Stealth aircraft work in a similar way, with passive low observable features to minimize their radar profile, while they also use surfaces that can absorb radar energy, preventing it from being bounced back to a receiver.

Smartwatches

Dick Tracey and the likes of Thunderbirds introduced the idea of being able to speak into a watch, even one with video displayed, while the Seiko G757 Sports 100 watch in James Bond film Octopussy, could display messages from MI6 on a small digital display. 

These days this all seems very basic, thanks to smartwatches, led by the Apple Watch. Not only can calls be handed via these watches, the latest smartwatches can track your health metrics, intelligently assess your physical performance, act as an organizer of daily life, control smart home gadgets and more. In the nine years since the original Apple Watch was launched, smartwatches have evolved from phone accessories into wearable computers that arguably eclipse even much of what sci-fi envisioned.

Smartphones

The idea of handheld, do-everything computing devices is a staple in sci-fi, with the likes of Star Trek’s Tricorders purportedly being the inspiration for flip phones. But the hand terminals of The Expanse series are smartphones that have the ability to spool through cross-solar system news feeds and alert people to take specific medication. 

Modern smartphones are arguably rather sci-fi devices in themselves, as they’re basically computers in slim, pocketable, rectangular form. Even budget phones are now capable of putting nearly any information you can imagine at your fingertips, as well as being a portable camera, video editing suite, games console, streaming device, media player, smart tech controller, productivity tool, home for an AI and a lot more. And now some of them fold.

Real-time translation

Universal translators, up to and including the Babel Fish in Douglas Adams’ Hitchhiker’s Guide to the Galaxy, have long been a way for sci-fi to handwave away the problems of communication between “advanced” extraterrestrial lifeforms. However, thanks to Google Translate and now AI-powered translation apps and tools, we are approaching a reality where universal real-time translation is a district possibility. 

Right now, translation tools in phones like the Samsung Galaxy S24 can provide two-way audio translation of speech in select languages. We still need to discover extraterrestrial life before we can have the universal translators of sci-fi, but we have the rudiments of the technology. 

Targeted advertising

Minority Report envisioned targeted advertising dynamically adjusting ads to suit your interests back in 2002. Around a decade later, it became a reality. As you read this very article you’ll have likely encountered so-called cookies that can scrape what you’ve searched for on your computer or phone’s browser and serve up adverts that are (or should be) relevant to your browsing. 

This has evolved with apps like Google Maps serving up places you might be interested in visiting based on your trips and wandering, while algorithms in streaming services like Netflix and Spotify work to flag content they think is relevant to your tastes.

Sometimes today’s targeted advertising can be uncanny, with the feeling that a conversation you’ve had with friends about a holiday suddenly results in adverts about vacation services popping up on Instagram. However, there's no evidence of such apps being quite that advanced — and users can, thankfully, opt out of targeted advertising. 

Drones

1974’s Danny Dunn, Invisible Boy featured what was basically a drone, in the form of a tiny flying device packed with sensors that could be flown remotely. Now, some 40 years later, consumer drones are very popular, used to take photos and videos that would have previously needed a helicopter, or simply piloted around for fun. Furthermore, drone racing is a legitimate sport and drones can be had in all sizes. 

On the more sinister side, drones are used for military purposes, not only to deliver explosive payloads in a form of a bootstrapped pilotable bomb, but also as dedicated unmanned aerial vehicles armed with cutting-edge guns and missiles that well-equipped militaries can send into a battle zone without the need to risk manned aircraft. With drones being considered for delivery of goods and not just offensive payloads, expect drone use only to expand as this decade marches forward.

Mass surveillance

George Orwell’s 1984 envisioned a dystopian world where people could be watched by the governing powers in their own homes. While this has yet to happen in daily life, U.K. TV show Big Brother borrows from Orwell’s overseeing antagonist and puts willing contestants into a house where they are isolated from the outside world and are constantly monitored by the all-seeing-eye “Big Brother,” who also directs them to do various, often humiliating tasks.

This is entertainment, but mass surveillance also happens in a very real way in daily life. We now live in cities with interconnected surveillance cameras feeding into hub systems. Currently used predominantly as a crime prevention and law enforcement tool, as well as a way to monitor footfall, this level of surveillance can easily track suspicious people from street to street, acting as an eye-in-the-sky guide for police and security. Beijing and London are two of the most-surveilled cities in the world, with the latter having some 67 CCTV cameras per 1,000 people. 

Flying cars

The Jetsons seeded the idea that flying cars are the future, but while electrification of power trains was explored in the past few decades, the idea of flying cars had seemed pie-in-the-sky. 

Yet in recent years more concepts for short-range, electric vertical takeoff and landing (VTOL) taxis and cars have popped up, with many looking set to become a reality this decade. We currently have the technology for somewhat efficient flying cars, but safety, legal and insurance hurdles currently stand in the way, though nations like the U.S. and China are working on establishing guidelines for safe, legal flying cars in the next decade. 

Wireless earbuds and communication

From Star Trek’s ComBadge to James Bond gadgets, the idea of wireless communication via a form of wearable device, mostly earbuds, permeates a lot of sci-fi. But the advent of Apple’s AirPods wireless earbuds galvanized not only cable-free audio but also wireless, hands-free communication. 

The latest iterations of wireless earbuds and headphones contain all manner of smart technology, from active noise cancellation to touch-sensitive controls and movement detection. And now we have bone conduction audio that allows one to receive audio via devices like smart glasses without the need for in- or over-ear headphones. 

World Wide Web

While the concept of the internet existed before William Gibson’s 1984 Neuromancer, the novel is credited with popularizing the term “cyberspace” and envisioned a global network of connected computers transferring information in a graphical interface. If this sounds familiar it’s because that’s the premise of the World Wide Web we have today, though back in the 80s when personal computers were a novel idea, the concept of such linked technology and information highways was science fiction. 

That really started to change in the 1990s, when the Web opened to the public. It has since blossomed to become the place where one can access pretty much the sum total of human knowledge, masses of entertainment, content both pure and sordid, and a whole lot more. Tim Berners-Lee’s invention may have seemed like sci-fi but has changed the way information is consumed, and economies and even societies are influenced at an unprecedented scale and pace; often for the better, but at times for ill.

Synthetic and plant-based meat

Both Bethesda’s Starfield space-exploration epic and the hard sci-fi of James S.A. Corey’s The Expanse series feature synthetic meat, with the idea being that getting fresh, real beef or pork out in deep space would be a logistical nightmare. 

But the idea of using either cultured meat proteins or alternative proteins to replicate meat is very much a reality today. Impossible Foods made waves in recent years by creating a beef burger out of soy protein that mimics the look, feel and flavor of real beef, with many people swearing they can’t tell the difference. 

And vegan food company Beyond Meat makes readily available, plant-based products that aim to replicate the flavor of their real meat counterparts, though discerning palates can still taste the difference between the real and fake. 

While we may hit a limit to how closely vegan foods can replicate real meat, lab-grown meat is being explored as an alternative to the traditional rearing and slaughtering of animals. This process grows meat from real animal cells, thus producing real meat — just without killing a pig or cow. Companies like Eat Just already sell cultured meat, but the problem is producing it at scale at an affordable price; expect things to develop over the next decade.

Household robots

Robot butlers and house-based bots are a staple of science fiction; a recent example being the Codsworth robot in the Fallout TV show and games. While we’ve yet to get humanoid robots to serve us martinis at leisure, many of us do have robots in our homes right now. 

Mostly, these come in the form of robot vacuum cleaners and grass mowers, many of which have advanced tracking and automation regimes so that you can simply leave them to their tasks. But there are also robot pets, most notably Sony’s AIBO robot dog, which can respond to voice commands and sense when it’s being petted. And Amazon’s Astro aims to be an automated home monitoring robot, complete with Alexa built-in to respond to natural language commands.

Scientists have made a stem cell breakthrough in elephants, which could mean researchers are one step closer to bringing back long-extinct woolly mammoths, the de-extinction company Colossal Biosciences has announced.

In a statement shared with Live Science, Colossal's Woolly Mammoth team says it has successfully derived induced pluripotent stem cells (iPSCs) from Asian elephants (Elephas maximus). iPSCs are cells that have been reprogrammed so they can give rise to any cell type in the body, meaning researchers will now be able to investigate the adaptations that differentiate woolly mammoths (Mammuthus primigenius) from their closest living relatives and test gene edits without having to take tissue from living animals.

"These cells definitely are a great benefit to our de-extinction work," Eriona Hysolli, the head of biological sciences and mammoth lead at Colossal Biosciences, told Live Science. What's crucial about them, Hysolli said, is that they can reveal the cellular and genetic processes behind features that helped woolly mammoths thrive in the Arctic. These features include shaggy hair, curved tusks, fat deposits and a dome-shaped cranium. 

iPSCs also open a path to creating elephant sperm and egg cells, which are essential for mammoth de-extinction, in the lab. With fewer than 52,000 Asian elephants left in the wild, according to WWF, harvesting cells from these animals would prove difficult and undesirable.

Previously, deriving elephant iPSCs proved challenging because these animals have a complex gene pathway not found in other species. The researchers overcame this by suppressing core genes called TP53 that regulate cell growth and prevent cells from duplicating indefinitely, Hysolli said.

Related: 'That's a huge amount of movement for a single mammoth': Woolly female's steps retraced based on chemistry of 14,000-year-old tusk

"One of the things that we had to overcome for elephant cells is that they do have this expansive TP53 pathway," Hysolli said. "We had to suppress this pathway via two means in order to get these iPSCs, so we had to go through a multistep process in order to achieve them."

The breakthrough may also shed light on early development in elephants, which is currently considered the biggest hurdle to woolly mammoth de-extinction. If researchers succeed in creating a woolly mammoth embryo by fusing ancient mammoth DNA with elephant cells, they will need to implant this embryo into an elephant surrogate to complete a 22-month gestation period. "Elephant gestation is so long and complex, so really understanding the developmental biology aspect of elephant biology is so important," Hysolli said. 

Engineering a woolly mammoth embryo no longer poses a huge challenge, Hysolli said, but birthing a healthy calf will take more time and work. The team is still researching alternative methods to generate elephant iPSCs and maturing the ones they have newly developed. The iPSCs breakthrough, which will be published on the preprint database bioRxiv, has yet to be peer-reviewed.

"There is more validation to be done, so until you do the experiment you can never be sure, but we think that the pluripotency potential [to differentiate into any cell type] is fully there," Hysolli said.

This is an important breakthrough and an essential step to create a woolly mammoth-like elephant, said Vincent Lynch, a developmental biologist and associate professor at the University at Buffalo in New York who was not involved in Colossal's work. "The goal, I think, is to turn these iPSCs into sperm and eggs, which would allow for in vitro fertilization and, eventually, surrogacy," Lynch told Live Science in an email. "Those methods are pretty challenging and haven’t been developed yet, but it is only a matter of time."

Reprogramming elephant cells into iPSCs has applications beyond woolly mammoth de-extinction, according to the statement. The technology could provide a boost to elephant conservation, for example, by enabling researchers to produce and fertilize reproductive cells artificially.

"We can derive gametes, so oogonia and spermatogonia-like cells, from these pluripotent stem cells," Hysolli said. "And that's crucial over the longer term, because they can really hold the key to saving species."

Two Przewalski's horses  have been successfully cloned using DNA from a long-dead male, which may have significant implications for the critically endangered species. 

The San Diego Zoo Wildlife Alliance announced the birth of the second foal in September 2023. Now scientists have documented the cloning process in a new study, published Dec. 21, 2023 on the preprint server BioRxiv. 

Native to the steppes of Central Asia, Przewalski's horse (Equus przewalskii or E. ferus przewalskii) has long been considered the only remaining species of wild horse. Some experts consider it to be its own species, while others consider it to be a subspecies of the extinct Equus ferus, the wild horse from which domestic horses are likely descended. 

Przewalski's horses once roamed across western Europe and central Asia. But their populations began to plummet due to a variety of factors, including agricultural competition, human conflicts and brutal winter conditions. Populations were already diminished when the species was first described in the late 19th century.

The last known truly wild Przewalski's horse was sighted in 1969 in Mongolia, and it was declared extinct in the wild in the 1980s. Now, only around 3,000 remain in captive populations and reintroduced herds. The current population is descended from 13 foals captured in the wild between 1899 and 1902 — the only reproducing members of the 53 horses originally distributed to zoos.

Related: How does cloning work?

A formal breeding program began in 1959. However serious inbreeding issues resulted from the scant original population — a situation that was slightly alleviated by introducing a small number of domestic horses to the gene pool.

Przewalski's horses were reintroduced to the wild in June 1992 in Mongolia's Hustai National Park. Additional herds have since been reintroduced in China, Hungary, Kazakhstan and Russia.

In 2018, the San Diego Zoo Wildlife Alliance collaborated with Revive & Restore and pet cloning company ViaGen Pets and Equine to introduce much-needed genetic diversity into the existing population.

Scientists generated the two cloned horses using genetic material from a male known as Kuporovic that died in 1998. His donor cells had been preserved in 1980.

They selected Kuporovic as the cell donor because he was the most genetically distant from all other males in the Przewalski's horse studbook — the list of horses that had been bred in the past. 

Kuporovic did have some domestic horse ancestry — but this would have little impact in terms of conservation, lead author Ben J. Novak, a de-extinction biologist with conservation organization Revive & Restore, told Live Science. 

"Genetic 'purity' in the history of Przewalski's horse conservation is an arbitrary construct influenced heavily by human culture and pseudoscience," he said. "Modern genomics has revealed that hybridization is very common in nature, and not only beneficial in many circumstances but also has played an essential role in the evolution of many species."

The two horses were cloned by fusing cells from the donor horse with oocytes (ovarian cells) from domestic mares by applying an electrical pulse. The artificially fertilized egg then began developing into an embryo just as a normally fertilized egg would. 

Ethicists have raised concerns about the potential health problems in cloned animals. Dolly, the famous cloned sheep, lived to be only 6 years old, about half the normal lifespan of a sheep. But other cloned sheep appear to be living normal lifespans, so the frequency of negative effects due to the cloning process remains unclear.

"Currently, we have no reason to believe that cloned Przewalski's horses are different from naturally conceived Przewalski's horses," Novak said.

More broadly, the success of "resurrecting stallions" via cloning could help to "undo some of the genetic erosion" caused by breeding from zoo populations, the authors wrote. 

Scientists in China have successfully cloned a rhesus monkey by providing the cloned embryo with a healthy placenta. The innovative technique could significantly increase the success rate of cloning, the researchers say.

The monkey, named ReTro, is now three and a half years old and still "doing well and growing strong," study co-author Qiang Sun, a primate neuroscientist at the Chinese Academy of Sciences' Center for Excellence in Brain Science and Intelligence Technology, told Live Science in an email.

Researchers have cloned rhesus monkeys before, but this is the first success using a method known as somatic cell nuclear transfer, which involves replacing the nucleus of a fertilized egg cell with a nucleus extracted from another individual's somatic cells. (Somatic cells include every cell in the body except reproductive cells.) A previous attempt to clone a rhesus monkey using somatic cell nuclear transfer resulted in a live birth, but the infant died just 12 hours later. 

Rhesus monkeys (Macaca mulatta), also called rhesus macaques, are commonly used in laboratory experiments and medical research because they are genetically very closely related to humans. Creating clones of these monkeys "can help us to obtain non-human primate models with identical genetic backgrounds and genotypes [to each other] in a short time," Sun said. This would help researchers filter out any effects of genetic variation between models when testing drugs, for example.

Related: Scientists want to clone an extinct bison unearthed from Siberian permafrost. Experts are skeptical.

The successful cloning, which was described in a new study published Tuesday (Jan. 16) in the journal Nature Communications, is a step toward improving cloning efficiency in primates and other mammals, Sun said.

Scientists have used somatic cell nuclear transfer to clone a range of different mammal species, such as other monkeys, sheep (including Dolly the sheep), cattle and dogs. Most cloned embryos don't survive to birth, however, often due to defects in the development and structure of the placenta. Between 1% and 3% of attempts result in a live birth using conventional cloning methods, according to the study, although the success rate is slightly higher in cattle (5 to 20%). 

To overcome this problem, Sun and his colleagues replaced a cluster of cells that normally develops into the placenta from the cloned embryo with the same cells from a normal embryo. These cells, known collectively as the trophectoderm, formed a healthy placenta that provided the cloned embryo with nutrients and oxygen during development. The experiment resulted in the birth of a healthy male rhesus monkey in 2020.

"This approach significantly increased the success rate of cloning by somatic cell nuclear transfer," Sun said, and it could yield "a higher number of cloned animals using a reduced number of oocytes," or egg cells.

"As placental defects are commonly seen in all cloned mammal species, we anticipate that it might be applicable in other mammals and non-human primates," Sun added.

Sir Ian Wilmut, the scientist who led the cloning of Dolly the sheep, has died at the age of 79.

Wilmut led the University of Edinburgh team that successfully created Dolly, the first mammal to be cloned from an adult cell, in 1996. 

Other researchers had managed to clone mammals by splitting embryos in a test tube and implanting them in adults. But Dolly — named after the singer Dolly Parton — was cloned from the mammary gland of a 6-year-old Dorset Finn ewe and was the first to be grown from an adult somatic (body) cell.

Related: Single bee is making an immortal clone army thanks to a genetic fluke

In 2017, Wilmut revealed that he had been diagnosed with Parkinson's disease.

"We are deeply saddened to hear of the passing of Professor Sir Ian Wilmut. He was a titan of the scientific world," Sir Peter Mathieson, principal and vice-chancellor of the University of Edinburgh, said in a statement. 

Mathieson added that Wilmut's breakthrough "transformed scientific thinking at the time" and "continues to fuel many of the advances that have been made in the field of regenerative medicine that we see today." 

How was Dolly the sheep cloned?

Animals had been cloned from somatic cells before Dolly, notably frogs cloned from skin cells in 1958 by British biologist John Gurdon. But Dolly was significant because decades of failed attempts had made biologists think that the process in mammals was all but impossible.

The scientists made Dolly by extracting DNA from a cell taken from an adult sheep's mammary gland, placing it in an empty sheep egg cell and zapping it with electricity. This transformed the egg into an embryo, which was then implanted inside a surrogate sheep to bring to term.

The breakthrough led to an explosion of research into stem cells and their medical applications.

Following Dolly's July 1996 birth, pigs, deer, rats, bulls, horses and macaques were successfully cloned, and scientists soon began inducing stem cells to grow into a vast array of tissue types — driving stem cell therapy for genetic diseases into the mainstream.

How long did dolly the sheep live?

Dolly died in 2003 after living to age 6, around half the typical 10-to-12-year lifespan of a sheep, and had a number of clone sisters taken from the same batch of cells as her.

"The birth of Dolly and the new understanding of the opportunity to change the functioning of cells made researchers consider other possible ways of modifying cells," Wilmut told Live Science in 2017.

Following his work on Dolly, Wilmut continued to genetically engineer and clone sheep in an effort to make stem cells and create milk with proteins that could treat human diseases.

Wilmut retired in 2012, and received a knighthood in 2008. Following his Parkinson’s diagnosis, he took part in the testing of new types of treatments for the degenerative disease.

Researchers in Russia recently completed a necropsy, or animal autopsy, on a stunningly intact extinct bison that was unearthed from Siberian permafrost. The tissues recovered during the dissection are so well preserved, the team believes the long-dead specimen could be cloned.

But one expert told Live Science that it is a long shot.

The mummified creature, which belongs to an unknown species of extinct bison, was discovered at the Khaastaakh locality in the Verkhoyansk region of Russia in summer 2022 and donated to the Mammoth Museum Laboratory of North-Eastern Federal University (NEFU) in Yakutsk. Preliminary investigations revealed that the bison was a juvenile of unknown sex that was between 1 and 2 years old when it died. Scientists don't know yet when the bison lived, but similar specimens found in 2009 and 2010 dated to between 8,000 and 9,000 years ago, NEFU researchers wrote in a statement. 

During the necropsy, researchers took samples of the bison's wool, skin, bones, muscles, fat and horns, as well as completely removing the animal's brain. The tissues are so well preserved that there is hope they could be used to revive the extinct species.

Related: The CIA wants to bring back woolly mammoths from extinction

"We are working with a unique find that could be cloned in the future thanks to selected materials," Hwang Woo Suk, a former cloning expert and NEFU collaborator, said in the statement. (Hwang was fired from the University of Seoul National University in South Korea in 2006 and narrowly avoided jail time after faking results and breaking bioethics rules while attempting to clone embryonic human stem cells.)

The researchers want to return to where the bison was found to look for other specimens that could help them revive this lost species. However, not everyone is convinced that ancient bison can be cloned.

"In my view, it is not going to be possible to clone extinct animals from tissues like this," Love Dalén, a paleogeneticist at Stockholm University in Sweden who was not involved in the necropsy, told Live Science in an email. Although the tissues are exceptionally well preserved, the DNA within them is likely too degraded to be cloned, he added.

"To make cloning possible, one needs to find intact chromosomes, but what we see even in the best specimens is that each chromosome is fragmented into millions of pieces," Dalén said. "In my view, it is more likely that you can flip a coin and get heads a thousand times in a row than it is to find an intact chromosome from a specimen that is thousands of years old." (Chromosomes are thread-like structures made up of DNA that are found in a cell's nucleus.)

However, it may be possible to sequence a majority of the bison's genome, which could be combined with DNA from other specimens of the extinct species as well as living bison to eventually revive the extinct animal, Dalén said. This would still be extremely difficult, but the likelihood of success is "many orders of magnitude higher" than directly cloning the specimen, he added.

NEFU scientists also recently dissected a mummified bear unearthed on a remote Russian island that they thought belonged to an extinct species of cave bear dating back to 22,000 years ago, but the specimen turned out to be a 3,500-year-old brown bear instead.

A Chinese pet-cloning company has announced the birth of the world's first cloned Arctic wolf (Canis lupus arctos), which was carried to term by an unlikely surrogate mother — a beagle.  

The cloned female wolf pup, named Maya, and her beagle mother were unveiled to the world in a brief video at a press conference held Sept. 19 by the Sinogene Biotechnology Company in Beijing, according to Chinese news site Global Times. The video was released 100 days after Maya was born: on June 10 in a laboratory in Beijing, according to Sinogene representatives. 

Normally, Sinogene specializes in cloning dead pets, such as cats, dogs and horses, for private clients. But the company now wants to use its expertise to help clone endangered species for conservation purposes, Global Times reported.  

Maya was cloned using DNA collected from a fully grown Arctic wolf, also named Maya, that died in captivity at Harbin Polarland, a wildlife park in northeast China. The original Maya, who was born in Canada before being shipped to China in 2006, died due to old age in early 2021, according to Global Times.  

Related: Why haven't we cloned a human yet? 

The cloning of Maya was successfully completed "after two years of painstaking efforts," Mi Jidong, general manager of Sinogene, said at the company's press conference, according to Global Times.    

Sinogene researchers originally created 137 Arctic wolf embryos by fusing skin cells from the original Maya with immature egg cells from dogs, using a process known as somatic cell nuclear transfer (SCNT). Of those embryos, 85 were successfully transplanted into seven beagle surrogates. From those transplanted embryos, just one fully developed during pregnancy, according to Global Times.

The researchers used beagle surrogates because there were not enough female wolves in captivity for the scientists' experiments. Luckily, dogs share enough DNA with wolves for the hybrid pregnancy to gestate successfully.

Maya now lives with her surrogate mother at a Sinogene lab in Xuzhou, eastern China, but the wolf pup will eventually be transferred to Harbin Polarland to live with other Arctic wolves. However, the park's keepers believe she will have to be slowly introduced to the rest of the pack because of her isolated upbringing, according to Global Times. 

Sinogene also revealed that a second Arctic wolf clone, created using DNA from an unknown male, was due to be born Thursday Sept. 22. However, there have been no confirmed reports so far of the pup's birth.

The company also announced a new partnership with the Beijing Wildlife Park to clone more captive species in the future, although no specific projects have yet been announced, according to Global Times. 

In 2019, Sinogene was also involved with a project that produced six identical German shepherd clones, which were then inducted into the Beijing police force, according to CBS News. 

Cloning endangered animals 

Despite reports from Global Times and other media outlets, Arctic wolves, which are a subspecies of gray wolves (Canis lupus) are not an endangered species. Instead, they are listed as least concern by the International Union for Conservation of Nature, though climate change is likely to severely disrupt their food supply in the wild in coming decades, according to WWF.

But endangered species have been cloned by scientists before.  

In 2020, scientists from U.S.-based non-profit conservation organization Revive & Restore successfully cloned an endangered black-footed ferret (Mustela nigripes). That same year, the company also successfully cloned an endangered Przewalski’s horse (Equus przewalskii), and their technicians are now attempting to revive the extinct passenger pigeon (Ectopistes migratorius) using cloning technology.

"Cloning is a drastically underutilized tool," Ben Novak, lead scientist at Revive & Restore, told Live Science in an email. "In the future, it could be a literal lifeline for species that become rarer or worse, go extinct."

The main benefit of cloning endangered species is that it maintains the amount of genetic diversity within a species, Novak said. If the clones can reproduce with other non-cloned individuals, this gives threatened species a fighting chance to adapt to the selection pressures that are driving them towards extinction, he added.  

Another benefit of cloning is that it can be used in conjunction with existing captive-breeding programs, especially when surrogate mothers from other species are used, Novak said. Rather than taking animals from the wild to create a back-up population in captivity, scientists can take genetic samples from wild animals and create clones in the lab using more readily available surrogates, as they did with Maya and her beagle mother. These genetic backups can then be introduced into the wild to replenish struggling populations, Novak said.   

"For mammals, it appears that two species must share a common ancestor less than 5 million years ago" for the surrogate pregnancy to be successful, Novak said. This opens up the possibility of reviving extinct species by using closely related living surrogate species, he added.

Related: Is it possible to clone a dinosaur?

However, there are also some major limitations to cloning. 

One of the main issues is that not all animals can be successfully cloned yet. To date, only mammals, fish, amphibians and a single insect species have been cloned using SCNT, Novak said. For birds, reptiles and egg-laying mammals, like platypuses and echidnas, SCNT does not work because the eggs do not properly develop, he added.

Cloning also has a very low success rate compared with artificial insemination or in-vitro fertilization, Novak said. As with Maya the wolf pup, researchers often have to create hundreds of embryos and successfully implant them in multiple surrogates for just one animal to be born, which can make cloning an expensive process.

Due to these high costs, the emergence of private entities like Sinogene and Revive & Restore will likely play a key role in the future of conservation cloning. Historically, most cloning research has been done by universities that are underfunded, Novak said. Therefore, "the partnership of for-profit companies with conservation programs is key to turning cloning from a seldom-researched technique into a valuable conservation tool."

For cloning advocates, the birth of Maya is another step in the right direction for this area of research.

"It's great to see more wildlife cloning work being done," Novak said. "I hope all these recent achievements in cloning show the world that cloning is ready to use as a beneficial tool for wildlife conservation."

Originally published on Live Science.

Scientists have discovered the world's biggest clone in Australia: A massive network of seagrass meadows that covers more than 77 square miles (200 square kilometers). The network of meadows is actually one single plant that has been continually cloning itself for almost 4,500 years. 

Researchers found the enormous clone while studying the genetic diversity of seagrasses in Shark Bay, a protected body of shallow water in Western Australia. They learned that almost all the region's meadows of Poseidon’s ribbon weed (Posidonia australis) are genetically identical. Further analysis revealed that unlike the other seagrasses in the area, which reproduce sexually, P. australis is actually cloning itself through an underground network of branching roots.

The P. australis clone stretches for around 112 miles (180 km) from end to end — albeit with a few patches — "making it the largest known example of a clone in any environment on Earth," the researchers wrote in the study, which was published online May 31 in the journal Proceedings of the Royal Society B. It dwarfs the previous record-holder: a clone of the seagrass Posidonia oceanica in the western Mediterranean, which spans around 9 miles (15 km).

"It is a single plant" that has been able to grow uninterrupted, senior researcher Elizabeth Sinclair, an evolutionary biologist at the University of Western Australia, told Live Science. If it remains undisturbed, the gigantic clone could continue to expand indefinitely, Sinclair added, making it practically immortal.

Related: 24,000-year-old 'zombies' revived and cloned from Arctic permafrost 

Clonal expansion 

The researchers found that the P. australis clone was expanding through a process known as "horizontal rhizome extension," in which a plant creates a genetically identical offshoot via an underground stem, or rhizome, which then develops its own roots and stem. When viewed from the surface — in this case, the sandy seafloor — the seagrass clumps look like separate specimens, but on a genetic level they are the same plant.

This is the same process that birthed Pando, a forest of quaking aspen trees (Populus tremuloides) in Utah that is actually just one massive, interconnected tree. 

While the P. australis meadows do not form a single unbroken meadow, they can still be considered to be one plant, Sinclair said. "Seagrass plants can fragment over time if there is damage or disturbance, but the fragments are still genetically identical," she added. It is possible that the P. australis meadows were once fully connected and may have been fragmented by grazing marine animals or extreme heat waves, the researchers wrote in the study. 

Based on the size and age of the P. australis meadows, researchers suspect that the clone is growing at a rate of around 6 to 14 inches (15 to 35 centimeters) per year. This may not sound like much, but it's a fairly quick rate when compared with the growth of other clonal seagrass meadows, the study authors reported. 

Theoretically, the clone could continue to grow indefinitely, Sinclair said, "as long as it's not disturbed and the environment doesn't change too quickly." The near-pristine conditions in Shark Bay, which was designated in 1991 as a World Heritage Area by the United Nations Educational, Scientific and Cultural Organization (UNESCO), mean that P. australis has remained relatively undisturbed throughout its entire life, she added. 

Genome duplication 

The researchers suspect that another part of the P. australis success story can be attributed to an unusual genetic superpower among plants that enables them to make an additional copy of their genome, which doubles the amount of DNA they can utilize to adapt to extreme changes in environmental conditions. 

Most organisms on Earth are diploids, which means their DNA contains a single pair of chromosomes. However, this is not the case for every organism. Some organisms, such as males of certain species of bees, have DNA that consists of single unpaired chromosomes, and these organisms are known as monoploids. Some organisms, known as polyploids, have two or more pairs of chromosomes.

Diploid plants can rapidly evolve into polyploids by doubling the number of chromosomes they have — a process known as whole-genome duplication, or polyploidy. The researchers suspect this is what happened to P. australis. 

There are two ways that a diploid plant can become a polyploid. It can happen when two separate but closely related species reproduce. Rather than combining parental DNA like a standard hybrid does, polyploid offspring get an entire copy of each parent's DNA. This is known as allopolyploidy. Polyploids can also emerge when two individuals from separate populations of the same species reproduce, and the offspring gets both complete sets of DNA. This is known as autopolyploidy. In both cases, the process is completely random and offspring becomes a brand new species because it is unable to reproduce with other individuals from its parents' species. 

In the case of P. australis, the researchers determined that the self-cloning seagrass likely emerged via autopolyploidy from a diploid ancestor that has likely since gone extinct. 

Polyploid plants are sometimes regarded as "evolutionary dead ends" because many are sterile, meaning they cannot reproduce sexually, Sinclair said. This limits the plants' ability to mutate, which is a key part of the theory of evolution. However, becoming a polyploid may can act as a last chance for plants that are facing extinction due to extreme environmental changes. 

"Combining two different genomes has essentially doubled the genetic diversity in the plant, likely increasing its ability to tolerate a wider range of environmental conditions," Sinclair said.

Changing conditions 

Until around 8,500 years ago, Shark Bay was actually above sea level and part of continental Australia. But rising sea levels caused by the end of the Last Glacial Period, the most recent ice age that ended around 12,000 years ago, submerged that part of the continent. The newly created marine habitat was inundated with new species, such as seagrasses. 

However, Shark Bay would have been a very unstable environment at the time because of its shallow water. Today, the average depth of Shark Bay is around 30 feet (9 meters) across the entire 8,880 square mile (23,000 square km) area, but it would have been even shallower around 4,500 years ago when P. australis emerged. Shallow oceans are more vulnerable to extreme shifts in temperature and salinity because there is less water to distribute and circulate heat and minerals. Their ecosystems are also more prone to disturbance and damage from tropical storms than deep-sea environments are.

In the study, the researchers suggested that if P. australis became polyploid before some type of extreme environmental upheaval during this more turbulent period, that gave P. australis an advantage over its diploid predecessors, which were unable to survive whatever change occurred.

Shark Bay continues to experience extreme conditions today to some degree. Annual temperatures can range between 63 and 86 degrees Fahrenheit (17 and 30 degrees Celsius), and the water is very salty. The bay's shallowness also means it is at risk from increasingly powerful heat waves caused by climate change, and is potentially susceptible to damage from cyclones. However, the environment is more stable than it was when P. australis first emerged. 

P. australis has likely continued to thrive in the area for millennia thanks to its resilience to environmental changes; other local seagrass species that continue to reproduce sexually, which is energetically expensive and requires lots of available space for new plants to grow, may be less resilient, Sinclair said. Without having to compete for space or divert energy to reproduction, P. australis has been free to clone itself at a steady pace and dominate the local ecosystem, she added.

Originally published on Live Science.

In 1996, Dolly the sheep made headlines around the world after becoming the first mammal to be successfully cloned from an adult cell. Many commentators thought this would catalyze a golden age of cloning, with numerous voices speculating that the first human clone must surely be just a few years away. 

Some people suggested that human clones could play a role in eradicating genetic diseases, while others considered that the cloning process could, eventually, eliminate birth defects (despite research by a group of French scientists in 1999 finding that cloning may actually increase the risk of birth defects). 

There have been various claims — all unfounded, it is important to add — of successful human cloning progams since the success of Dolly. In 2002, Brigitte Boisselier, a French chemist and devout supporter of Raëlism — a UFO religion based on the idea that aliens created humanity — claimed that she and a team of scientists had successfully delivered the first cloned human, whom she named Eve.

However, Boisselier was unwilling — or indeed unable — to provide any evidence, and so it is widely believed to be a hoax. 

So why, almost 30 years on from Dolly, haven't humans been cloned yet? Is it primarily for ethical reasons, are there technological barriers, or is it simply not worth doing?

Related: What are the alternatives to animal testing?

"Cloning" is a broad term, given it can be used to describe a range of processes and approaches, but the aim is always to produce "genetically identical copies of a biological entity," according to the National Human Genome Research Institute (NHGRI).

Any attempted human cloning would most likely utilize "reproductive cloning" techniques — an approach in which a "mature somatic cell," most probably a skin cell, would be used, according to NHGRI. The DNA extracted from this cell would be placed into the egg cell of a donor that has "had its own DNA-containing nucleus removed."

The egg would then begin to develop in a test tube before being "implanted into the womb of an adult female," according to NHGRI.

However, while scientists have cloned many mammals, including cattle, goats, rabbits and cats, humans have not made the list.

"I think there is no good reason to make [human] clones," Hank Greely, a professor of law and genetics at Stanford University who specializes in ethical, legal and social issues arising from advances in the biosciences, told Live Science in an email.

"Human cloning is a particularly dramatic action, and was one of the topics that helped launch American bioethics," Greely added.

The ethical concerns around human cloning are many and varied. According to Britannica, the potential issues encompass "psychological, social and physiological risks." These include the idea that cloning could lead to a "very high likelihood" of loss of life, as well as concerns around cloning being used by supporters of eugenics. Furthermore, according to Britannica, cloning could be deemed to violate "principles of human dignity, freedom and equality." 

In addition, the cloning of mammals has historically resulted in extremely high rates of death and developmental abnormalities in the clones, Live Science previously reported.

Another core issue with human cloning is that, rather than creating a carbon copy of the original person, it would produce an individual with their own thoughts and opinions.

"We've all known clones — identical twins are clones of each other — and thus we all know that clones aren't the same person," Greely explained.

A human clone, Greely continued, would only have the same genetic makeup as someone else — they would not share other things such as personality, morals or sense of humor: these would be unique to both parties.

People are, as we well know, far more than simply a product of their DNA. While it is possible to reproduce genetic material, it is not possible to exactly replicate living environments, create an identical upbringing, or have two people encounter the same life experiences.

Would cloning humans have any benefits?

So, if scientists were to clone a human, would there be any benefits, scientific or otherwise?

"There are none that we should be willing to consider," Greely said, emphasizing that the ethical concerns would be impossible to overlook.

However, if moral considerations were removed entirely from the equation, then "one theoretical benefit would be to create genetically identical humans for research purposes," Greely said, though he was keen to reaffirm his view that this should be thought of as "an ethical non-starter."

Greely also stated that, regardless of his own personal opinion, some of the potential benefits associated with cloning humans have, to a certain degree, been made redundant by other scientific developments.

"The idea of using cloned embryos for purposes other than making babies, for example producing human embryonic stem cells identical to a donor's cells, was widely discussed in the early 2000s," he said, but this line of research became irrelevant — and has subsequently not been expanded upon — post-2006, the year so-called induced pluripotent stem cells (iPSCs) were discovered. These are "adult" cells that have been reprogrammed to resemble cells in early development.

Shinya Yamanaka, a Japanese stem cell researcher and 2012 Nobel Prize winner, made the discovery when he "worked out how to return adult mouse cells to an embryonic-like state using just four genetic factors," according to an article in Nature. The following year, Yamanaka, alongside renowned American biologist James Thompson, managed to do the same with human cells.

When iPSCs are "reprogrammed back into an embryonic-like pluripotent state," they enable the "development of an unlimited source of any type of human cell needed for therapeutic purposes," according to the Center of Regenerative Medicine and Stem Cell Research at the University of California, Los Angeles.  

Therefore, instead of using embryos, "we can effectively do the same thing with skin cells," Greely said.

This development in iPSC technology essentially rendered the concept of using cloned embryos both unnecessary and scientifically inferior.  

Related: What is the most genetically diverse species?

Nowadays, iPSCs can be used for research in disease modeling, medicinal drug discovery and regenerative medicine, according to a 2015 paper published in the journal Frontiers in Cell and Developmental Biology.

Additionally, Greely also suggested that human cloning may simply no longer be a "sexy" area of scientific study, which could also explain why it has seen very little development in recent years.

He pointed out that human germline genome editing is now a more interesting topic in the public's mind, with many curious about the concept of creating "super babies," for example. Germline editing, or germline engineering, is a process, or series of processes, that create permanent changes to an individual’s genome. These alterations, when introduced effectively, become heritable, meaning they will be handed down from parent to child.

Such editing is controversial and yet to be fully understood. In 2018, the Council of Europe Committee on Bioethics, which represents 47 European states, released a statement saying that "ethics and human rights must guide any use of genome editing technologies in human beings," adding that "the application of genome editing technologies to human embryos raises many ethical, social and safety issues, particularly from any modification of the human genome which could be passed on to future generations."

However, the council also noted that there is "strong support" for using such engineering and editing technologies to better understand "the causes of diseases and their future treatment," noting that they offer "considerable potential for research in this field and to improve human health."

George Church, a geneticist and molecular engineer at Harvard University, supports Greely's assertion that germline editing is likely to garner more scientific interest in the future, especially when compared with "conventional" cloning.

"Cloning-based germline editing is typically more precise, can involve more genes, and has more efficient delivery to all cells than somatic genome editing," he told Live Science.

However, Church was keen to urge caution, and admitted that such editing has not yet been mastered.

"Potential drawbacks to address include safety, efficacy and equitable access for all," he concluded.

Originally published on Live Science.

In 1996, Dolly the sheep made headlines around the world after becoming the first mammal to be successfully cloned from an adult cell. Many commentators thought this would catalyze a golden age of cloning, with numerous voices speculating that the first human clone must surely be just a few years away. 

Some people suggested that human clones could play a role in eradicating genetic diseases, while others considered that the cloning process could, eventually, eliminate birth defects (despite research by a group of French scientists in 1999 finding that cloning may actually increase the risk of birth defects). 

There have been various claims — all unfounded, it is important to add — of successful human cloning progams since the success of Dolly. In 2002, Brigitte Boisselier, a French chemist and devout supporter of Raëlism — a UFO religion based on the idea that aliens created humanity — claimed that she and a team of scientists had successfully delivered the first cloned human, whom she named Eve.

However, Boisselier was unwilling — or indeed unable — to provide any evidence, and so it is widely believed to be a hoax. 

So why, almost 30 years on from Dolly, haven't humans been cloned yet? Is it primarily for ethical reasons, are there technological barriers, or is it simply not worth doing?

Related: What are the alternatives to animal testing?

"Cloning" is a broad term, given it can be used to describe a range of processes and approaches, but the aim is always to produce "genetically identical copies of a biological entity," according to the National Human Genome Research Institute (NHGRI).

Any attempted human cloning would most likely utilize "reproductive cloning" techniques — an approach in which a "mature somatic cell," most probably a skin cell, would be used, according to NHGRI. The DNA extracted from this cell would be placed into the egg cell of a donor that has "had its own DNA-containing nucleus removed."

The egg would then begin to develop in a test tube before being "implanted into the womb of an adult female," according to NHGRI.

However, while scientists have cloned many mammals, including cattle, goats, rabbits and cats, humans have not made the list.

"I think there is no good reason to make [human] clones," Hank Greely, a professor of law and genetics at Stanford University who specializes in ethical, legal and social issues arising from advances in the biosciences, told Live Science in an email.

"Human cloning is a particularly dramatic action, and was one of the topics that helped launch American bioethics," Greely added.

The ethical concerns around human cloning are many and varied. According to Britannica, the potential issues encompass "psychological, social and physiological risks." These include the idea that cloning could lead to a "very high likelihood" of loss of life, as well as concerns around cloning being used by supporters of eugenics. Furthermore, according to Britannica, cloning could be deemed to violate "principles of human dignity, freedom and equality." 

In addition, the cloning of mammals has historically resulted in extremely high rates of death and developmental abnormalities in the clones, Live Science previously reported.

Another core issue with human cloning is that, rather than creating a carbon copy of the original person, it would produce an individual with their own thoughts and opinions. "We've all known clones — identical twins are clones of each other — and thus we all know that clones aren't the same person," Greely explained.

A human clone, Greely continued, would only have the same genetic makeup as someone else — they would not share other things such as personality, morals or sense of humor: these would be unique to both parties.

People are, as we well know, far more than simply a product of their DNA. While it is possible to reproduce genetic material, it is not possible to exactly replicate living environments, create an identical upbringing, or have two people encounter the same life experiences.

Would cloning humans have any benefits?

So, if scientists were to clone a human, would there be any benefits, scientific or otherwise?

"There are none that we should be willing to consider," Greely said, emphasizing that the ethical concerns would be impossible to overlook.

However, if moral considerations were removed entirely from the equation, then "one theoretical benefit would be to create genetically identical humans for research purposes," Greely said, though he was keen to reaffirm his view that this should be thought of as "an ethical non-starter."

Greely also stated that, regardless of his own personal opinion, some of the potential benefits associated with cloning humans have, to a certain degree, been made redundant by other scientific developments.

"The idea of using cloned embryos for purposes other than making babies, for example producing human embryonic stem cells identical to a donor's cells, was widely discussed in the early 2000s," he said, but this line of research became irrelevant — and has subsequently not been expanded upon — post-2006, the year so-called induced pluripotent stem cells (iPSCs) were discovered. These are "adult" cells that have been reprogrammed to resemble cells in early development.

Shinya Yamanaka, a Japanese stem cell researcher and 2012 Nobel Prize winner, made the discovery when he "worked out how to return adult mouse cells to an embryonic-like state using just four genetic factors," according to an article in Nature. The following year, Yamanaka, alongside renowned American biologist James Thompson, managed to do the same with human cells.

When iPSCs are "reprogrammed back into an embryonic-like pluripotent state," they enable the "development of an unlimited source of any type of human cell needed for therapeutic purposes," according to the Center of Regenerative Medicine and Stem Cell Research at the University of California, Los Angeles.  

Therefore, instead of using embryos, "we can effectively do the same thing with skin cells," Greely said.

This development in iPSC technology essentially rendered the concept of using cloned embryos both unnecessary and scientifically inferior.  

Related: What is the most genetically diverse species?

Nowadays, iPSCs can be used for research in disease modeling, medicinal drug discovery and regenerative medicine, according to a 2015 paper published in the journal Frontiers in Cell and Developmental Biology.

Additionally, Greely also suggested that human cloning may simply no longer be a "sexy" area of scientific study, which could also explain why it has seen very little development in recent years.

He pointed out that human germline genome editing is now a more interesting topic in the public's mind, with many curious about the concept of creating "super babies," for example. Germline editing, or germline engineering, is a process, or series of processes, that create permanent changes to an individual’s genome. These alterations, when introduced effectively, become heritable, meaning they will be handed down from parent to child.

Such editing is controversial and yet to be fully understood. In 2018, the Council of Europe Committee on Bioethics, which represents 47 European states, released a statement saying that "ethics and human rights must guide any use of genome editing technologies in human beings," adding that "the application of genome editing technologies to human embryos raises many ethical, social and safety issues, particularly from any modification of the human genome which could be passed on to future generations."

However, the council also noted that there is "strong support" for using such engineering and editing technologies to better understand "the causes of diseases and their future treatment," noting that they offer "considerable potential for research in this field and to improve human health."

George Church, a geneticist and molecular engineer at Harvard University, supports Greely's assertion that germline editing is likely to garner more scientific interest in the future, especially when compared with "conventional" cloning.

"Cloning-based germline editing is typically more precise, can involve more genes, and has more efficient delivery to all cells than somatic genome editing," he told Live Science.

However, Church was keen to urge caution, and admitted that such editing has not yet been mastered.

"Potential drawbacks to address include safety, efficacy and equitable access for all," he concluded.

Originally published on Live Science.

The idea of human cloning was science fiction when it was first imagined. But in the last few decades, technological and scientific advances have made this a real possibility. Although the ethics of cloning a human are questionable, the technology has led to some promising reproductive and health therapies. 

The most basic definition of cloning is the creation of an exact genetic copy of an organism, tissue, cell or gene, according to the U.S. National Library of Medicine. The how and why of cloning really depends on what is being cloned. There are three main types of cloning: Gene cloning, reproductive cloning and therapeutic cloning. 

Related: How stem cell cloning works (infographic)

The most commonly applied type of cloning is gene cloning. At its most basic, gene cloning is a biochemical reaction that takes place in every single cell in every organism. It's the creation of a copy of genetic material from an existing strand of genetic material. This natural reaction can be recreated in the lab and is an essential tool for many aspects of biological research.

The most commonly discussed and debated type of cloning is reproductive cloning. This type of cloning creates genetic duplicates of whole organisms from the genetic material of an already-existing organism. A cloned organism is very similar to being an identical twin to the parent organism, just born later. 

And perhaps the most medically applicable type of cloning for humans is therapeutic cloning, which creates cloned embryonic stem cells of a patient to create genetically identical cells that can treat a medical condition. "Therapeutic cloning refers to the use of embryonic stem cells that in our lab we derive from somatic cells from a patient's skin," Shoukhrat Mitalipov, an embryologist at Oregon Health & Science University in Portland, told LiveScience in an email. "In our research lab … we can develop [these cells] into different kinds of cells in the body such as neurons or cardiovascular cells."

Is cloning real?

Yes, cloning is real, but it may not look like it does in science fiction stories. 

Some types of cloning occur in nature regularly. For example, bacteria can reproduce asexually, essentially cloning themselves all the time. Similarly, parthenogenesis is a unique biological phenomenon that results in the spontaneous creation of natural clones — it happens in some species of sharks, amphibians, lizards and snakes. In humans, every cell in the body is a clone of the first embryo cell created when the father's sperm fertilized the mother's egg, and identical twins are natural clones. 

Related: Rare 'virgin birth' of shark in Italian aquarium could be first of its kind 

Cloning is also very real in the biology lab — researchers worldwide use gene cloning in many ways. For example, it can create large amounts of proteins for medications like insulin or be used to detect the presence of specific strands of DNA, like in the COVID-19 PCR test. 

It has been more than a quarter of a century since researchers first cloned animals from adult cells. The most well-known animal clone is Dolly the sheep, created in 1996 at the University of Edinburgh. While not the first cloned mammal, Dolly was the first created from an adult cell, rather than an embryonic or fetal cell. 

To create Dolly, researchers needed to clone 277 embryos, 29 of those were healthy enough to implant, but only one survived until birth. In those early years, cloned embryos faced many failures, and the animals born alive sometimes died prematurely. According to the National Human Genome Research Institute, sheep and other cloned mammals have had various organ defects, including the heart, brain and liver. Other reports suggest issues with premature aging, increased birth size and immune system issues.

Related: 20 years after Dolly the sheep, what have we learned about cloning? 

The success of Dolly brought a flurry of media attention to cloning — both its potential benefits and the world's fears. As a result, many countries rushed to ban cloning of all kinds. 

Nevertheless, in the decades since Dolly, animal cloning has come a long way. Some services will clone pets, as Barbra Streisand had done with her pet, Smithsonian Magazine reported. Some companies will even clone an entire polo team. Polo team La Dolfina, and world-class player Adolfo Cambiaso, have for several years used cloned horses, according to a 2016 article in Science magazine. 

Related: Cloning mammoths is still a dream. 

The work to clone other animals has been a slow, uphill battle but over the past few decades, researchers have been working their way toward cloning humans.

In 2007, Mitalipov’s research team cloned the first primate embryos — rhesus macaque — and used them to create embryonic stem cells, publishing the process in the journal Nature. But it took until 2018 for these technologies to result in a living cloned monkey, achieved by a team of Chinese scientists and described in their paper published in the journal Cell, Live Science previously reported. The researchers made about 80 cloned embryos, ending up with six pregnancies and just two live births.

Six years after cloning the monkeys, Mitalipov’s team created embryonic stem cells from cloned human embryos, research he published in 2013 in the journal Cell. At this point, many of the technologies needed to create human clones exist, but there are still many roadblocks and ethical arguments against using them to clone a human. 

How does cloning work?

As cells grow and divide, they naturally create clones using cellular division, a process called mitosis. The cells use proteins and enzymes coded in their genes to copy their genetic material. As researchers developed an understanding of how cells reproduce their genes, scientists began recreating these reactions in the lab. Now, cloning genes in the lab is as easy as mixing a drink — combining the proteins that cells use to copy their DNA and adding a gene to copy.

"Cloning DNA or cells is simple; it's the nature of DNA to replicate itself," Mitalipov said. "But when we say cloning of an entire organism, that's much more complex."

Most multicellular organisms replicate themselves through sexual reproduction. This process takes half of the genetic code from one organism (an egg) and half from another (a sperm). It remixes them, creating a single cell that can turn into a whole new being — an embryo that might grow into a new organism if it implants in the right uterus. 

But the goal of cloning is to create an embryo without remixing the genome. To do this, the researchers first start with a body cell, called a somatic cell. Somatic cells make up the majority of the body — the skin, internal organs, brain cells. A somatic cell's genome has been "set" like jello into a specific shape. 

Differences in the structure of somatic cell DNA dictate what genes the cell can express, according to the U.S. National Libraries of Medicine. The differences in gene expression, dictated by chemical changes called epigenetic modifications, determine how the cell looks, how it acts, and what it does in the body. And that process is limiting — that cell then can't do anything else in the body. It will just age and die, and be broken down into parts to be reused.

Embryonic cells, or stem cells, on the other hand, have the potential to become any type of cell in the body because the genes they can express aren't locked in like they are in somatic cells. Researchers use both types of cells to create clones. The process originally used to create Dolly the sheep is called somatic cell nuclear transfer, as described in a 2015 review in the journal Philosophical Transactions of the Royal Society B. In this process, scientists remove the nucleus, or genetic hub, of a somatic cell and insert it into an egg cell that has had its genome removed. 

If successful, this process will reset the somatic genome's epigenetics, and result in a cloned embryo with an exact copy of the genome of the somatic cell without the epigenetic modifications. It sounds straightforward, but the process is incredibly finicky — to be successful the egg needs exactly the right conditions, and these conditions differ with every species. So, when scientists attempt to clone a new animal, they're faced with making many adjustments to the general process, Mitalipov said. 

"You'd have to resolve lots of mysteries and there's no standard protocol to do it," Mitalipov said. "Everything needs to be tweaked a little bit depending on the difference in species."

These might have to do with the chemical environment (including the presence of caffeine in the petri dish for human embryos) that the experiment is performed in, the application of a jolt of electricity, the timing of the steps and even how forcefully the embryo is touched while removing and inserting the somatic cell nucleus.

In his 2013 Nature paper, Mitalipov and his colleagues showed that they had found the conditions to successfully clone a human somatic cell into an embryo, which was then used to create a human embryonic stem cell line. 

Can humans be cloned?

Following the Mitalipov team's breakthrough in 2013, and the first cloned primates in 2018, the world has been waiting to see if anyone would actually clone a human. But this hasn't happened — yet. 

But is it possible? The short answer is likely yes. The technology exists and there's nothing significantly different about how human genes or genetics work compared with those of other animals that have been cloned. But, based on the difficulties experienced in developing cloned animal embryos into living, full-term births, there's no saying what types of conditions or diseases a human clone might have if one was born. We also know that it would likely require creating many many embryos to get one live birth — a very ethically murky proposition.

Related: Artist's 'cloning agency' replicates Jesus, Lady Gaga

Additionally, humans (and other animals) are more than their DNA. The environment human bodies and brains are exposed to in the womb, during development and extending through childhood and young adulthood, plays a big part in creating who a person is. And just as epigenetic modifications alter how genes are expressed to create specialized somatic cells, they also reflect the things cells and bodies have gone through — adding another major layer of complication into the question.

Ethical considerations of human cloning

families, many others believe this kind of research is ethically problematic.

The creation and destruction of human embryos is a sticking point for many major religions, and others worry about the potential diseases and conditions that this process might inflict on a cloned baby. 

Related: Human cloning? Stem cell advance reignites ethics debate

For these reasons and more, many countries and U.S. states have put bans on human cloning experiments. In the U.S., there are no federal laws against cloning humans, but multiple states have laws prohibiting cloning for any purpose. Multiple others prohibit funding of human cloning. According to intellectual property attorneys Knobbe Martens, 10 states allow the creation of human cloned embryos but prevent them from being implanted — researchers can destroy them to create embryonic stem cell lines. 

The use of three-parent IVF is illegal due to a 2015 amendment introduced by Rep. Robert Aderholt, a Republican from Alabama, to the 2016 appropriations bill. The amendment forbade clinical trials of heritable genetic modifications. However, patients and scientists are pushing to change that, according to STAT News.

More than 30 countries ban human cloning experiments, according to a 2007 review published by Rice University. In 15 countries, there are bans on human reproductive cloning but not on the creation of cloned embryonic stem cells. Other countries do not have any specific legislation banning human cloning.

How cloning technology is used

While polo ponies are no doubt important to some, there are several other ways that technologies developed through these cloning experiments may be important in the future, Mitalipov said. 

Mitalipov's work on somatic cell nuclear transfer in humans has led directly to the development of reproductive technologies that allow women with mitochondrial diseases (which these women pass down to offspring through their eggs) and infertility issues to have healthy children that are genetically related to them. Previously, women with mitochondrial diseases had no recourse other than to pass their condition on or not have biological children. 

Now, technology developed by Mitalipov's lab is used to strip donor eggs of their DNA and move the nucleus from the mother's egg, resulting in a healthy embryo that is genetically related to the mother, according to a 2014 review in the journal Fertility and Sterility. Multiple "three-parent babies" have been born using these methods at clinics in the Ukraine and Greece, according to STAT News. 

Related: Prenatal genetic screening tests: Benefits & risks

The ability to create cloned embryonic stem cells using somatic nuclear transfer is also promising for developing therapies that a patient's immune system wouldn't reject. These clonal stem cell therapies could create new organs or cells for people that could replace damaged ones.

"You can theoretically use those cells to treat a patient with a neurodegenerative disease or a cardiovascular disease," Mitalipov said. These cells "could, in theory, lead to the development of stem cell therapies treating neurodegenerative diseases like Parkinson's, cardiac disease and spinal cord injuries."

The cloned stem cells can be created now, but there are roadblocks on the research and clinical end to developing these therapies. 

"Unfortunately, no therapies have been developed yet," Mitalipov said. "We can grow neurons in a petri dish, but how do you integrate neurons into the brain or other types of cells into relevant organs like the heart? It's going to be very difficult."

In the future, Mitalipov hopes that some of the technologies he's working on now can help create genetically related babies for same-sex couples or infertile couples. For example, his lab is currently figuring out how to remove half of the DNA from a cloned embryonic cell to create an egg cell. 

If researchers create a cloned egg cell from the somatic cells of a man or infertile female, it could then be fertilized with the sperm from another man, creating an embryo. Using the cloning technology this way would give same-sex or infertile couples a way to have genetically related babies. 

Additional resources

• Read expert commentary on the potential global regulation of human cloning. 
• Here are some helpful FAQs about cloning from the National Human Genome Research Institute. 
• Read this opinion piece on why humans haven't tried to clone themselves yet, published in STAT News. 

Welcome to Jurassic Park. As we open the gates to this zoo of previously extinct creatures, how would you expect the dinosaurs behind them to look? For those who have read or watched "Jurassic Park," the image of a dinosaur may have already been planted in your mind. Your perception might be plagued by the gruesome scenes of park rangers becoming easy meals, or the film's iconic theme tune might resonate in your head as you envision herds of long-necked beasts parading across the land. With great species diversity, the thrill of this dinosaur park cannot be denied. But can a Jurassic Park really happen? 

When Michael Crichton first conceived the "Jurassic Park" story in the late 1980s, one of the last things he wrote was perhaps the most significant. How would the scientists in the story obtain the DNA needed to create a theme park of dinosaurs? This would be the key to the entire plot, giving the story a feeling of scientific realism. Eventually, Crichton was inspired by a scientific paper he read, according to an interview with paleobiologist George Poinar, Jr. in an interview with Science Friday. 

The paper, published in the journal Science in 1982, referenced a fly that had been found preserved inside hardened tree resin. Somehow, at the end of its life, the fly had ended up submerged in this resin time capsule. This was not just the stroke of genius that led to the creation of this fictional land, but a real-life discovery. Together the story of "Jurassic Park" and the science at the center of the tale would inspire the next generation of paleontologists, opening the world's imagination to dinosaurs. 

What might fascinate people most about dinosaurs is the multitude of unanswered questions, with only hints at their dominance before our time. What did dinosaurs really look like, and how did their unique appendages assist them as they scoured the land in diverse groups? 

As humans have never lived alongside dinosaurs, nobody holds the answers to some of the questions. We continue to learn more about dinosaurs as scientists uncover and research more and more fossils. Scientists have now discovered more than 700 dinosaur species worldwide.

Scientists are now working on reversing extinction by bringing animals that vanished from Earth long ago back into our lives. By editing the genetic code in the DNA of extinct animals' closest living relatives, scientists can slowly build backwards and manipulate a model of the species' DNA. One of the most high-profile cases involves the woolly mammoth, which died out around 4,000 years ago. Mammoth DNA is preserved in the frozen soil of Siberia, so scientists are working on a project to combine these fragments of genetic code with that of living elephants. There might be thousands of years separating these species — and over 60 million years for dinosaurs — but if scientists are successful in producing these extinct species, it could be a stepping stone toward the beginning of a true Jurassic Park.

Have we found dinosaur DNA?

The biggest hurdle to overcome before we can create a dinosaur park is how to source the main ingredient. Without access to dinosaur DNA, researchers can't clone true dinosaurs. New fossils are being uncovered from the ground every day. However, while this can provide important evidence of a species' form, its organic material has long since disappeared. Instead of bone, dinosaur fossils consist of rock and sediment that has filled the bone's place. While these clues can tell us about a specimen's shape and size, the time it was alive and any unique features the animal had, they are unable to give us the crucial genetic information. 

In 2020, researchers from the U.S. and China discovered cartilage that they believe contains dinosaur DNA, according to a study published in the journal National Service Review. Many paleontologists are skeptical about this claim, as it is widely believed to be impossible for the protein in these molecules to survive for millions of years, according to an article published in The Conversation. The cartilage, from the Hypacrosaurus species of the Cretaceous Period, is over 70 million years old but has been calcified and fossilized, which may have protected the inside of the cells.

Could we create a dinosaur?

So, will it ever be possible to bring a dinosaur back from extinction? It's something that scientists are trying to work out, although the process would be quite different to how it's portrayed in the movies. "We think we have found signals for DNA and that there might be tiny bits left, but not enough to use to make a dinosaur. We can get collagen and some dinosaur proteins, but not all the material we need," paleontologist Jack Horner told How It Works magazine. "If we had the DNA, it would be ridiculous to put it in an ostrich egg. The thing to do would be to grow it in a test tube, because we have no idea how big the embryos of all dinosaurs are. Some dinosaur eggs are the size of ostrich eggs, but for a Tyrannosaur, we think they are a lot longer and they're bigger. It's like thinking about putting a human embryo inside a squirrel."

Horner is the real paleontologist who inspired the character of Alan Grant in "Jurassic Park." Since finding his first dinosaur bone at the age of 8, Horner has dug up the first dinosaur embryos, the first dinosaur eggs in the Western world, and discovered and named the dinosaur species Maiasaura. He was also the palaeontology consultant for the "Jurassic Park" films. And while he deems the cloning process pure fiction, it hasn't stopped Horner from trying to bring back the dinosaurs.

"I actually have a laboratory where we are attempting to figure out how to make a dinosaur," he told How It Works, a sister site of Live Science. "It's called the dino-chicken project, and it's mostly based on genetic engineering. The idea is to use atavistic genes. They are basically ancestral genes, meaning that ancestral animals programmed certain features. For instance, occasionally children are born with extra vertebrae and form a low tail, which the doctor just picks off when the child is born. And every once in a while snakes are born with little appendages."

Horner's plan is to take advantage of these atavistic genes. "I was hoping that some of the features of a dinosaur were atavistic in a bird. All bird species are related to one another, with one common ancestor — dinosaurs — so any bird should work. Chickens are the easiest thing to get eggs from, so I built a laboratory, hired some geneticists and developmental biologists and started seeing if we could find some of these potential atavistic genes," he said. 

"We've been working on the tail, mostly, because that seems to be the hardest part," he added. "We discovered that the reduction of the tail from long-tail dinosaur to a short-tail bird is not an atavistic gene. We are trying to figure out how the tail actually works and reverse the process that formed the short tail." 

So, are we any closer to making a dinosaur? "Other laboratories have looked at the face, teeth, arms and hands. I think we can do pretty much all the rest of the body. We have the potential of making an animal that has a dinosaur-like head, probably with teeth in it, and we certainly have the capability of reversing the wings to make arms and hands. We know we can do that, but right now we're just trying to fix the tail," Horner said.

Living with dinosaurs

If humans did succeed in bringing dinosaurs back from extinction, how would we coexist? If dinosaurs hadn't gone extinct, humans are unlikely to have been able to evolve. During the 150 million years that dinosaurs existed, mammals lived alongside them, but these animals were nocturnal and lived in burrows. This suggests that this was the only way for mammals to thrive alongside dinosaurs, emerging mainly at night to hunt. Because our lives are completely separate to that of dinosaurs, there's no way of knowing what would happen if dinosaurs were to live on the same land as us. 

By observing human behavior with today's large predators, it seems unlikely that the two species would live naturally together. Humans take up so much space on the planet that introducing predators like dinosaurs outside of captivity would likely result in a battle for land.

Horner, however, has a different view. “People always say, 'Where are you going to put these dinosaurs when you make them?' and I always say that many thousands of years ago we started with wolves, and now we have chihuahuas,” he said. “Dogs are basically wolves, and we don't really have to contain them. I wouldn't expect dino-chickens to be the same as the dinosaurs in “Jurassic Park.” They're going to be domestic animals that we don't have to worry about. If you were cloning a real Tyrannosaur, you would have to worry about containing them. Dogs and cats were wild, but now we don't have to contain them — not to the point of making a park anyway.”

Even if the problem of recreating a dinosaur was overcome, could we keep them alive? Some studies of air trapped in amber show that its composition during the Cretaceous Period may have been 35% oxygen, as opposed to 21% today, according to New Scientist. However, during the dinosaurs' extended time on the planet, this number is believed to have varied substantially. Some species would therefore be better suited to our air than others. 

It's also been determined that when dinosaurs roamed the Earth, the global temperature would have been much higher than it is today, according to the National Oceanic and Atmospheric Administration. An island in a tropical region of the globe would be the best bet to provide temperatures that many dinosaurs would be comfortable living in.

And as far as containing them is concerned, the park would need to look quite different to how it appears in the film. “If you really, seriously want to build a Jurassic Park and are not just making a movie, you want walls around the dinosaurs to keep them in.” Horner told How It Works. “Reinforced concrete is going to work a lot better than electric fences, because electricity can go out. Electric fences were not a very good idea.”

Researchers have successfully cloned a highly endangered ferret species using cells that were frozen more than three decades ago, according to news reports.

The adorable clone, named Elizabeth Ann, is a species of black-footed ferret, one of the most endangered mammals in North America, according to the World Wildlife Fund for Nature. Born on Dec. 10, 2020, Elizabeth Ann was created using cells from "Willa," a wild black-footed ferret who died and had her cells cryopreserved in 1988, according to a statement from the U.S. Fish and Wildlife Service (USFWS), which was involved in the cloning.

The feat marks the first time an endangered species in the U.S. has been cloned, the statement said. Researchers hope Elizabeth Ann will help bring genetic diversity to the black-footed ferret population, which today is descended from just seven individual ferrets, making all living members of the species essentially half-siblings, according to The New York Times. 

"It was a commitment to seeing this species survive that has led to the successful birth of Elizabeth Ann," Ryan Phelan, executive director of Revive & Restore, a conservation organization that was involved with the cloning, said in the statement. "To see her now thriving ushers in a new era for her species and for conservation-dependent species everywhere. She is a win for biodiversity and for genetic rescue."

Related: 8 mammals that have been cloned since dolly the sheep

Black-footed ferrets were once thought to be extinct, but scientists found a small population in 1981, which allowed conservationists to start captive breeding programs for the species. About 250 to 350 of the ferrets live in captivity, and 300 more live in reintroduction sites in the wild, according to Revive & Restore. But the limited genetic diversity of the species has challenged its recovery, making the creatures prone to health disorders and certain infections, the Times reported.

Since Willa was not one of the "seven founders" of the population, her genes — which are now possessed by Elizabeth Ann — could bring much-needed variation to the population's genetics.

The project to clone a black-footed ferret began in 2013, and was a result of a partnership between USFWS, Revive & Restore, the company ViaGen Pets & Equine, San Diego Zoo Global, and the Association of Zoos and Aquariums.

Several other endangered animals have been cloned in other parts of the world, including gaur, or wild cattle, in 2001, bucardo, or wild goats, in 2009, and wild coyotes in 2012, according to Scientific American.

Originally published on Live Science.  

A 42,000-year-old foal discovered frozen in Siberian permafrost contained a surprise: the oldest liquid blood on record.

This is the second time that a defrosted Ice Age animal has turned out to contain liquid blood, said Semyon Grigoriev, the head of the Mammoth Museum at North-Eastern Federal University in Yakutsk. In 2018, Grigoriev and his colleagues extracted liquid blood from a 32,200-year-old mammoth carcass. That makes the foal's blood the oldest ever found by 10,000 years.

Grigoriev and his colleagues are set on cloning a mammoth and other Pleistocene fauna, and they're already trying to clone the foal, a member of an extinct species called the Lena horse. It's a long shot, though, Grigoriev wrote in an email to Live Science. [Photos: Perfectly Preserved Baby Horse Unearthed in Siberian Permafrost]

"But," he said, "we in Russia say that hope dies last."

Lena horse

The Lena horse (Equus caballus lenensis) foal was found in the Batagaika Crater in eastern Siberia last year. The foal was 1 to 2 weeks old and stood 39 inches (98 centimeters) at the shoulder when it died, drowning in mud. Remarkably, the icy permafrost preserved the foal's skin and hair down to the tiniest detail. There was even well-preserved urine still inside the foal's bladder, Grigoriev said.

The liquid blood was a surprise, he said. Typically, blood coagulates or turns to powder even in well-preserved carcasses, because fluids gradually evaporate over thousands of years, he said. In the mammoth, dubbed "Buttercup" by researchers, the blood was preserved in ice inside the carcass. [Photos: Autopsy of a 40,000-Year-Old Mammoth Named 'Buttercup']

The foal autopsy should reveal a lot about Pleistocene Siberia, Grigoriev said. Not only will researchers study the biochemistry of preserved urine, gut contents and organs, but they will also study samples of the soils and paleo plants found in the layer of permafrost where the foal died.

Cloning the ice age

The blood may not help the researchers reach their goal of reviving an ice age animal. Red blood cells don't have nuclei, so they don't contain DNA, Grigoriev said.

For cloning, the researchers are focusing on muscle cells and internal organs, he said. Even there, finding DNA in good enough condition for cloning is a big challenge. DNA starts to degrade soon after an animal's death, even in excellent preservation conditions such as permafrost, Grigoriev said.

The team has been trying to extract intact cells and quality DNA from the foal for two months, Grigoriev said, without success. The researchers will continue to try both in Yakutsk and at the laboratory of their collaborator Hwang Woo-suk, the CEO of Sooam Biotech in South Korea, he said. Hwang was found guilty of embezzlement and bioethical violations in 2009 after a set of human stem-cell cloning experiments published in the journal Science in 2004 and 2005 turned out to be faked. He then kept a low profile for several years before making headlines for cloning dogs for wealthy clients. According to Vanity Fair, his company has cloned more than 1,000 dogs. He has also been working with Grigoriev and his team on attempts to clone a mammoth.

Grigoriev and his colleagues hope that if they can retrieve viable DNA from a mammoth, they can insert the DNA into an elephant embryo cleared of its genetic information, implant the embryo into an elephant and resurrect the woolly mammoth. A similar process could work for the Lena horse, using modern horses as surrogates. A recent documentary on these efforts, "Genesis 2.0," won a prize for cinematography at the Sundance Film Festival in 2018.

• 6 Extinct Animals That Could Be Brought Back to Life
• How to Bring Back the Woolly Mammoth (Infographic)
• In Photos: Mummified Woolly Mammoth Discovered

Editor's Note: This story has been updated to correct the age of the foal. It was 1 to 2 weeks old, not 2 months, when it died.

Originally published on Live Science.

A handful of 28,0000-year-old woolly mammoth cell parts were recently "woken up" for a short time in a new experiment, but cloning the ice age beasts is still a long way off.

In the experiment, the researchers extracted cells from Yuka, a woolly mammoth mummy (Mammuthus primigenius) whose remains were discovered in the Siberian permafrost in 2011. Then, the scientists recovered the least-damaged nuclei (structures that contain genetic material) from each cell and popped the nuclei into mouse eggs.

At first, this maneuver "activated" the mammoth chromosomes, as several biological reactions that occur before cell division actually happened within the mouse cell. But these reactions soon came to a crashing halt, probably, in part, because the mammoth DNA was severely damaged after spending 28,000 years buried in permafrost, the researchers said. [In Photos: Mummified Woolly Mammoth Discovered]

But why did the researchers put mammoth DNA into mouse eggs? The answer has to do with an egg's ability to replicate DNA and divide into more cells.

"The eggs have all of the living cellular machinery that you might need to do error correction and fix damage that has happened within the nuclei," said Beth Shapiro, a professor of ecology and evolutionary biology at the University of California, Santa Cruz, who was not involved with the study. "[The scientists] basically just stuck [the mammoth nuclei] in there and said, 'All right, cellular machinery, do your thing.'"

And, at first, the cellular machinery did try to fix damaged DNA within the chromosomes and piece together the broken bits, Shapiro said. "But [the egg] can only do so much," she told Live Science. "When the nuclei are badly damaged, then it's just not possible to reconstitute this to what you would need to do to actually bring it back to life."

As a result, none of the mouse-mammoth hybrid cells entered cell division, a step that is necessary to create an embryo and, perhaps one day, clone a mammoth.

"The results presented here clearly show us again the de facto impossibility to clone the mammoth by current NT [nuclear-transfer] technology," the researchers wrote in the study, published online March 11 in the journal Scientific Reports.

Put another way, "it's a pretty clear demonstration that this approach is not going to work to clone a mammoth," Shapiro said. "The cells are too damaged."

As soon as the mammoth died, its DNA began degrading. That's because bacteria from the mammoth's gut and the surrounding environment began chomping down on the dead mammoth's cells. Ultraviolet (UV) radiation from the sun also broke down more of the genetic material, and those processes continued for eons. As a result, DNA fragments in the nucleus that survived to today may be only tens to hundreds of bases long, rather than the millions that are found in the DNA of modern elephants, Shapiro said.

However, the study is still exciting, said Rebekah Rogers, an assistant professor of bioinformatics at the University of North Carolina at Charlotte, who was not involved with the research. For instance, if researchers can insert even small fragments of mammoth DNA into a cell line, that could reveal what that DNA does in a living creature, she said. [Mammoth Resurrection: 11 Hurdles to Bringing Back an Ice Age Beast]

In the study, the researchers added that "our approach paves the way for evaluating the biological activities of nuclei in extinct animal species."

However, Rogers said she would like to see more evidence that the mammoth chromosomes actually made it into the mouse egg. "It's possible that you could have a highly modified mouse chromosome or potentially some other DNA contamination," she said. "They have this extraordinary claim that they put mammoth chromosomes into a mouse [egg]. I would really like to see a lot of evidence for that kind of claim."

Other research groups are also trying to resurrect the mammoth, using different technology. George Church, a geneticist at Harvard University and the Massachusetts Institute of Technology who is heading the Harvard Woolly Mammoth Revival team, is taking one approach. He's using CRISPR — a tool that can edit DNA's bases, or letters — to insert woolly mammoth genes into the DNA of Asian elephants, which are closely related to the extinct animals.

"They're not trying to revive a mammoth genome," Shapiro said. "They are trying to create one by tweaking an elephant genome. In that way, they could have a living cell as an end product."

Bringing back the ice age mammals is controversial, however. Many conservationists argue that resources should be spent on currently threatened or endangered animals rather than beasts that died off long ago.

• Photos: Mammoth Bones Unearthed from Michigan Farm
• Photos: Ice Age Mammoth Unearthed in Idaho
• 6 Extinct Animals That Could Be Brought Back to Life

Originally published on Live Science.

A team of scientists in Siberia is hopeful that a mummified 40,000-year-old baby horse can provide critical genetic material for cloning the extinct ice-age species.

But experts told Live Science that they are skeptical that the scientists will be able to find viable DNA on the body at all, let alone overcome the enormous challenges of cloning a species that's been extinct for millennia.

Revived after millennia?

The preserved foal's body was discovered in August and was excavated from melting permafrost in the Batagaika crater in Yakutia, a region in eastern Russia. Researchers working with the frozen remains recently told The Siberian Times that they are investigating whether the remains will yield living cells that could be used to clone the ancient baby horse. [See Photos of the Perfectly Preserved Ice-Age Foal]

According to The Siberian Times, one of the scientists involved in the analysis of the mummified horse is Woo-Suk Hwang, a stem-cell researcher and cloning pioneer from South Korea. Hwang, a former professor at South Korea's Seoul National University, came under fire in 2006 for falsifying data, and was convicted three years later of bioethical violations and embezzlement, Nature reported in 2009. He now helms Sooam Biotech Research Foundation, a South Korean company that researches and performs animal cloning — primarily dogs, Live Science previously reported.

Scientists from Russia and South Korea — including Hwang — are already collaborating in an attempt to clone a woolly mammoth, and they are now exploring the possibility of extracting living cells from the preserved horse, which could potentially be used to create a clone, Hwang told The Siberian Times.

"If we find only one live cell, we can clone this ancient horse," Hwang said. "We can multiply it and get as many embryos as we need."

An extinct horse could prove easier to clone than a mammoth because a modern horse could serve as the embryo's surrogate, while a cloned mammoth embryo would need to be implanted in a female elephant, Hwang explained. Elephants are in the same family as extinct mammoths, but they are not close relatives — so a cloned "mammoth" would more likely be a genetically engineered elephant-mammoth hybrid, he said.

Nevertheless, cloning an extinct ice-age horse could be a step toward cloning a mammoth, as "it will help us to work out the technology," Hwang told The Siberian Times.

"Astronomical" odds

However, several scientists who were not involved with the analysis of the foal expressed doubts that it would be possible to successfully clone the mummified horse. 

"Many of [the] same challenges will be faced here as with attempts to clone mammoths," Beth Shapiro, a professor of ecology and evolutionary biology at the University of California, Santa Cruz, told Live Science in an email.

Cloning is possible only when the original animal's DNA is intact, and the majority — if not all — of the DNA in ice-age specimens is typically degraded "into tens of millions of pieces," Love Dalén, a professor of evolutionary genetics at the Swedish Museum of Natural History in Stockholm, told Live Science in an email.

If enough DNA from the mummified horse's remains can be recovered, scientists might be able to construct a genome sequence by comparing the DNA of the extinct foal to the genomes of living horses, Shapiro added.

But the chance of finding an undamaged nucleus with an intact genome, or even a frozen cell that could be recovered, "is astronomical," Vincent Lynch, an assistant professor in the Department of Human Genetics at the University of Chicago, told Live Science in an email.

"Scientists rarely say something is impossible, but it is certainly approaching it," Lynch said.

Original article on Live Science.

Toenail fungus is not sexy, and the microbes that cause the infection appear to agree: A new study finds that these fungi have given up on sex — instead, they reproduce by cloning themselves.

That can have consequences for the survival of the species, the researchers said. What's more, it may also open up new avenues for medical treatments.

If the fungus, called Trichophyton rubrum, can't reproduce sexually, it can't diversify at the genetic level, which means it may one day go extinct, the researchers said. And while that would be good news for nearly 2 billion people worldwide who currently have skin and nail fungal infections, it probably won't happen anytime soon. [Tiny & Nasty: Images of Things That Make Us Sick]

"It is commonly thought that if an organism becomes asexual, it is doomed to extinction," Dr. Joseph Heitman, senior author of the study and professor and chair of molecular genetics and microbiology at Duke University School of Medicine, said in a statement. "While that may be true, the time frame we are talking about here is probably hundreds of thousands to millions of years," Heitman said.

Still, the new discovery means that the ability of the fungus to adapt may be limited. So, any new strategies researchers develop to treat it could have more potential for success, compared with treatments that target microbes that reproduce sexually, the researchers said. This is because species that reproduce sexually are more capable of mutating or spreading drug-resistant genes, the researchers said.

T. rubrum is the most common cause of athlete's foot and toenail fungus. Often, people contract this infection by walking barefoot around swimming pools, showers or locker rooms, or by sharing nail clippers. The infection is often difficult to get rid of, and though most treatments — including powders, creams and prescription drugs — can keep the infection at bay, they don't clear it, the researchers said.

Mating studies

In the new study, the researchers examined the genetics and "mating" behavior of T. rubrum. To do so, they collected 135 different samples of the fungi from around the world. Then, they examined the microbes' genome to determine its mating type, or the molecular markers that govern whether two fungal cells can reproduce sexually.

The researchers found that 134 of the 135 samples were from the same mating type, meaning they could not mate together.

Despite this finding, the researchers then tried to coax the microbes into mating with each other — they placed samples in petri dishes along with a number of potentially compatible mating types, under a variety of conditions. But after five months, there was no evidence of sexual reproduction.

When the researchers sequenced the genome of T. rubrum samples, they found that the organism is very "clonal," meaning that different populations of the fungus are nearly perfect clones of one another. In fact, any two genomes of T. rubrum species are 99.97-percent identical, the researchers said.

"Such incredibly high clonality across isolates from around the world is remarkable," Christina Cuomo, senior study author and a group leader for the Fungal Genomics Group at the Broad Institute of MIT and Harvard in Cambridge, Massachusetts, said in the statement.

The researchers suspect that the ability of T. rubrum to reproduce sexually may have been lost as the species became adapted to live on humans.

The study was published online Feb. 21 in the journal Genetics.

Original article on Live Science.

Scientists in China have cloned two bouncing baby monkeys, theoretically opening the door for the cloning of humans. 

However, the researchers stressed that they have no intention of cloning humans.

"I would think that the society and general public and the government will not allow the extension of application of these methods from non-human primates to humans," said Mu-ming Poo, director of the Institute of Neuroscience at the Chinese Academy of Sciences. Instead, the goal is to create cloned monkeys that can be used to study human genetic diseases, said Poo, who co-authored a new study describing the results. [8 Mammals That Have Been Cloned Since Dolly the Sheep]

Dolly's legacy

The monkeys, both female, are named Zhong Zhong and Hua Hua from the word "Zhonghua," meaning "Chinese nation." The monkeys are currently about 7 weeks old; they live in the same kind of incubators used for human babies and are bottle-fed by human caregivers. They are very active and seem to be developing like any normal monkey, Poo said during a news conference this week.

The two big-eyed primates were created in a process called somatic cell nuclear transfer. In this method, researchers take an egg cell, or oocyte, and remove its nucleus (which holds its DNA). Then, they take a body, or somatic, cell from the individual they'd like to clone and remove its nucleus, transferring that nucleus into the empty egg. The cell is then allowed to divide and grow for several days to reach a multicell blastocyst stage. The blastocyst is then implanted in the uterus of a surrogate mother monkey to develop into a fetus and, hopefully, a baby. 

Dolly the sheep, born in 1996, was the first animal successfully cloned using this technique; specifically, she was cloned from the udder cell of an adult sheep. Dolly died in 2003 at the age of 6. Since her birth, scientists have used somatic cell nuclear transfer to clone more sheep, as well as cows, mice, rats and dogs, but no one has ever been able to clone a nonhuman primate, Poo said.

"Maybe the differentiated somatic nuclei of the primate species are unable to express the genes that are required for embryo development," he said.

Optimized process

To overcome that problem, the researchers refined their technique. They optimized the nuclear transfer with cutting-edge imaging and improved the fusion of the donor cell to the egg cell during the transfer process.

"This is a very difficult and delicate procedure," Poo said; it took many years to practice these techniques.

Even so, the reconstructed embryos failed to develop properly. The breakthrough, the researchers said, was in reprogramming the donor nuclei. They used epigenetics to do this reprogramming, meaning they altered not the DNA sequence itself but the way that individual genes were expressed. In this way, they were able to reactivate the genes required for embryonic development. The technology required to do this epigenetic modulation was developed in the past few years, said Zhen Liu, a study co-author and postdoctoral researcher at the Institute of Neuroscience. [6 Extinct Animals That Could Be Brought Back to Life]

Using connective tissue cells called fibroblasts from the fetuses of long-tailed macaques (Macaca fascicularis) as donors, the researchers created 79 cloned oocytes, which were implanted into 21 surrogate mothers. Six pregnancies took hold, and two developed to full term, the researchers reported today (Jan. 24) in the journal Cell. 

The researchers also tried cloning cells from adult monkeys, with less success. Out of 22 pregnancies in 42 surrogates, there were two live births, but both babies died soon after birth. The reason, Poo said, is likely that adult cells are harder to reprogram than more flexible fetal cells. However, the team is working on the technique and currently has female surrogates pregnant with fetuses cloned from adult body cells.

"They seem to be developing well, so we are hoping we will produce babies soon," he said.  

Besides being easier to reprogram for early-stage development, fetal cells have other advantages, Poo said: Fetal fibroblasts are easy to grow in the laboratory, and they are also easy to edit genetically. The goal, he said, is to introduce genetic mutations of the same sort that cause human diseases such as Parkinson's.

"Then, the clones will be [an] ideal model for that particular disease, for screening drugs that will cure the disease," Poo said.

The researchers hope to produce gene-edited macaque clones for use in this kind of research within a year.

Original article on Live Science. 

Purebred puppies from the same litter tend to look pretty much the same. But a trio of littermates born recently in Korea don't just closely resemble each other — they're clones that share nuclear DNA from the same cells.

In fact, those cells originated in a dog that was also a clone, making the puppies second-generation clones. The cell donor, the first cloned dog in the world, was a male Afghan hound named Snuppy (his name came from the initials of Seoul National University, the Korean institution where the research was conducted), who was born in 2005.

The three "recloned" puppies, now just over one year old, developed from stem cells harvested from Snuppy in 2010. They were described in a study that marks the first stage in documenting and analyzing their fitness, to better understand how recloned dogs fare throughout their lifetimes, the study authors wrote. [8 Mammals That Have Been Cloned Since Dolly the Sheep]

Animal cloning has existed since 1952, when scientists first cloned a tadpole by removing the nucleus from a somatic cell — any cell in the body other than a sperm or egg — and transferring it into a frog egg to replace the original nucleus, a process known as somatic cell nuclear transfer. 

But it took decades for scientists to work their way up to cloning mammals, finding their first success with Dolly the sheep in 1996. In the years since, scientists have cloned mice, pigs, cats, rabbits, goats and cattle, but the oddball reproduction of dogs presents unique challenges for cloning, according to the new study. Female dogs only come into heat once a year, and the ovulated eggs aren't ready to be fertilized immediately. Rather, the eggs mature in the oviduct as they move toward the uterus, which makes it harder for scientists to harvest them at just the right time, the study authors reported.

Snuppy was cloned from an ear cell taken from an adult Afghan hound named Tai. Tai was euthanized after a cancer diagnosis at the age of 12, and Snuppy, after a healthy life, died of cancer when he was about 10 years old, which is within the normal lifespan for the breed, the researchers noted. This suggests that clones do not necessarily experience shortened lives, as was suspected when Dolly the sheep died at the age of six (the normal lifespan for Finn Dorset sheep — Dolly's breed — is 11 to 12 years).

Snuppy's success encouraged the scientists to reclone the clone, and they implanted 94 embryos grown from his cells into seven female dogs. Four of the embryos grew to term and were healthy and normally formed at birth, but one puppy died several days later from acute diarrhea, the cause of which was unknown. The three surviving puppies are currently healthy, and based on Snuppy's life history, the researchers do not expect the reclones to suffer from accelerated aging or to be more disease-prone just because they are clones, they wrote in the study.     

"With the data from Tai and Snuppy in hand, we are excited to follow the long-term health and aging processes of these second generation of clones and work with them to contribute to a new era of studying longevity of cloned canines," the study authors concluded.

The findings were published online Nov. 10 in the journal Nature: Scientific Reports.  

Original article on Live Science.

Many mammoth questions

The road to bringing back the mammoth — a giant that went extinct at the end of the last ice age — is filled with barriers.

Scientists have pieced together the genomes of four different mammoths over the past few years, but more hurdles remain: If researchers decide to create new mammoths, how will they do it? If a mammoth calf is born, how will it learn how to behave without a parent or herd to guide it?

Beth Shapiro, a professor of ecology and evolutionary biology at the University of California, Santa Cruz, discusses these queries in "How to Clone A Mammoth: The Science of De-Extinction" (Princeton University Press, 2015). Here are 11 of the many challenges she considers, including those that are scientific, ethical and environmental.

Editor's note: This story was updated on Sept. 15, 2017, to include the fact that several mammoth genomes are now available.

DNA degradation

DNA begins to degrade the moment an organism dies. This happens because enzymes from the body cells and environment, as well as ultraviolet radiation from the sun, start to break down the genetic code. Oxygen and water can also alter DNA, breakings its strands.

Some mammoth DNA, however, has survived because it was frozen in permafrost. Some of these frozen remains contain short fragments of DNA — mostly between 30 to 90 base pairs long (one base pair is made up of two "letters" of DNA linked together: cytosine and guanine, or adenine with thymine). To put this number in perspective, there are 3 billion base pairs in the human genome.

However, researchers are working around this "short fragment" challenge by using the modern elephant genome as a scaffold, Shapiro told Live Science.

DNA contamination

Anient DNA is often contaminated with foreign DNA from fungus, bacteria, plants, animals and even from humans handling it for research purposes.

This DNA contamination can make it difficult for researchers to know which DNA molecule belongs to the animal, and which is from contamination, especially if the extinct animal doesn't have a living relative whose DNA can serve as a roadmap, Shapiro wrote.

Luckily, this isn't a big deal for mammoths, because "we can distinguish mammoth [DNA] from human and bacteria [DNA]," she told Live Science.

Close relatives

Scientists may have only fragments of mammoth DNA, but they can use DNA from the mammoth's close relatives — modern-day elephants — to help fill in the genetic gaps.

Mammoths are more closely related to Asian elephants (Elephas maximus) than they are to African elephants. Researchers in India described the Asian elephant genome in 2015 in the Journal of Biosciences, and another effort is underway at the Broad Institute in Cambridge, Massachusetts, to sequence the genome of an Asian elephant.

The mammoth and the Asian elephant diverged between about 2.5 million and 5 million years ago. If they, let's say, diverged about 4 million years ago, then about 2 percent of their genomes would be different, amounting to 70 million genetic differences, Shapiro wrote.

"The reads that I get are short, but — as long as there is a close relative that has a sequenced genome — I can still map those short reads onto that closest relative's genome and, piece by piece, put the genome together," Shapiro told Live Science in an email, referring to the "reads" of a DNA sequence. "There will be missing pieces … but it will be mostly there."

Back breeding

Scientists could try to bring back the mammoth through back breeding — that is, breeding the hairiest, most cold-tolerant Asian elephants together until generations later, a population of mammoth-like elephants emerge, according to "How To Clone a Mammoth."

There are several challenges to back breeding, however. Elephants don't reach sexual maturity until they're between 10 and 18 years old, and their pregnancies last nearly two years, Shapiro wrote in the book. This means that any back-breeding project would take a long, long time.

Furthermore, the result would not be a mammoth, but rather an elephant with mammoth-like traits. Some traits may never be passed on: Mammoth hemoglobin (the protein in blood that carries oxygen) is better suited to help large animals survive in cold climates. This hemoglobin differs from elephant hemoglobin by four mutations, but there aren't any elephants alive today that have these mutations, meaning they can't pass them on to future generations, Shapiro wrote. 

Mammoth cloning

Now that researchers have sequenced mammoth genomes (although some of these genomes might be contaminated, according to a March 2017 study in the journal PLOS Genetics), could they clone a mammoth using somatic cell nuclear transfer — the process used to make Dolly the sheep? With somatic cell nuclear transfer, scientists extract the cell nucleus (which contains DNA) from an animal, called the donor. They then insert that nucleus into the egg cell, which has had its own nucleus removed, of another animal.

It would be difficult. Cloning with nuclear transfer is not very efficient, and it's usually done with a limitless supply of cells harvested from living animals, according to "How to Clone a Mammoth." As we know, there are no living mammoths, Shapiro wrote.

Moreover, scientists would have to implant the mammoth embryo into an Asian elephant, which is endangered, largely from habitat loss and fragmentation and poaching, according to the International Union for Conservation of Nature. It would be hard to justify implanting a mammoth embryo into an elephant when every Asian elephant pregnancy counts, Shapiro wrote. 

CRISPR-Cas9

By using the gene-editing tool called CRISPR-Cas9, scientists can cut DNA in a precise location, remove genetic code and then paste that section in a new sequence created in a lab.

This method could be used to bring back the woolly mammoth in just two years' time, according to George Church, a geneticist, molecular engineer and chemist at Harvard University, who made this announcement just before the American Association for the Advancement of Science (AAAS) meeting in Boston in February 2017.

"Our aim is to produce a hybrid elephant-mammoth embryo," Church told The Guardian. "Actually, it would be more like an elephant with a number of mammoth traits. We're not there yet, but it could happen in a couple of years."

The epigenome

If a mammoth is brought back to life — through back breeding, cloning or genetic engineering — it would be challenging to recreate the creature's epigenome, which would be passed on to a developing mammoth in utero. The epigenome is a system of tags that determine which genes are turned on or off. These tags do not change the genetic code, but rather select when to activate certain genes.

An elephant epigenome would be different than a mammoth epigenome, but it's not clear what those changes are, Shapiro wrote.

It would be possible to recreate the mammoth's epigenome, Church, said at a Q&A following a panel at the American Museum of Natural History (AMNH) in April 2017, but the technology is still a ways away. 

Mammoth microbiome

Babies pick up bacteria when they exit their mother's birth canal, and continue getting new types of bacteria throughout their lives. The bacteria within and on the body is known as the microbiome, and it aids and influences digestion and health.

The mammoth's microbiome is unknown, but mammoth mummies offer hints. For instance, a necropsy (an animal autopsy) of a 42,000-year-old mummified baby mammoth showed that the youngster had feces in its digestive tract, according to "How To Clone A Mammoth."

Modern elephant calves eat their mother's feces to seed their own microbiomes — bacteria that are needed to break down the fibrous plants they eat. The finding indicates that mammoth calves did the same.

Environmental challenges

In the thousands of years since mammoths died, the environment has changed. This raises several questions, according to Shapiro: Will the new mammoths have appropriate food that they can digest?; will they be susceptible to disease, parasite or pollutants?; will the changes in temperature and precipitation impair them?

Nonetheless, two wildlife parks in Russia — Pleistocene Park and Southern Pleistocene Park — are ready to accept mammoths, should they be brought back. The goal of these parks is to turn the currently frozen Siberian tundra into pastures supported by mammoths and herbivores that once lived and supported the grassland ecosystem, according to the Pleistocene Park website.

This transformation would happen when large animals break up the ice, snow and dirt and then disperse nutrients and seeds as they roam and eat vegetation, the website reports. 

Acting like a mammoth

If scientists were to succeed in bringing back a mammoth, would the resulting calf know how to be a mammoth?

Elephants are social creatures, an indication that mammoths were too, Shapiro wrote. But without other living mammoths, it's unclear if a new mammoth would be able to behave as its predecessors did before they went extinct.

On another note, even if these calves didn't know how to act, scientists would have to breed several thousand of them, so that the newbies would have genetic diversity and become a self-sustaining population. 

Ethical dilemmas

The largest question might not revolve around the science of de-extinction, but rather whether we should attempt it.

Is it ethical to bring back an extinct animal? Should we be spending our time and resources on maintaining currently endangered animals? If de-extinction is made possible, how long are humans responsible for the animals they resurrected?

However scientists choose to move forward, it's important to engage with the public and be as transparent as possible about the parameters and goals of the project, the researchers on the AMNH de-extinction panel said. 

If scientists could resurrect extinct animals — such as the dodo, Columbian mammoth or Tasmanian tiger — should these animals have different names that distinguish them from the original species?

In a new opinion paper, a group of scientists said yes, arguing that a modified name would give de-extinct animals an appropriate distinction from the natural species, as well as a conservation status that could help protect them legally.

In practice, researchers could take the original scientific name, but add "recr," an abbreviation of "recrearis," the Latin word for "revived." This addition, for instance, would change the Columbian mammoth's scientific name from Mammuthus columbi to Mammuthus recr. columbi, said the paper's lead author, Axel Hochkirch, lab manager in the Department of Biogeography at the University of Trier in Germany. [10 Extinct Giants That Once Roamed North America]

"If the DNA amount of [a resurrected] Mammuthus columbi is not high enough [compared with the original mammoth], one could even create a new species name, [such as] Mammuthus recr. americanus," Hochkirch told Live Science in an email. "If each resurrected species is marked with "recr.," it is very clear to all that we speak about something artificial, something that differs from the real mammoth."

De-extinction techniques

There are many hurdles to bringing back an extinct species. The first animal brought back from extinction — a wild goat called a bucardo, also known as a Pyrenean ibex (Capra pyrenaica pyrenaica) — died a few minutes after its birth because of a lung defect, according to a 2009 study published in the journal Theriogenology. Likewise, efforts to bring back the extinct Australian gastric-brooding frog (Rheobatrachus silus) "were not viable," the researchers wrote in the new opinion paper.

In essence, researchers need a full copy of an extinct animal's DNA to revive that species, a difficult thing to obtain, because DNA begins to degrade the instant an animal dies. This occurs largely from exposure to bacteria, oxygen, water, ultraviolet light, and enzymes from both the animal itself and the environment, Live Science reported previously.  

But de-extinction techniques are constantly improving. These methods include back breeding (breeding an existing animal to have traits of a closely related, extinct species), cloning (putting reproductive material of an extinct species into the womb of a closely related, living species) and genomic engineering (filling in missing DNA information from an extinct species with the DNA of a closely related animal).

Because of these advances, the Species Survival Com­mission of the International Union for Conservation of Nature (IUCN) published de-extinction guidelines in 2014. While the guidelines highlight the uncertainties in classifying de-extinct animal species, the new opinion piece goes a step further, Hochkirch said.

For starters, any animal that's resurrected will likely be a hybrid of the original animal and another species, or a "proxy," for the original, he said. These differences will partly be genetic and partly due to other factors: the animal's epigenetics (environmental forces that can change gene expression), microbiome (the bacteria in the body) and learned behavior, he said.

A modified name would remind people that the resurrected animal isn't an exact copy of the original, Hochkirch said. Moreover, a revised name would remind government officials that the revived species would need extra protections, which may be different than protections that were provided to the original species, Hochkirch said. [6 Extinct Animals That Could Be Brought Back to Life]

No to "recr."

However, the new naming proposal appears to simplify how evolution works and raises questions about how the system would be implemented, said Beth Shapiro, a professor of ecology and evolutionary biology at the University of California, Santa Cruz, who was not involved with the editorial.

"How much of the genome has to be modified in order to earn the [recr] 'tag'?" Shapiro asked. "Would an elephant with two mammoth genes be considered sufficiently de-extinct? Who gets to decide?"

In an email to Live Science, Shapiro wrote, "I think 'recr' is probably inappropriate, as they are not revived copies of something, but instead hybrids. Adding this to their name will foster more misunderstanding and mistrust of the true intentions of this work, which is to facilitate the survival of species that are under threat of extinction."

The opinion piece will be published online Friday (June 9) in the journal Science.

Original article on Live Science.

20 Years Since 'Dolly'

It was 20 years ago this week that scientists announced the first successful cloning of a mammal — the now-famous sheep Dolly — from a cell taken from an adult animal. [Full story: 20 Years After Dolly the Sheep, What Have We Learned About Cloning?]

The cloning of Dolly by the team at The Roslin Institute, at the University of Edinburgh in Scotland, paved the way for researchers to try cloning a number of other mammals. Prior to Dolly, scientists had been able to clone mammals only by splitting growing embryos.

Since the announcement of Dolly's birth, dozens of other species have been cloned from adult body cells, including many mammals. Here are eight of the mammals that have been cloned in this manner since Dolly:

Pigs

In 2000, PPL Therapeutics, the same company that worked with The Roslin Institute to clone Dolly the sheep, announced that it had cloned five female piglets from adult pig cells. The piglets were named Millie, Christa, Carrel, Dotcom and Alexis. The findings were published in a 2000 paperin the journal Nature.

Cats

In 2001, researchers at Texas A&M University cloned a cuddlier animal: a cat. The kitten was born Dec. 22, 2001, to a surrogate mother, according to the findings, which were published in a 2002paper in Nature.

Though the kitten — nicknamed CC, short for Carbon Copy — was genetically identical to the cat Rainbow, the patterns on her fur looked different, likely due to developmental, rather than genetic, factors, the study said. CC had her own kittens a few years later.

Deer

Researchers at Texas A&M also cloned a white-tailed deer, nicknamed Dewey, in 2003. Dewey was born to a surrogate mother named Sweet Pea on May 23, 2003, and was cloned from skin cells taken from a deceased white-tailed buck, according to a statementat the time from Texas A&M University. Dewey is still alive today.

Horses

In 2003, researchers in Italy cloned a female horse, which they named Prometea. Interestingly, the female that gave birth to Prometea was also the donor of the genetic material, according to the study. The authors noted that the successful cloning of Prometea helped dispel notions that it might be unsafe (for immune-related reasons) for a mother to carry a fetus that was genetically identical to herself to term. Their results were published in Nature in 2003.

Dogs

Researchers in South Korea cloned a dog, according to their results published in Nature in 2005. The puppy, named Snuppy, was born April 24, 2005. He was cloned from adult skin cells taken from an Afghan hound, according to the study. Snuppy was the lone survivor after 1,095 dog embryos were implanted into 123 surrogate mother dogs, leading to just two births (the other puppy died a few weeks later), according to the article. In 2008, Snuppy fathered his own puppies, the article said.

Mice

In 2008, researchers in Japan announced that they had cloned mice using cells that had been frozen at minus 4 degrees Fahrenheit (minus 20 degrees Celsius) for 16 years. After thawing these cells, researchers found that all of them had ruptured, but the scientists were still able to extract the DNA required to produce healthy cloned mice, according to the study, published in 2008in the journal Proceedings of the National Academy of Sciences. The scientists wrote that they hoped that this might indicate that it would be possible, in future, to "resurrect," certain animals or keep stocks of frozen tissue to use later, the study said.

Wild goats

In 2009, resurrection science got another boost: Scientists reported that, for the first time, they had cloned an extinct mammal, the bucardo (a type of wild goat also called a Pyrenean ibex). The group of researchers, with members from Spain, France and Belgium, used cells from preserved samples from a bucardo captured in 1999 to produce the cloned animal, according to the study. However, the young goat died only minutes after its birth because of defects in her lungs. The research was published in 2009in the journal Theriogenology.

Gray wolves

In 2005, South Korean researchers cloned the endangered gray wolf, producing two young pups: Snuwolf and Snuwolffy. One pup was born Oct. 18, 2005, and the other was born Oct. 26, 2005. The two cloned wolves were produced from genetic material taken from the ear cells of a female gray wolf. However, researchers used eggs from dogs to host the genetic material in order to bring the cloned animals to term, because it was difficult to obtain this material from gray wolves in the wild, the study said. Dogs were also used as the surrogates for the wolf pups, according to the study, which was published in the journal Cloning and Stem Cells in 2009.

Originally published on Live Science.

Today marks the 20th anniversary of the announcement of Dolly the sheep, the first mammal cloned from an adult cell. Her creation left a lasting impact on both the public and the field of developmental biology, experts say.

At the time, other researchers had managed to clone mammals by splitting embryos in a test tube and implanting them in adults. However, none had successfully used an adult somatic (body) cell to clone a mammal. Researchers at the Roslin Institute in Scotland were finally able to produce Dolly — cloned from the udder cell of an adult sheep — after 276 attempts, according to the National Human Genome Research Institute (NHGRI).

"For a developmental biologist, the ability to clone an advanced mammal was thought to be impossible," Lawrence Brody, director of the Division of Genomics and Society at the NHGRI, told Live Science.

Although Dolly was born in July 1996, Researchers announced Dolly's existence on Feb. 22, 1997. The delay in the announcement was due to the time needed to amass sufficient data on the project, check the data, write and get the manuscript published, said Bruce Whitelaw, the head of the Division of Developmental Biology at the Roslin Institute. [5 Fascinating Findings About Stem Cells]

Although British biologist John Gurdon had cloned frogs from the skin cells of adult frogs in 1958, researchers after him had failed to clone mammals such as mice, rats and pigs, despite trying for decades, Brody said. He added that many researchers began to feel there had to be "something different about mammals in the way their genome and genetic blueprints are packaged," and that cloning them would be impossible.

However, Dolly's creation "told us that was all wrong," Brody said.

That breakthrough would be crucial in the years to come. "It is rare that a single scientific story can have such a rapid, then sustained, impact" on science, Whitelaw said. Dolly had a massive scientific impact, especially through driving stem cell research and therapy, Whitelaw told Live Science.

Ian Wilmut, the scientist who led the team that created Dolly, similarly told Live Science that research on Dolly led to both unexpected and very important results. "The birth of Dolly and the new understanding of the opportunity to change the functioning of cells made researchers consider other possible ways of modifying cells," Wilmut said. Later, in 2006, researchers in Japan found that introducing a set of four proteins into these skin cells led to a portion of them to "become very similar to embryo stem cells," where they had the ability to then differentiate into different adult cell types, Wilmut said.

"The whole stem-cell investigation was really stimulated by the fact that Dolly was able to be born, and stem cells still are quite promising as a means to be able to repair human tissues when they're damaged," Brody said. "We're obviously not there yet, but it is something that could be traced back to the success of Dolly."

There is also a link between the Dolly experiments and the so-called CRISPR technologies that allow scientists to edit genomes, Brody said: Both are breakthroughs of enormous magnitude, and could help researchers figure out ways to repair damaged or diseased tissues, he said. [Unraveling the Human Genome: 6 Molecular Milestones]

Another important result of the Dolly experiments is that they put science in the spotlight. "Dolly captured the world's imagination and allowed the world to hear about science," Brody said. "It's rare that the general public gets enamored [with] science, and it was clearly enamored with Dolly". The creation of Dolly also brought up important conversations about the ethical limitations of manipulating human cells and embryos, laying the groundwork for similar conversations today, Brody said.

Dolly died in February 2003, at age 6. (A typical life span for a sheep is about 10 to 12 years.) She had both offspring and clone "sisters," which were derived from the same batch of cells as Dolly. However, none of her offspring are alive today, Wilmut told Live Science. (Whitelaw also mentioned that the Roslin Institute no longer keeps sheep, as the funding for this program has run out.)

Since Dolly's creation, numerous other mammals have been cloned successfully, including mice, cattle, deer, horses and rats, according to the NHGRI.

Originally published on Live Science.

Woolly mammoths were extinct, shaggy beasts that were relatives of today's Asian elephants (Elephas maximus). They lived across North America and Eurasia for about 700,000 years and went extinct around 4,000 years ago.

Scientists know so much about these elephant-relatives because many of their bodies have been found, frozen and preserved in the ground in Siberia, Alaska and Canada. Some of these mammoths look like they died only recently, with fresh-looking skin, hair and tusks. From these amazing finds, we know what adults and babies ate, how far they walked, how they died, and how they're different from modern-day elephants.

Even though they're long gone, some scientists are trying to clone the ice age beasts. They hope to bring the mammoths back to places like Siberia and Alaska, where they once lived.

3 fun facts about woolly mammoths

• Mammoths walked huge distances: If woolly mammoths walked in a straight line they could have circled the Earth twice
• Necropsies, or autopsies for animals, show that babies drank their mother's milk. But they also ate grass and even poop. And mammoths also ate flowers that were packed with protein
• They had tiny ears — about the size of dinner plates — compared with their relatives that lived in warm places. Smaller ears meant less surface area to lose heat, so their ears shrunk over time to adapt to living in colder places.

Everything you need to know about woolly mammoths

Woolly mammoth taxonomy

Domain: Eukaryota

Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Proboscidea

Family: Elephantidae

Genus: Mammuthus

Species: Mammuthus primigenius

Woolly mammoth pictures

Discover more about woolly mammoths

—How many animal species have humans driven to extinction?

—Pleistocene epoch: The last ice age

—Frozen in time: 10 prehistoric animals found trapped in ice

Four cloned sheep that are genetically identical to Dolly, the first cloned mammal, are still healthy even in old age, a new study found.

The four sheep, which were derived from the same batch of cells as Dolly and could be considered her clone "sisters," have just reached their 9th birthday, which is equivalent to age 70 in human years, researchers who have been studying the sheep said.

A detailed study of these four sheep and nine other cloned sheep that are not related to "the Dollies" found that the animals were healthy. All of the sheep were free from many diseases commonly found in older sheep, such as diabetes and high blood pressure, the study showed.

The findings suggest that cloned animals that live to an old age aren't at increased risk for long-term health problems, the researchers said.

"Despite their advanced age … none of the clones showed any clinical signs of disease," the researchers at the University of Nottingham in England, wrote in the July 26 issue of the journal Nature Communications. [6 Extinct Animals That Could Be Brought Back to Life]

Dolly was born in 1996 as the result of a lab technique called somatic-cell nuclear transfer (SCNT), in which the nucleus from an adult cell is implanted into an egg cell that doesn't have a nucleus. This meant that Dolly was a clone, genetically identical to the adult sheep from which the cell nucleus came.

Dolly lived to be 6.5 years old and died in 2003 from a type of lung cancer that is caused by a virus and affects sheep. Before her death, Dolly developed arthritis at a relatively young age and had trouble walking. This caused concerns that clones might be at increased risk for age-related diseases. But until now, no detailed studies of age-related diseases in cloned animals had been conducted, the researchers said.

In the new study, 13 cloned sheep underwent a series of health tests, including tests of their blood glucose levels, blood pressure, body fat composition and walking ability. The animals also underwent X-rays and MRIs to assess their bone and muscle health.

The test results were normal for the sheep's age. Some of the sheep had signs of mild arthritis, but this would be expected in older sheep, and none of the sheep needed treatment for the condition, the researchers said.

"From the current series of assessments, we conclude that there are no long-term detrimental health effects of cloning by SCNT for a long-lived species such as the sheep," the researchers said.

The cloning procedure itself comes with a high risk of death or developmental abnormalities in the fetus. But for the clones that survive, the new data suggests that "they are healthy and seem to age normally," the researchers said.

Original article on Live Science.

Scientists are one step closer to bringing a woolly mammoth back to life.

A new analysis of the woolly mammoth genome has revealed several adaptations that allowed the furry beasts to thrive in the subzero temperatures of the last ice age, including a metabolism that allowed them to pack on insulating fat, smaller ears that lost less heat and a reduced sensitivity to cold.

The findings could enable researchers to "resurrect" the ice-age icon — or at least a hybridized Asian elephant with a few of the physical traits of its woolly-haired cousin, said study co-author Vincent Lynch, an evolutionary biologist at the University of Chicago.

"It won't be that long till we're technically able to do it, but whether we should is a different question," Lynch told Live Science, referring to cloning a mammoth. "I don't think we should." [6 Extinct Animals That Could Be Brought Back to Life]

Cold-adapted creature

The mammoth DNA was extracted from the hair of two mammoths found in Siberia several years ago. One mammoth died about 20,000 years ago, and the other died 60,000 years ago. (The shaggy beasts flourished on the ice-age tundra, but most of them died after the glaciers melted, by about 10,000 years ago. A few holdouts survived on Wrangel Island off Siberia until about 3,700 years ago.)

Because mammoths and Asian elephants shared a common ancestor roughly 5 million years ago — a blip, in evolutionary time — the team was able to compare the genome of the ice-age beasts with their modern-day cousins, the Asian elephants. [How to Bring the Woolly Mammoth Back (Infographic)]

"They're really closely related," Lynch told Live Science.

They found that several unique mammoth genes helped the cold-loving creatures survive. These included genes for their shaggy, curly, heat-trapping fur, as well as for their small ears and short tails, which lose less heat than the big ears and tails that keep elephants cool.

The pudgy ice-age pachyderms also had genetic differences from the Asian elephant in the way they stored fat and processed insulin, the hormone that regulates how the body uses blood sugar for energy, according to the study, which was published today (July 2) in the journal Cell Reports. Because fat is insulating, the animals' chubby physiques helped them weather the Arctic tundra, which could routinely plunge to minus 58 degrees Fahrenheit (minus 50 degrees Celsius), according to the study.

Mammoths and elephants also had different temperature-sensing receptors in the body. In the mammoth, the receptors were essentially turned down, like a dimmer switch. That likely made the shaggy creatures less sensitive to both heat and cold, Lynch said.

Bringing mammoths back

The new findings bring the world closer to a cloned mammoth, but don't expect a genetically authentic version of the beast to come roaring back to life anytime soon.

Instead, researchers will first try to create a cold-resistant hybrid between an Asian elephant and a woolly mammoth, said George Church, a geneticist at Harvard University who is not involved in the current study.

Sequencing the genome is not the hardest part of the process; assembling a whole genome from scratch that actually functions like natural genetic material is more difficult, said Church, who is working on a project to bring the extinct creatures back to life.

Instead of trying to create a 100-percent authentic mammoth, Church's team is using a genetic cut-and-paste tool called CRISPR to splice a handful of mammoth genes into Asian elephant cells.

"We thought we'd just make the changes that are most likely to lead to an animal that looks, behaves and is adaptable to the cold like a mammoth," Church told Live Science.

Modifying Asian elephants with mammoth genes could help the modern-day subtropical creatures live in colder locales, "possibly extending the geographical range of an existing endangered species northward to areas at much lower risk of conflict with humans," Church said.

Follow Tia Ghose on Twitter and Google+. Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.

A woolly mammoth carcass recently unearthed in Siberia could be the best hope yet for scientists aiming to clone the massive, long-extinct beast.

The mammoth specimen, which was discovered in 2013 in a remote part of Siberia, oozed a deep red liquid when it was first discovered. Scientists have now analyzed the mammoth to understand how it lived and died — and whether it will yield enough undamaged DNA to make cloning the extinct creature a reality.

Details from the mammoth autopsy will air in the Smithsonian Channel special called "How to Clone a Woolly Mammoth," on Nov. 29 at 8 p.m. ET/PT. (Warning: This story contains some spoilers about the Smithsonian Channel special.) [See Images from the Woolly Mammoth Autopsy]

Stunning find

In May 2013, scientists from the Siberian Northeastern Federal University crossed the icy expanse of Siberia to reach Maly Lyakhovsky Island in the far north, where rumor had it a mammoth was lurking in the permafrost. At the time, two giant tusks were poking out of the ground, but when the researchers dug further, they found an almost complete mammoth, with three legs, most of the body, part of the head and the trunk still intact.

During excavations, the carcass oozed a dark red liquid that may have been fresh mammoth blood. In fact, the mammoth meat was reportedly fresh enough that one of the scientists took a bite of it.

"This is definitely one of the best samples people have ever found," Insung Hwang, a cloning scientist at the SOOAM Biotech Research Center, said in the show.

In the past, mammoths have yielded only a few dried specks of blood, and none of them left enough intact DNA for a cloning experiment.

Life and death

The researchers then took the carcass to Yakutsk in Russia, where a group of experts had just three days to thoroughly examine the specimen before it was refrozen to prevent rotting. The team used carbon dating to determine that the female mammoth, nicknamed Buttercup, lived about 40,000 years ago. Tests conducted on the mammoth's teeth revealed it was likely in its mid-50s.

Based on growth rates from the tusks, the team deduced that the mammoth had also successfully weaned eight calves and lost one baby. Feces and bacteria in the intestines revealed the ancient matriarch ate grassland plants such as buttercups and dandelions.

Tooth marks on her bones helped the scientists glean information about Buttercup's grisly end. The mammoth had become trapped in a peat bog and was eaten alive from the back by predators such as wolves.

While scientists probed the elbow of the mammoth, the large beast oozed more blood. Chemical analyses revealed that the blood cells were broken, but still contained hemoglobin, or oxygen-ferrying molecules. Unlike humans and other mammals, mammoths evolved a cold-resistant form of hemoglobin that could survive at the near-freezing temperatures present during the Ice Age.

"The fact that blood has been found is promising for us, because it just tells us how good of a condition the mammoth was kept in for 43,000 years," Hwang said.

Cloning a mammoth?

But whether or not Buttercup can be resurrected is another matter.

DNA is fragile and must be stored at low temperatures and in uniform humidity to stay intact. Past mammoth carcasses have looked exceptionally well-preserved, with some even yielding a preserved mammoth brain. Others have oozed what looked like blood, but ultimately did not have enough DNA to recreate the mammoth genome and clone it.

So far, the team hasn't found a complete copy of the mammoth's genome. But Buttercup's tissue has revealed some very long fragments that could potentially be pieced together to recreate the genome. Still, researchers are continuing to hunt for a complete copy.

Yet, even if a complete sample of undamaged DNA can't be found, there may be other ways to clone a mammoth, said Harvard University researcher George Church. He is hoping to combine DNA from Buttercup with modern-day elephants, essentially grafting the DNA for hair, tusks and other distinctive mammoth features into the genome of the animal's modern-day relatives.

Follow Tia Ghose on Twitter and Google+. Follow Live Science @livescience, Facebook & Google+. Originally published on Live Science.

In May 2013, scientists from the Siberian Northeastern Federal University  heard that mammoth tusks were sticking out of the permafrost on Maly Lyakhovsky Island in nothern Siberia. Researchers crossed miles of ice to see for themselves, and soon found the tusks belonged to a mammoth that had been exceptionally preserved beneath the permafrost. Mammoth experts performed a thorough autopsy on the animal, revealing intimate details of its life and grisly death. The carcass, which oozed fresh blood when it was first dislodged from the permafrost, is perhaps the best hope of cloning a mammoth yet. [Read the full story on the mammoth autopsy]

Frozen in time

When the team dug up the carcass, they found that almost all of the carcass was intact, with three legs, the majority of the body, part of the head and the trunk still present. The carcass also oozed a dark red liquid, which researchers hoped was blood. The carcass was so well preserved that a scientist took a bite of it. (Photo credit: Semyon Grigoriev/Northeastern Federal University in Yakutsk)

Mammoth autopsy

The scientists from Siberia soon realized what an exciting find they had. They convened a group of mammoth experts to conduct an autopsy on the extinct beast over a three-day period as the carcass thawed out. Carbon dating of the tissue revealed that the mammoth lived and died about 40,000 years ago. The team also recreated the mammoth's gruesome last moments: It was eaten alive by wolves and other predators after getting stuck in a peat bog. (Photo credit: Renegade Pictures)

Giant teeth

The team also analyzed the teeth of the ancient mammoth, which the teem nicknamed Buttercup. Because elephants typically replace their molars about six times in their lives, identifying which pair of molars the mammoth had, as well as studying the wear on those teeth, can reveal soemthing about the mammoth's age. In this case, the team determined that Buttercup was in her mid-50s when she died. (Photo credit: Renegade Pictures)

Cold blood

When scientists conducted the autopsy, they managed to obtain a vial of blood from Buttercup. Though the blood cells are no longer intact, the sample still contains the oxygen-ferrying molecule hemoglobin. Mammoths had a special form of hemoglobin that still worked at near-freezing blood temperatures as blood flowed from the heart to their feet. Here, Roy Weber, a researcher at Aarhus University, Denmark, holds up a vial of Buttercup's blood. (Photo credit: Renegade Pictures)

Great tusks

Here, paleobiologist Tori Herridge of the Natural History Museum, London, poses with Buttercup's tusks. Herridge was one of the scientists involved with the mammoth autopsy. (Photo credit: Renegade Pictures)

Cloned mammoth

The exceptionally preserved mammoth may be the best chance yet of cloning the extinct creatures. Here, cloning scientist Insung Hwang of SOOAM Biotech Research Center in South Korea, stands with the carcass. Despite its amazing preservation, finding enough intact DNA to completely recreate the genome of the mammoth is an incredibly difficult task, and so far, a complete genome has proved elusive. (Photo credit: Renegade Pictures)

Face to face

While the entire team hopes to find enough DNA to clone a mammoth from scratch, that could be tricky. For one, DNA is delicate and must be stored at cold, constant humidity in order to be preserved. Harvard University researcher George Church hopes to overcome those challenges one way or another. (Photo credit: Renegade Pictures)

Woolly elephant?

If an entire, intact mammoth genome can't be found from tissue in Buttercup's carcass, Church is investigating other ways to  recreate the extinct behemoths. His team has developed a method for precisely targeting key snippets of mammoth DNA into the genome of the elephant. These modern-day hybrids would have the hair, tusks, blood and other characteristic features of a mammoth, though much of the genome would be the elephant's. (Photo credit: Renegade Pictures)

Follow Tia Ghose on Twitter and Google+. Follow Live Science @livescience, Facebook & Google+. 

Stem cells can be created in a way that sharply reduces the risk of these cells dividing haphazardly and becoming cancerous, according to a new study. This potential for stem cells to become cancerous is a danger that plagues stem cell research.

The researchers published their new method today (Dec. 17) in a video article, akin to a cooking demonstration that shows other scientists how to make these stem cells, in the Journal of Visualized Experiments (JoVE).

The research group, led by Dr. Kostas Kostarelos of the University of Manchester in England, built upon a technique developed by Shinya Yamanaka of Kyoto University in Japan, who won the 2012 Nobel Prize for his work.

As with Yamanaka's approach, Kostarelos' new technique creates stem cells called induced pluripotent stem (iPS) cells. These iPS are ordinary adult cells, such as skin cells, that have been transformed into an embryonic state, and that can be reprogrammed, in theory, to become any other kind of cell, such as nerve or heart cells.

Yet the difference between the approaches is twofold: In the new technique, Kostarelos' team uses a ringlet of DNA called a plasmid, instead of a virus, to bring the genetic instructions into a cell so that it can become a stem cell; and his team did this in a live mouse, instead of in a dish of cells.

They have successfully transformed ordinary liver cells into iPS cells, with no signs of subsequent cancer development. [Video: Stem Cell Production Technique]

Embryonic state

Scientists classify the natural stem cells in mammals into two broad categories: adult stem cells and embryonic stem cells. Adult stem cells are found in various tissues and replenish the cells found in those specific tissues, such as skin or blood.

Embryonic stem cells are from the embryonic stage of development, and can differentiate into all the varied cells found in a complex organism, from the brain down to the toes. Doctors have hoped to use embryonic stem cells to essentially repair damaged tissue — injecting them into a spinal cord, for example, to grow new nerve cells after paralysis.

However potent for curing diseases, human embryonic stem cells originate from discarded embryos created in fertilization clinics; and there is debate about the ethics of using such embryos in research or treatments.

Yamanaka's relatively simple method to create iPS cells is considered revolutionary because no embryos are destroyed, thus bypassing this thorny ethical issue. Yamanaka discovered four genes that could be switched on to make an ordinary cell become more like an embryonic cell.

The only snag has been that researchers have difficulty controlling this change. The iPS cells often continue to divide and produce a tumorlike mass. This is because the virus used to bring the four key genes into a cell also can introduce other genetic information that causes mutations, or the pluripotent state of the cells persists for too long.

A fresh approach

Using a plasmid ferry instead of a virus reduces these risks because the plasmid is shorter-lived, and does not integrate its genetic information to pollute the host cell. Yamanaka and others tried using plasmids instead of a virus in laboratory cell cultures as early as 2008, but met with limited success.

Kostarelos' team took a fresh approach, injecting a specific configuration of gene-carrying plasmids directly into a mouse.

"We just asked a different question: 'Can we achieve cell reprogramming… within the tissue of a living animal, without inducing tumor growth?'" Kostarelos told LiveScience. "The answer to this question is yes, we can," as long as a cell's genetics are not changed permanently, he said.

The JoVE video is a follow-up to a paper that Kostarelos and colleagues at University College London published in the journal PLOS ONE earlier this year. Kostarelos said he wanted to show the technique via JoVE to teach others this straightforward method.

Kostarelos added that all forms of stem cells remain vital for research in the emerging field of regenerative medicine.

"Embryonic stem cells are very much needed as we develop and understand the iPS cell technology better," he said.

Follow Christopher Wanjek @wanjek for daily tweets on health and science with a humorous edge. Wanjek is the author of "Food at Work" and "Bad Medicine." His column, Bad Medicine, appears regularly on LiveScience.

Editor's Note: In this weekly series, LiveScience explores how technology drives scientific exploration and discovery.

The passenger pigeon, the dodo and the woolly mammoth are just a few of the species wiped off the Earth by changing environments and human activities.

Now, advances in biotechnology could enable scientists to bring extinct animals back from the grave. But critics argue the practice would only hinder conservation efforts, by resurrecting creatures that could not survive in the wild.

First popularized by Michael Crichton's novel "Jurassic Park," the process of de-extinction has become more than a sci-fi concept. In 2003, biologists brought back a Pyrenean ibex by making a clone of frozen tissues harvested from the last of these goats. The clone died within minutes of its birth due to a lung deformity, but the experiment proved de-extinction was possible. [6 Extinct Animals That Could Be Brought Back to Life]

"We can use some of these techniques to actually help endangered species improve their long-term viability," said ecologist Stanley Temple of the University of Wisconsin-Madison. "Where it gets controversial is when we start talking about species that have been extinct for a very long period of time," Temple said.

Reviving the passenger pigeon

The passenger pigeon filled the skies of North America in flocks of millions during the 19th century. But hunting and habitat destruction steered the birds to extinction. The world's last passenger pigeon, Martha, died in 1914 at the Cincinnati Zoo in Ohio.

But what if scientists could bring them back? Writer and environmentalist Stewart Brand, founder of the Whole Earth Catalog, and his wife Ryan Phelan, founder of the genetics company DNA Direct, wondered if it were possible. Working with Harvard biologist George Church, they figured out a possible way to revive passenger pigeons.

You can't simply clone a passenger pigeon museum specimen, because they no longer have fully intact genomes. But there could be another way: Using fragments of the passenger pigeon DNA, scientists could synthesize the genes for certain traits and splice the genes together into the genome of a rock pigeon.

The cells containing the passenger pigeon DNA could be transformed into cells that produce eggs and sperm, which could be injected into rock pigeon eggs. The pigeons that hatched would be rock pigeons, but their offspring would resemble passenger pigeons. Scientists could then breed these birds and select for specific traits, as a dog breeder might. Eventually the resulting offspring would appear very much like the passenger pigeon.

But that's not the only extinct animal scientists have their sights on reviving.

Woolly mammoths next?

Other scientists dream of bringing back a beast that roamed the Earth hundreds of thousands of years ago: the woolly mammoth. Well-preserved mammoths have been dug out of the Siberian tundra containing bone marrow, skin, hair and fat. If a living mammoth cell were found, it could be grown in a lab and coaxed to form an embryo. The embryo could be implanted into the closest living relative of mammoths, an elephant, which would give birth to a baby mammoth. [Images: 25 Amazing Ancient Beasts]

Finding a living mammoth cell is very unlikely. But South Korean biomedical engineer Insung Hwang hopes to find just a cell nucleus and produce a clone from it, like Dolly the sheep. The nucleus would be implanted into an elephant egg whose nucleus had been removed. But this is no easy feat — no one has yet successfully harvested an elephant egg.

The challenges aren't trifling. Even if researchers succeed in creating a mammoth, passenger pigeon or other extinct creature, it has to survive in the wild. This means having the right food and habitat, and evading predators — especially humans.

Conservation controversy

Critics of de-extinction say reviving extinct animals would do more harm to conservation efforts than good.

"I don't think it has any merit at all," said conservation ecologist Stuart Pimm of Duke University, N.C. "It totally ignores the very practical realities of what conservation is about."

The prospect of bringing species back from extinction would lead Congress to support the destruction of natural habitats, because animals that go extinct could be revived in a lab, Pimm told LiveScience.

Most species are going extinct in tropical forests, Pimm said. Saving a species through de-extinction when humans are burning forests and destroying native communities is a joke, he said.

Biologist David Ehrenfeld of Rutgers, The State University of New Jersey, agrees de-extinction would impede conservation. "It's very negative, very expensive and not going to achieve any conservation goal as far as I can see," Ehrenfeld said.

For example, the passenger pigeon was a very social bird known to form flocks of millions. When their numbers dwindled to a few thousand, the birds stopped breeding, Ehrenfeld told LiveScience. De-extinction methods would produce just a handful of birds, so "who's to say they would reproduce?" he said.

What's more, the pigeons that raised them would be a different species, with differing mothering techniques. "The environment is different in every respect," Ehrenfeld said.

Temple took a more moderate view. "If we're going to try to do this seriously, it's probably in everyone's best interest that the early attempts have a high probability of success," he said.

Resurrecting a creature like the passenger pigeon or woolly mammoth has a strong appeal to the public's imagination, Temple said. "But the species that are often hyped don't meet those criteria at all," he said.

Editor's Note: This article was updated at 11:45 a.m. ET August 19 to correct the age when woolly mammoths existed.

Follow Tanya Lewis on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on LiveScience.

Mammoth unearthed

In May 2013, researchers Semyon Grigoriev and colleagues at North-Eastern Federal University in Yakutsk recently unearthed an astonishingly well-preserved mammoth carcass on an island off the coast of Siberia.

Fresh blood

The researchers said the carcass, which had been partially buried in the ice, was so well preserved that it contained flowing blood.

Oozing blood

When the team struck at it with a pick, blood flowed from the carcass.

Pristine condition

The blood found suggests that the mammoth was possibly the best preserved mammoth found.

Tissue find

But though the blood is a promising sign, there's no telling whether the cells inside the mammoth are in good enough condition to yield usable DNA. The ultimate goal is to clone a woolly mammoth.

Partially eaten

The team estimates that the mammoth lived about 10,000 years ago. The upper torso and legs were gnawed on by predators.

Carrying back

After the discovery, the researchers carried the mammoth across the frozen terrain on a sled.

Research hopes

If the team finds intact white blood cells or tissue cells, they may be able to extract relatively long segments of DNA. Still, it's incredibly unlikely that the material will be in good enough condition to make cloning a mammoth a reality.

Cloned creature

South Korean, Japanese and Russian teams are working to clone a mammoth by piecing together snippets of DNA found in mammoth fossils using the elephant genome as a template. Afterwards, they would inject mammoth DNA into the egg of an elephant and have an elephant gestate the extinct creature for 22 months.

The second coming of Jesus Christ may be on the horizon — along with the third, fourth and fifth incarnations, depending on how quickly an artist's new "cloning tincture" catches on.

Conceptual artist Jonathon Keats is giving everyone the chance to become the Christian messiah — and a number of other historical personages and celebrities as well — through his Epigenetic Cloning Agency, which opens a new branch at a Berlin gallery today (May 31).

To be clear: The Epigenetic Cloning Agency is an art project whose concoctions are meant to inspire thought and conversation about the nature of identity and the march of scientific progress, not actually turn you into someone else. In fact, the potions aren't even meant for human consumption.

Keats is dedicating the Berlin office tonight with a reception that will serve a cocktail specially designed to create clones of himself. This drink is much cruder than his fine-tuned tinctures, Keats said, but he thinks it will serve his purposes well. [How Stem Cell Cloning Works (Infographic)]

"It seemed that having a cocktail, a drink that anybody could make at home — that would be a much more efficient way to go about making myself legion," Keats told LiveScience.

Epigenetic cloning basics

Scientists have cloned organisms before, generally by injecting the nucleus of a donor cell into an egg whose own DNA has been removed. Dolly the sheepwas famously cloned using this method in 1996.

But epigenetic cloningtakes a different tack, seeking to alter how a customer's genes are expressed rather than swapping out his or her entire genome. The technique draws its inspiration from the big and burgeoning field of epigenetics, which is revealing the importance of environmental factors in shaping who we turn out to be.

For example, the recipe for becoming Jesus Christ includes, among other things, some basic components of the Mediterranean diet of the time and substantial doses of omega-3 fatty acids (he likely ate a lot of fish), Keats told LiveScience back in October at the opening of the San Francisco branch of the Epigenetic Cloning Agency.

The concoction also sports a healthy dose of iron, because "there were nails involved," Keats said.

"Probably the most important ingredient of all, though, is placebo," he added. "The amount of faith that he seems to have had was vast."

A diverse lineup

The Epigenetic Cloning Agency's Berlin branch will be offering several other tinctures in addition to the Jesus mixture, including Napoleon Bonaparte, Queen Elizabeth I, Lady Gaga, swimmer Michael Phelps and Angela Merkel, the current chancellor of Germany. All of these bottles will sell for 15 Euros (about $20 at current exchange rates). [Trippy Tales: The History of 8 Hallucinogens]

Keats consulted European gossip magazines to get an idea of what Merkel likes to eat. He said he devised a potion containing lots of starch, sodium and cholesterol, among other ingredients, after learning of the chancellor's fondness for minced pork sausage and a meaty, sour soup called solyanka.

The list of Berlin offerings is just a starting point, Keats said. The Epigenetic Cloning Agency is willing to tailor tinctures to their customers' desires, and it will even take a stab at fictional characters such as Sherlock Holmes if asked to do so.

"In a sense, I guess, you would be a more realistic version of that character," Keats said. "As a living person, you would be able to live that life more fully than Arthur Conan Doyle could ever have imagined," said Keats, referring to the author of the Sherlock Holmes novels.

Epigenetic effects are felt most profoundly in the early stages of an organism's development, so adults shouldn't expect a sudden and dramatic transformation into Napoleon, Jesus or anyone else, Keats told LiveScience in San Francisco

"This is going to work a lot better when you're younger," he said. "In utero is the best time to approach me."

Ethical questions

The Epigenetic Cloning Agency's activities are intended to raise some of the ethical and philosophical questions that would apply if humanity ever does develop the technology to clone individual humans, dead or alive.

For instance, what motivates people who want to become a Merkel clone? Is imitation the sincerest form of flattery, as the saying goes? Or do these folks seek to replace her or absorb her strength and power, as warriors once tried to do by eating the hearts of their fallen foes?

The cloning of Christ is a particularly tricky area, of course. With many Jesuses running around, which one — if any — would believers follow? Could any of these messiahs be legitimate, or would they need the genealogical bona fides that the original Jesus boasted?

"All of these questions about how you relate to these iconic figures — who they are and what makes them who they are, what made them who they were — all of those questions, I think, are available for discussion by way of the cloning agency," Keats said. "And by allowing people to partake of it — to really become the epigenetic clone of Christ rather than simply talking about it around a table — I think that it raises the stakes."

The Epigenetic Cloning Agency will be open for business at the Team Titanic gallery in Berlin through June 8.

Follow Mike Wall on Twitter @michaeldwall and Google+.  Follow us @livescience, Facebook & Google+. Original article on LiveScience.com.

Puppy lovers in the United Kingdom may soon get a chance to extend their dog years, thanks to an odd new contest: A South Korean company wants to clone the most beloved U.K. pooch — again raising ethical questions about the practice of pet cloning.

Headed by a former stem-cell researcher named Woo-Suk Hwang, the Sooam Biotech Research Foundation has been cloning dogs and other animals for years, mostly for U.S. customers. Now, in an effort to expand into the British market, the lab has asked U.K. canine owners to submit a 500-word essay, along with photos and videos, demonstrating why their best friend's genes should live on, Sooam researcher Hanna Heejin Song wrote in an email to LiveScience.

The chosen dog owner gets 70 percent off the usual $100,000 price tag for replicating Rufus. [10 Things You Didn't Know About Dogs]

Cloning Fido

The process then follows the now-established outline for animal cloning: Sooam researchers will perform a biopsy to extract a viable skin cell from the dog, inject DNA from that cell into another dog's egg cell (one that has been emptied of DNA) and implant the resulting embryo into the womb of a surrogate canine mother.

When successful, the process births a cloned puppy about two months after implantation, Sooam's website says. That "successful" part usually takes several attempts, though — and several dogs are needed as egg donors and surrogate mothers. In the early days of dog cloning, it took at least dozens of egg donors, said John Woestendiek, author of "Dog, Inc." (Penguin Group, 2010), which investigates the world of dog cloning. "It's down to a handful now."

As if photocopying Fido weren't strange enough, the contest comes from the lab of Hwang, who earned first fame, and then infamy, for falsifying research data, claiming to have cloned human embryonic stem cells in 2004. Hwang was convicted in 2009 on several counts related to the bogus research.

Nevertheless, Hwang's company has successfully reunited several pet owners with genetic copies of their furry companions. Hwang led one of the first successful attempts at dog cloning when he replicated a pooch named Snuppy in 2005. Sooam researchers have also cloned wolves and coyotes. And last year, the company announced plans to try to “bring back” a woolly mammoth from extinction. The feat would require extracting DNA from frozen mammoths and incubating an embryo in an elephant surrogate mother. [6 Extinct Animals That Could Be Brought Back to Life]

Ethics of dog cloning

Successes aside, Hwang's cloning endeavors still raise ethical concerns, Woestendiek said. First, the massive expenditure of money and scientific resources involved in cloning may look irresponsible when there are so many dogs languishing in shelters.

"Why go to all that expense if there are dogs that need homes?" Woestendiek asked. In the United States alone, 6 million to 8 million cats and dogs enter shelters each year, according to the Humane Society of the United States.

And, in most cases, it's pretty easy to find a new dog that looks like the old one, Woestendiek said. Cloning, after all, can only really replicate looks. The new dog is not, by any means, the "same" pet, and may behave differently, the author said.

"I think that personality is really what most people are looking to clone," Woestendiek noted. "And I don't think personality is clone-able." That's because though the clone should have a complete DNA match with the late dog, personality is the result of genes, upbringing and environment.

Dog cloning also raises concerns about the treatment of egg donors and surrogate mothers. U.S.-based company BioArts International left the pet-cloning business, in part, because of ethical questions about how its South Korean partners treated surrogate animals, according to a company statement. South Korea lacks the oversight that protects research animals in the United States, Woestendiek said. And, though it reportedly doesn't happen much anymore, some of the surrogate dogs used in Korea have gone to "farms" — meaning they were then raised for their meat, Woestendiek added.

The dog owners who have gotten their pets cloned, however, seem "totally pleased" with the results, Woestendiek said. The whole spectacle just shows how much dog lovers care about their canine companions. "Dogs are more like children than pets now," he said.

The U.K. contest echoes some of the first forays into commercial pet cloning in the Americas, Woestendiek said. In 2009, Nova Scotia resident John Symington won the right to clone his German shepherd Trakr in the "Golden Clone Giveaway," hosted by BioArts, which contracted the actual work to Hwang's lab. Symington claimed Trakr, a rescue dog, had found the last survivor of the attack in New York.

Applicants to the new contest must be U.K. residents, and they have until July 1 to make submissions to dogcloning@gmail.com. Sooam will post applicants' videos on the contest's YouTube channel: DogCloning UK.

Follow us @livescience, Facebook & Google+. Original article on LiveScience.com.

A rush to publish a high-profile study on stem cell cloning appears to have created an embarrassing situation for the journal Cell and the paper's authors.

According to Nature, the paper's lead author Shoukhrat Mitalipov of Oregon Health and Science University admits the buzzed-about paper has three errors, mostly related to image duplication in the manuscript's figures. None of the errors chang the results of the study, Mitalipov said, which were the first-ever stem cells created from cloned human embryos. He and his colleagues plan to share the cloned cells with researchers at 10 other institutions so their legitimacy can be confirmed.

The finding reignited debate about the ethics of human cloning, though researchers say the cloned embryos they created could probably never create a successful pregnancy. The errors have ignited a debate of their own — whether the paper reporting the work was published too quickly. The journal Cell accepted the paper in three days and published it in 12, a mind-blowingly rapid pace in academia, where papers can languish in pre-publication limbo for months or more. In a statement, Cell editor-in-chief Emilie Marcus defended the speedy publication. 

"It is a misrepresentation to equate slow peer review with thoroughness or rigor or to use timely peer review as a justification for sloppiness in manuscript preparation," Marcus wrote. 

To dig into the controversy, read the original thread on PubPeer, the anonymous review site where the errors were first noted. 

Follow Stephanie Pappas on Twitter and Google+. Follow us @livescience, Facebook & Google+.

A new stem cell discovery has reawakened controversy about human cloning — though technical challenges mean scientists are far from being able to create human babies as in Michael Bay's 2005 sci-fi flick "The Island."

Not that they would even want to.

"Nobody in their right mind would want to do that," said John Gearhart, the director of the Institute for Regenerative Medicine at the University of Pennsylvania, who was not involved in the study. And indeed, the research wasn't conducted with the idea of creating cloned mini-me's in mind. Instead, scientists attempting to treat diseases of the cell's powerhouse, the mitochondria, refined the technique, which is the same one used to create the cloned sheep Dolly in 1996. [5 Wild Stem Cell Discoveries]

But the parallels between the animal-cloning procedure and the new human one have triggered concern. The U.S. Conference of Catholic Bishops (USCCB) swiftly issued a statement condemning the research, both on the grounds that embryos were destroyed in the research process and over the concern that the full reproductive cloning of humans is on its way.

"They or others may be close to being able to develop cloned human embryos to the fetal stage and then beyond," said Richard Doerflinger, the associate director of USCCB's Secretariat of Pro-Life Activities.

Technical difficulties

Fortunately for anyone concerned about the specter of human cloning, scientists say they're nowhere close to being able to get cloned human embryos past early stages of development. The study's leader, Shoukhrat Mitalipov of Oregon Health & Science University, told reporters that the early embryos — 100-cell bundles known as blastocysts — seem to have defects preventing them from implanting properly in the uterus and reaching maturity.

A blastocyst consists of an inner mass of cells that will become the fetus. Surrounding this inner cell mass as a hollow ball is a layer of cells called the trophoblast. These trophoblast cells are destined to become the placenta, the organ that nourishes the growing embryo and, later, the fetus. [8 Odd Changes That Happen During Pregnancy]

But in clones, the trophoblast cells frequently fail, perhaps a domino effect from just a few genes going wrong, said Jose Cibelli, a stem cell researcher at Michigan State University. The mother's body may reject the implanting embryo. If implantation occurs, the vast majority of cloned embryos fail to make it past the first trimester of pregnancy.

For example, scientists can take a normal embryo from the uterus of one cow, transplant it into another and have a 60 percent chance of a normal calf being born. Transferring a cloned cow embryo into a cow uterus results in a healthy calf less than 10 percent of the time, Cibelli told LiveScience.

"When you see that scenario, whoever wants to move this into humans quickly, I think it should be criminal," Cibelli said. "We should not do this. It's totally crazy."

So far, Mitalipov and his colleagues have not been able to grow a cloned monkey fetus to term, suggesting that primate reproduction may be even more complex than what is known from Dolly the sheep and other farm animals.

The goal of cloning

So why clone human embryos at all?

The answer is stem cells. These cells have the capability to develop into any tissue in the body — a talent that could make them the stars of regenerative medicine, the goal of which is to grow fresh cells and tissues from patients suffering from various diseases.

Scientists are now able to take regular adult cells and tinker with their genes, turning back time to make these single-use cells pluripotent, or capable of differentiating into multiple cell types. These cells are called induced pluripotent stem cells (iPS cells), and their use is generally supported by anti-abortion groups such as the USCCB, since no embryos are destroyed in their creation.

"We think that it is wrong to attack some innocent human lives here and now to help others down the road," Doerflinger told LiveScience. "Fortunately, the great advances we are seeing in the use of adult and iPS stem cells provide promising alternative ways to heal illnesses without raising people’s temptations to engage in such attacks," he said, referring to the destruction of human embryos.

It's true that iPS cells have great promise. On the other hand, they may have drawbacks. Researchers aren't sure how the human immune system will respond to iPS cells, and there are questions about how stable the revised genomes of these cells would be over time.   

"From the mouse data, we know that [embryonic cloning] is better than iPS cells," Cibelli said.

What's more, iPS cells can't be used to treat diseases of the mitochondria, which are tiny organs within cells that convert the molecules in the food we eat into chemical energy the cell can use. Mitochondria have their own DNA, separate from what's in the nucleus. Trying to treat a mitochondrial disease by turning back the clock on an adult cell's genome would do nothing, because the messed-up mitochondrial DNA remains in the iPS cell.

An embryonic clone is a different story. In this technique, scientists take an unfertilized egg cell and remove the DNA in the nucleus, keeping its mitochondrial DNA intact. They then take an adult skin cell, extract the DNA, and insert it in the place of the egg's original nucleus. Now that adult cell's genome can hum along in its new home, creating stem cells without the mitochondrial defects present in its original form. [How Stem Cell Cloning Works (Infographic)]

"That's neat because in one step, you can technically get rid of that [mitochondrial] mutation," Penn's Gearhart told LiveScience.

The resulting embryonic stem cells could then theoretically be grown into adult cells to replace the ailing person's mutated cells.

Time to talk about cloning?

While cloning is not the goal of the controversial new technique, scientists say it would be naïve to ignore the fact that the new research brings them one step closer to being able to create human clones.

"My feeling is that it's sort of an unintentional step in that direction," said Paul Knoepfler, a stem cell researcher at the University of California Davis School of Medicine.

Refining the technique is naturally helpful to anyone out there who might want to start cloning people, Knoepfler said. Any work of the sort would need Food and Drug Administration approval in the United States — not a given, by any means — but rogue clinics or scientists in less-regulated nations could make attempts, he said.

"There may not be a lot of these people out there, but I think there's enough to worry about it," Knoepfler told LiveScience.

Gearhart said concerns about human cloning are "overwrought," given that the scientific community is empathically not interested in crossing the ethical lines involved.

"Who among us would want to take that risk of bringing someone into this world that would be defective?" Gearhart said.

The time for a conversation about cloning may be nearing, however. The cloning of a monkey or other non-human primate would likely be a "strong signal" that it's time to set some rules around human cloning, Cibelli said. Thirteen states currently have laws on the books prohibiting reproductive cloning.

A worst-case scenario would be a clone showing up on the scene before the legalities are hammered out, Knoepfler said.

"As the technology advances, I think the legal and ethical and political dialogue should also go along with it, so we can face these potential future issues in a proactive kind of way," he said.

Follow Stephanie Pappas on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on LiveScience.com.

In the laboratory, scientists have cloned stem cells from human skin and egg cells. This is significant because the process could eventually be used to produce organs or other parts that are genetically identical to the patient's own, and therefore, pose no risk of rejection when transplanted.

Stem cells are primitive, unspecialized cells. A 5-day-old human embryo, called a blastocyst, contains an inner cell mass composed of about 12 embryonic stem cells.

Adult human bodies contain relatively few stem cells, mostly concentrated in the bone marrow.

Stem cells’ value to researchers is that they can be induced into becoming specific tissue or organ cells. 

The cloning procedure works by combining a patient's body cell with an unfertilized egg cell from a donor.

The patient's skin cell is inserted into the outer membrane of the egg cell and chemically induced to begin developing into a blastocyst.

In the blastocyst, embryonic cells divide, producing a mass of stem cells.

The stem cells can be induced to differentiate into different types of cells as needed (heart, nerve, muscle, etc.). These cells are genetically identical to the patient's own cells (that is, they are cloned).

In the future, the cloned cells could be transplanted into the patient to replace damaged cells.

Watch out, George Lucas, there's a new attack of the clones, and these ones are furry.

Japanese researchers have created a potentially endless line of mice cloned from other cloned mice. They used the same technique that created Dolly the sheep to produce 581 mice from an original donor mouse through 25 rounds of cloning, the scientists report in the March 7 issue of the journal Cell Stem Cell.

"This technique could be very useful for the large-scale production of superior-quality animals, for farming or conservation purposes," study leader Teruhiko Wakayama of the RIKEN Center for Developmental Biology in Kobe, Japan, said in a statement.

The researchers used a cloning technique called somatic cell nuclear transfer, in which a cell nucleus containing one individual's genetic information is inserted into an egg cell whose nucleus has been removed. Dolly the Sheep became the first cloned mammal in 1996 using this technique. Many other animals have been cloned since, but the technique has had a low success rate and attempts to "reclone" animals have often failed.

Genetic abnormalities that can accumulate over consecutive generations of clones may explain these failures, Wakayama said. [That's Odd! The 10 Weirdest Animal Discoveries]

In their study, Wakayama and colleagues grew the cloned cells in a solution containing trichostatin, a compound that interferes with enzymes that make changes to DNA. Using this technique, the cloning process was five times more successful.

The team successfully cloned the mice 25 consecutive times. In other words, they cloned one mouse, then cloned those clones, and so on. A total of 581 healthy mice were made, all of which were fertile and lived a normal life span of about two years. The efficiency of making the cloned cells neither worsened nor improved over the generations.

"This is a very important set of results," geneticist George Church of Harvard Medical School told LiveScience. It's "not just that it's 25 sequential clonings, it's that they found a way to improve things five-fold," Church said. Figuring out what didn't work was equally important, he added.

No abnormalities accumulated in the mice, even after repeated cloning, the researchers found. "Our results show that repeated iterative recloning is possible and suggest that, with adequately efficient techniques, it may be possible to reclone animals indefinitely," the authors wrote in the study.

In 2008, Wakayama's team created clones from the bodies of mice that had been frozen for 16 years. Other researchers have successfully recloned cows, pigs and cats, but not beyond three generations. Scientists have also created stem cells from cloned human embryos, but ethical and scientific barriers to human cloning remain.

Follow Tanya Lewis on Twitter @tanyalewis314. Follow us @livescience, Facebook or Google+. Original article on LiveScience.com.

In a controversial interview that has ignited commentary across the world, a respected Harvard professor of genetics has suggested an "extremely adventurous female human" might someday serve as surrogate mother for a cloned Neanderthal baby.

Besides saying that the cloning of a live Neanderthal baby would be possible in our lifetime, George Church told Der Spiegel magazine that using stem cells to create a Neanderthal could have significant benefits to society. "The first thing you have to do is to sequence the Neanderthal genome, and that has actually been done," Church said.

"The next step would be to chop this genome up into, say, 10,000 chunks and then ... assemble all the chunks in a human stem cell, which would enable you to finally create a Neanderthal clone," Church told Der Spiegel.

Scientists completed the first sequence of the Neanderthal genome in 2010, finding genetic evidence suggesting ancestors of modern humans successfully interbred with Neanderthals, at least occasionally. More recent research has suggested Neanderthal DNA makes up 1 percent to 4 percent of the genomes of modern Eurasians. [The 10 Biggest Mysteries of the First Humans]

The benefits, according to Church, include an increase in genetic diversity. "The one thing that is bad for society is low diversity," Church said. "If you become a monoculture, you are at great risk of perishing. Therefore the recreation of Neanderthals would be mainly a question of societal risk avoidance."

In his book "Regenesis: How Synthetic Biology Will Reinvent Nature and Ourselves" (Basic Books, 2012), Church writes, "If society becomes comfortable with cloning and sees value in true human diversity, then the whole Neanderthal creature itself could be cloned by a surrogate mother chimp — or by an extremely adventurous female human."

Church said in another interview that he isn't advocating for births of Neanderthal babies from human surrogate moms anytime soon, but that people should start discussing the idea today so we're prepared for the future. Even so, other scientists say the idea is not only tangled with ethical issues, but is scientifically impossible for the foreseeable future.

The ethics of human cloning

Not everyone, however, shares Church's interest in cloned Neanderthals, in light of the ethical issues involved.

 "I don't think it's fair to put people ... into a circumstance where they are going to be mocked and possibly feared," bioethicist Bernard E. Rollin of Colorado State University in Fort Collins told the British newspaper The Independent.

It's also possible a Neanderthal baby would lack immunity to contemporary infectious diseases, and therefore might not survive, the Independent reports. Neanderthals, our closest known genetic relatives, died off some 30,000 years ago. Recent research, however, has suggested Neanderthals and other extinct humans such as the Denisovans might have endowed some humans with robust immune systems.

"Setting aside the ethical issues behind creating the lone survivor of an extinct human species, doomed to be a freak under the microscope of celebrity … I have to question Dr. Church's contention that it would really be that easy to clone a Neanderthal," Alex Knapp said in Forbes. [The 9 Freakiest Medical Conditions]

"Other mammals have been cloned. But at a cost — clones often experience a host of health problems," Knapp said. "For example, the first cloned sheep, Dolly, was one of 29 cloned embryos. He was the only one to survive."

Any surrogate mothers chosen to give birth to a Neanderthal clone might also suffer, Knapp said. "The reality is that success would require dozens of women — many of whom would almost certainly go through the trauma of miscarriage and stillbirths that appear to be inevitable when it comes to cloning.

"The ethical implications of just this simple aspect of the process are pretty damning," Knapp told Forbes.

Were Church's comments misinterpreted?

Church's statements in the Der Spiegel interview have been wildly distorted, according to some observers. "There's always a danger in taking one little comment and blowing it out of proportion," John Hawks, associate professor of biological anthropology at the University of Wisconsin–Madison, told LiveScience.

"He's really talking about science fiction," Hawks said of Church's comments, adding that with current technology, the cloning of any long-extinct species is "completely impossible."

"We are a long way from taking DNA information and making a living cell from it," Hawks said. And while the cloning and rebirth of extinct animals and humans sounds fascinating, it's really not a scientific priority. "It seems to capture people's imagination, but it's not on anyone's agenda," Hawks said.

"We can do a lot better science with this than cloning and bringing extinct species back to life," Hawks said. "If we could clone Neanderthals, we could address every genetic disorder humans have," Hawks said, referring to the technology and advancements needed to achieve both of these feats.

Church himself has distanced himself from the media frenzy surrounding his Neanderthal commentary. "The real story here is how these stories have percolated and changed in different ways," Church told the Boston Herald. "I'm sure we'll get it sorted out eventually."

"I'm certainly not advocating it," Church said. "I'm saying, if it is technically possible someday, we need to start talking about it today."

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Cloning may invoke an image of an army of identical cows or sheep churned out factory-style, but in actuality, the process is much more laborious.

The term "cloning" generally applies to a process more technically known as somatic cell nuclear transfer. What that means is that the DNA from the cell of an adult animal (take cows, for example), called the "donor," is extracted from the cell (usually a skin cell taken in a biopsy) and inserted into an egg cell from another cow. The egg cell has had its nucleus removed so that it will read and duplicate the DNA of the donor cell.

The newly created embryo is then zapped with electricity so that it starts multiplying, until it becomes a blastocyst (a small clump of cells that forms after an egg is fertilized), which is then implanted into a surrogate mother. The resulting newborn will be an identical genetic replica to the donor cow.

Cows have been cloned more than other animals because obtaining eggs from the cow is slightly easier than for swine, said geneticist Bill Muir of Purdue University, an author of a 2002 National Academy of Sciences report on the scientific concerns of animal biotechnology.

This process differs from other methods of artificial breeding, such as in vitro fertilization, in that it uses adult cells, instead of embryos.

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Bananas are a staple food around the world. But the humble yellow fruit faces pests and diseases that threaten to wipe it out across the globe, from convenience stores in Iowa to rural markets in Uganda.

In an effort to save bananas from imminent demise, scientists have now sequenced the banana genome for the first time, a challenging feat and a major advance in the field.

The accomplishment opens the way for developing better banana crops that are naturally resilient against parasites and other stresses.

NEWS: Bananas, Highly Inbred, at Risk

“The banana is very important, especially for tropical and subtropical countries,” said Angélique D’Hont, a geneticist at CIRAD, an agricultural research center in Montpelier, France. “Because the future of the banana is in danger, the sequence will help to produce resistant bananas and avoid the utilization of pesticides. It will be much easier now to identify genes which are important.”

Bananas were first domesticated 7,000 years ago in Southeast Asia. As people migrated, and crossed their own plants with other species along the way, bananas gradually became seedless, delicious and totally sterile.

Instead of multiplying through sexual reproduction, which mixes up the gene pool, bananas are cultivated through vegetative propagation, which involves simply cutting off a section of one plant to grow on its own. It’s the same process used to grow several other major African crops, including cassava, sweet potatoes and yams.

As a result, every single Cavendish banana -- the variety that makes up about half of all bananas eaten around the world -- is an exact clone of every other Cavendish banana.

The shape, color and flavor of these popular fruits are predictable and consistent. But parasites and diseases have adapted to the Cavendish, D’Hont said, making it necessary to use large amounts of pesticides to keep banana crops from collapsing -- up to 50 applications a year in some places.

To decipher the banana’s genetic strengths and weaknesses, D’Hont and a large group of colleagues spent two years sequencing a variety of banana called Musa acuminate, which is a simpler relative of the Cavendish.

HOWSTUFFWORKS: Learn All About the Banana

Once they put together the sequence, the researchers report today in the journal Nature, they discovered several genes that may be involved in pest resistance.

Among other findings, the researchers identified genes involved in ripening after the application of ethylene, which is often added to green bananas during transport. The sequence also revealed that the banana duplicated its entire genome three times (making an extra copy of every single gene in its genome) -- including once 100 million years ago and once 60 million years ago

Putting together the sequence took so long because, compared to many other crops, the banana genome is extremely complex. Even though all bananas are clones of each other, the original gene forms that came from mother and father plants remain different from each other -- unlike in seeded crops that tend to become inbred, said Simon Chan, a plant biologist at the University of California, Davis.

What’s more, bananas have three copies of each chromosome, just like other seedless plants. And for many genes, all three copies are different.

The variety of banana used in the new study had just two of each chromosome, making it simpler than the Cavendish. But by finally deciphering its sequence, scientists will be able to move on to our beloved breakfast fruit and compare the differences.

Knowing the genetic sequence of bananas is a major step toward isolating key genes that will eventually lead to a better banana, Chan said. Future varieties may be able to resist both droughts and diseases, while still tasting good and traveling well.

Those developments are especially important in the developing world, where starchy varieties of bananas supply substantial amounts of calories to the human diet, especially in Uganda and other East African countries. There, Chan said, losing the banana crop would be a humanitarian disaster.

“This is a nice example of how these projects can greatly benefit crops that we might not think about as being important in the developed world but are really, really important for food security and human welfare in developing countries,” Chan said.

“It’s like a moral imperative for us to work on these plants and sequence the genomes of more of the species that are significant in those parts of the world.”

This story was provided by Seeker.

The recent death of Lonesome George, the famed Galapagos tortoise believed to be the last representative of his subspecies, has many experts wondering how we should try to save other endangered and at-risk animals.

Cloning is one option. While cloning methods for reptiles are not as advanced as those for mammals, scientists also say they face other incredible obstacles.

PHOTOS: Lonesome George and Other Animals At Risk

“At the most, I could envision one male turtle of this subspecies cloned in future or maybe two males, but where are you going to get a female?” asked Martha Gomez, a senior scientist with the Audubon Nature Institute, which has one of the world’s few “frozen zoos.”

Frozen Zoos stockpile biological materials from a wide variety of rare and critically endangered species. The biological material is usually composed of gametes (sperm and egg cells), embryos, tissue samples, serum and other items. Together, they represent a bank vault of irreplaceable genetic information that can be preserved for possibly hundreds of years or more. In most cases, the materials are stored in holding tanks filled with liquid nitrogen.

Oliver Ryder, director of genetics at the San Diego Zoo, spoke to Discovery News as his team was racing to the Galapagos Islands to help preserve the tissues of Lonesome George. The San Diego Zoo operates one of the other few frozen zoos.

"This is an extremely urgent matter," Ryder said. "We had planned to meet in the Galapagos in two weeks to discuss preservation of the tortoises there. It is a bitter irony that Lonesome George died before we could even finish setting up the plans. It underscores the importance of preserving such animals."

"We are facing some logistical problems now, but we don’t want to look back with 'what if's," he added. "This may be the only chance we'll have to preserve, document and study this tortoise subspecies."

Ryder believes discussions of cloning Lonesome George are premature at this point. Before that takes place, he thinks more must be learned about this particular tortoise’s physiology and reproduction. Studying Lonesome George’s remains may also help to reveal how tortoises often live to advanced ages, information that could one day lead to breakthroughs in extending human lifespans.

For cloning, researchers are focusing more on “species where we have detailed knowledge of their reproductive biology,” Ryder said. That is one reason why cats, dogs and mice were among the first animals to be cloned. Scientists are now working to clone endangered relatives of such animals, in hopes of releasing those individuals into the wild to strengthen natural populations.

Earlier this year, Gomez and her colleagues successfully cloned endangered black-footed cats. An endangered wild ox, called a gaur, and a banteng (wild cattle) have also been successfully cloned. Work is underway to clone and otherwise increase the population of Sumatran rhinos, which presently number only about 200-300 in the wild.

While one healthy clone is an interesting novelty, clones must also be able to reproduce in order to be fully successful. Gomez said that kittens of cloned wild cat parents have died “due to problems with nuclear programing,” but some normal kittens have resulted and continue to thrive.

NEWS: Woolly Mammoth To Be Cloned

Both she and Ryder say that there is no international policy calling for cloning and preservation of highly endangered species. Instead, isolated facilities and the work of dedicated individuals are responsible for the successes.

“The effort needs to be more widespread and organized,” Gomez said.

Through published papers and talks, Ryder and his colleagues have repeatedly called for an organized global effort. It would need an “overarching international body” on par with UNESCO, he believes.

HOWSTUFFWORKS: Cloning

“The first step is saving tissue samples, as we’re in the process of doing for Lonesome George,” he said. “But we who are among the forefront would like to train others to establish frozen zoo biobanks in other countries.”

“I am confident that one day such an international structure will come together, bringing in other conservation work, such as preserving habitat,” Ryder concluded. “It’s poignant to lose a subspecies like that of Lonesome George. People in the future will be looking back at us, wondering why we didn’t act sooner.”

This story was provided by Discovery News.

Ever wanted an identical twin? A clone to do your chores? If you were a coral embryo, you could just break in two and make yourself a body double, new research suggests.

Coral embryos, which are complex marine animals with differentiated cell layers and tissues, are able to reorganize their bodies, even if they've broken in half, to form anew. This means that when even a gentle wave comes along and a coral embryo is damaged, it just ends up turning into two smaller, identical twins.

This ability "helps to explain how coral maximize their chances of finding a suitable habitat in which to settle and survive," study researcher Andrew Heyward, of the Australian Institute of Marine Science, said in a statement. "This is another example of the complexity of these incredible animals and suggests that there may be more to learn about the lives of corals."

Embryonic events

When corals reproduce, they create and release billions of embryos into the oceans around them. These embryos, which form after sperm and egg meet in the water, float to the top, where they are battered by waves and wind as they are carried to new locations, where they grow into juvenile corals.

"As the early-stage embryo develops, it divides into a cluster of cells," Heyward said. "Because this ball of cells lacks a protective outer layer, we wondered whether subjecting them to a little turbulence might cause them [to] break up."

So Heyward and his colleagues simulated in the lab wave conditions on the Great Barrier Reef. They did see the embryos break apart, but what they saw next was unexpected: Rather than dying, the broken parts were able to continue dividing normally to maturity.

Special reproduction

The divided embryos and the resulting juvenile corals were smaller than average, but they were able to settle and grow alongside their full-size siblings in the lab. In the end, being "fragile" is an advantage to the corals — it allows them to create more of themselves, increasing the likelihood that one of the clones will land somewhere hospitable. [Gallery: Peek Inside a Coral Nursery]

"It appears that the lack of protective membrane is no accident," study researcher Andrew Negri, also of the Australian Institute of Marine Science, said in a statement. "Almost half of all these naked embryos fragmented in our experiments, suggesting that this has long been part of the corals' repertoire for maximizing the impact of their reproductive efforts."

What's interesting, on top of the coral embryo making its own identical twin, is that this is a completely new mode of reproduction in the animal kingdom. (Other animals can clone themselves but only if they are already full-grown adults, not embryos.)

This means coral have two ways of reproducing: They can sexually reproduce to create embryos that are genetically different from the parent, and they can also create genetically identical clones from embryos. This reproductive flexibility may help corals survive in the unpredictable ocean environment, the researchers suggest.

You can follow LiveScience staff writer Jennifer Welsh on Twitter @microbelover. Follow LiveScience for the latest in science news and discoveries on Twitter @livescience and on Facebook.

A team of South Korean scientists led by the Hwang Woo-suk – who made headlines in 2005 for falsely claiming to have extracted stem cells from cloned human embryos – has just announced that they have successfully cloned coyotes for the first time. Here are some answers to a few questions you may have about reproductive cloning.

How does reproductive cloning work?

Reproductive cloning usually employs a technique called somatic cell nuclear transfer. Researchers first take a somatic cell (any cell in the body other than a sperm or egg) from the creature they plan to clone, extract the cell's nucleus, which contains the cell's nuclear DNA, and discard the rest. They then remove the nucleus of an egg cell and insert the somatic cell nucleus in its place. Next, they treat the reconstructed egg with chemicals or electricity to stimulate cell division. If the egg divides normally and forms a blastocyst (a small clump of cells that forms after an egg is fertilized), scientists will transfer it into a surrogate mother to develop into a new animal.

Any animal created using this technique is not actually an identical clone of the donor animal – only the clone's nuclear DNA is the same as the donor. A small portion of the clone's genetic information comes from the egg cell's mitochondria, small structures that help make energy the cell.

What have we cloned so far?

In 1952, researchers cloned the first animal, a tadpole, and a decade later scientists cloned the first fish, an Asian carp. But it wasn't until 1996 that scientists cloned the first mammal from an adult somatic cell – the now world-famous Dolly the Sheep.

Since Dolly, scientists have cloned a growing number of mammals, including cows, pigs, cats, dogs and rhesus monkeys. In 2009, researchers even cloned a newly extinct animal, the Pyrenean ibex, though the cloned mammal died a mere seven minutes after birth.

What are the challenges to cloning?

There are a couple of challenges to reproductive cloning. First, somatic cell nuclear transfer has a high rate of failure – only about one or two out of 100 experiments result in a viable clone. With such a low success rate, cloning an animal – and especially mammals, which tend to have long gestation periods – can become an expensive endeavor.

Cloned animals also experience many health complications, such as abnormally large organs, and so they often die early. For example, scientists euthanized Dolly when she was six years old (half her expected lifetime) because she suffered from progressive lung disease and severe arthritis.

Is cloning humans legal in the United States?

There are no laws against cloning animals in the U.S. and there are no federal laws that ban human cloning completely. However, 13 states, including California, Iowa and Massachusetts, have state laws in place that ban reproductive cloning of humans.

Legal issues aside, some major organizations advise against human reproductive cloning on ethical grounds. Because of the low success rate for reproductive cloning and the likely health complications of cloned individuals, physicians from the American Medical Association and scientists with the American Association for the Advancement of Science publicly advised against human reproductive cloning. Additionally, religious groups raise other ethical concerns, such as the idea that reproductive cloning is "playing God." [Report: Ban Cloning or Prepare for Consequences]

Is cloning humans even possible?

Human cloning is not yet possible, but cloning technology is taking small steps in that direction. Much cloning research is actually focused on creating embryonic stem cells from the cloned embryo, rather than growing cloned humans (this field is called therapeutic cloning and is less controversial than reproductive cloning).

Recently, scientists at the New York Stem Cell Foundation Laboratory were able to create a developing cloned embryo, from which they were able to derive a self-reproducing line of embryonic stem cells. However, they did so without first removing the egg cell's, so the embryo was actually abnormal and had an additional set of chromosomes.

This story was provided by Life's Little Mysteries, a sister site to LiveScience.

Michael Jackson reportedly was very interested in being cloned.

"I really want to do it Uri, and I don’t care how much it costs," he is said to have told Uri Geller, a self-proclaimed psychic who claims to bend spoons with his mind (boy, if I had that power I'd sure use it for something besides spoon-bending!).

Whether the news report is accurate or not, the fact is the science didn't advance soon enough for Jackson. There have been no substantiated claims of cloned human embryos grown into fetal stages and beyond, despite rumors to the contrary. The capability to so do is near, however.

Could Jackson have been the first, if someone had tried?

Clones have been made of mice, cows, pigs, dogs, cats, monkeys and of course sheep. The technology has been around longer than you might have thought: A tadpole was cloned in 1952.

But the process remains ineffective. About 98 percent of all cloning experiments don't work, according to a Human Genome Project fact sheet, and many of those that work result in debilitated offspring and premature deaths.

More significant than scientific barriers could be ethical concerns. Physicians from the American Medical Association and scientists with the American Association for the Advancement of Science have issued formal public statements advising against human reproductive cloning, the Genome Project notes.

In 2007, a policy analysis by the United Nations University concluded that cloning should be outlawed or the world must plan to protect clones from abuse and discrimination. Among the concerns: Cloning might turn human life into a commodity, leading to a spare parts market for harvesting human organs from cloned "brain-less bodies" for the rich as they seek to extend their life span.

Jackson, it was reported by The Mirror, "just wanted a mini-version of himself cloned to carry on his legacy."

• More Cloning News

In The Water Cooler, Imaginova's Editorial Director Robert Roy Britt looks at what people are talking about in the world of science and beyond. Find more in the archives and on Twitter.

Japanese scientists cloned mice that had been frozen 16 years and whose cells had burst, according to Reuters. Since the mice were not particularly well preserved, the researchers say their nuclear transfer techniques "could be used to 'resurrect' animals" such as mammoths.

Researchers have been aiming for this breakthrough for years. Parallel efforts in recent years have led to decoding the genetics of the extinct cave bear and a partial decoding of the mammoth genome. "Our discovery means that recreating extinct hybrid animals is theoretically possible," researchers said when that breakthrough came in 2005.

In northern Siberia, researchers are attempting to create Pleistocene Park by restoring a large area of wetlands and forest to the dry landscape that existed more than 10,000 years ago. They are re-introducing herbivores and predators they think will alter the biology and ecology of the region to its previous state.

How far back might resurrection go? Nobody is expecting T. rex to roam the planet again, but tissue from the beast has been recovered.

This article is from the LiveScience Water Cooler: What people are talking about in the world of science and beyond.

If there's something strange in the neighborhood … clone yourself. That's the philosophy of sand dollar larvae, which copy themselves when they sense predators are near.

Scientists exposed 4-day-old sand dollar larvae to fish mucus, a sign that danger is close. They found that the larvae created clones of themselves within 24 hours.

"It’s the first time we've seen anything clone itself in response to cues that predators are near," said researcher Dawn Vaughn, a biology doctoral student at the University of Washington's Friday Harbor Laboratories.

Sand dollar larvae are tiny globs that float along with plankton in the sea, an easy target for hungry fish. When they are 6 weeks old, they settle to the seafloor and eventually become adult sand dollars with their distinctive petal-patterned shells.

After being exposed to fish mucus, the larvae formed embryo-like buds that eventually detached and developed into new, genetically-identical larvae that were much smaller than the originals. The parent larvae were left smaller, too, measuring about half their beginning size.

Larvae that were not exposed to the fish mucus did not clone themselves.

The scientists think cloning may provide a double benefit to larvae facing danger. By doubling themselves, they have a second chance to ensure their genetic information survives even if one larva gets eaten.

Additionally, being smaller may be beneficial to larvae trying to hide from fish.

"Fish are visual predators and often choose their prey based on size," Vaughn told LiveScience. "You're apt to see something bigger. Based on past research, we're hypothesizing that small size protects larvae, but we have to test that."

Even if being tiny helps the larvae, they could suffer for it later as full-grown sand dollars that live on the sea floor. For many species, being bigger helps scare off predators. The researchers don't know yet if this is true for sand dollars.

"We're suggesting that that’s the tradeoff," Vaughn said. "You may reduce your vulnerability as a larva, but when you reach the sea floor, potentially small size ends up hurting you. But if you don't make it to the sea floor in the first place, it might be worth the tradeoff."

Cloning had previously been observed in sand dollar larvae in response to a greater availability of food or favorable temperatures, but never in response to danger.

Vaughn and her colleagues detail the findings in the March 14 issue of the journal Science.

• All About Cloning
• Images: Rich Life Under the Sea
• Image Gallery: Small Sea Monsters

In science fiction, teleportation is not always perfect. Improperly maintained teleporters can result in "poor fidelity" during transmission—and a mess on the floor of the transporter room.

In one celebrated instance, the use of the teleporter even involved creating a copy.

In the Star Trek episode "The Enemy Within," first broadcast in 1966, the transporter aboard the Enterprise malfunctions, creating a copy of Captain Kirk. The copy demonstrates less than 100 percent fidelity, however; it embodies only his most selfish and angry qualities.

The first experimental demonstration of quantum telecloning has just been accomplished by scientists at the University of Tokyo, the Japan Science and Technology Agency and the University of York. Telecloning is a combined achievement; it combines quantum teleportation with quantum cloning into a single step.

In ideal quantum teleportation, the original particle is destroyed and its exact properties are transmitted to a distant particle. In telecloning, the original is destroyed and its properties are sent to two distant particles with an accuracy of less than 100 percent. The Heisenberg principle limits cloning fidelity; researchers would otherwise be able to make enough clones to learn everything about the original particle.

In their telecloning experiment, researchers cloned a beam of laser light, transmitting its electric field amplitude and phase - but not its polarization - to two distant beams with 58 percent fidelity. The theoretical limit on the experiment was 66 percent.

This demonstration may cause problems in another field of application for quantum teleportation. Until now, quantum cryptography had offered a perfectly secure communication standard. Now, however, an enemy within your communication center might arrange to send a copy of the message to a distant eavesdropper.

For more information, see Deterministic Quantum-State Teleportation Achieved With High Fidelity and Quantum Dot Switches.

Read the Physics News update and press release on telecloning.

(This Science Fiction in the News story used with permission from Technovelgy.com - where science meets fiction.)