Scientists have described a new species of highly venomous box jellyfish based on specimens that were lurking near a Singaporean island formerly known as Pulau Blakang Mati, or the "Island of Death Behind," in 2020 and 2021.

The newly described species, Chironex blakangmati, was named after the island's original, ominous name in Malay, rather than its name since 1972, Sentosa, which means "peace and tranquility." That's fitting, given how dangerous the animal is.

C. blakangmati is one of four known species of Chironex box jellyfish, all of which are incredibly venomous. Their stings, delivered via special cells on their tentacles called nematocysts, are so powerful they can kill humans. And unlike most other jellyfish that simply ride on currents, Chironex box jellies can actively identify and swim toward prey thanks to their strong musculature and complex eyes.

Previously, scientists had mistaken C. blakangmati for another box jellyfish species, C. yamaguchii. However, it turns out that these box jellies are different, both genetically and morphologically, scientists reported in a new study, published May 15 in the journal Raffles Bulletin of Zoology.

"C. blakangmati looks remarkably like Chironex yamaguchii — a jellyfish species I first discovered in Okinawa while doing my master's degree there," study co-author Cheryl Ames, a professor of applied marine biology at Tohoku University in Japan and a research associate at the Smithsonian National Museum of Natural History in Washington, D.C., said in a statement. "But we realized they were completely distinct. I actually went back to dust off an old sample of C. yamaguchii I still had in storage in Okinawa to help with the comparisons!"

The researchers found that the newly identified species lacks branched canal structures at the bottom of its bell-shaped body that C. yamaguchii and the other two Chironex species, C. fleckeri and C. indrasaksajiae, exhibit. Specifically, these canals sit within the perradial lappets, which are flaps reinforcing the musculature that propels box jellyfish when they swim. Together with genetic discrepancies, this anatomical difference confirmed that C. blakangmati is a separate species, according to the statement.

"Our thorough review and analysis of all the Chironex species known to date reveal a lot about these box jellyfishes," study co-author Danwei Huang, an associate professor in the National University of Singapore's Department of Biological Sciences and the Lee Kong Chian Natural History Museum, said in the statement.

The results also revealed for the first time that C. indrasaksajiae, which is typically found off the coast of Thailand, is present in Singapore's waters. Nicknamed the Thai sea wasp, this species can be deadly.

"We were surprised to find C. indrasaksajiae so far away from Thailand," Ames said. "Recording range expansions like these is really important, as we currently know so little about the biodiversity and spatial distribution of box jellyfish."

A better understanding of the distribution of box jellies could help prevent severe injuries and deaths in humans, according to the statement.

Records suggest box jellyfish stings cause around 40 deaths per year globally, but some experts think that number is a huge underestimate.

A years-long mystery about a shiny blob found at the bottom of the ocean has finally been solved.

When the strange golden orb was discovered on a deep-sea dive in Alaska waters in 2023, marine biologists were stumped. The National Oceanic and Atmospheric Administration's Seascape Alaska 5 expedition came across the smooth, soft object stuck tightly to a rock about 2 miles (3.2 kilometers) below the surface of the Pacific Ocean. Using a suction attachment, the remotely operated vehicle brought the object to the surface for further study on the ship waiting above, the Okeanos Explorer. But even upon closer examination, they couldn't identify it.

There were many theories about what it could be. Perhaps it was an egg, a sponge or a mat of microbes.

"Everyone was like, 'What the heck? What is that?,'" Allen Collins, a zoologist at the Smithsonian National Museum of Natural History in Washington, D.C., told Live Science.

Now, he's led an analysis that has finally revealed what the orb is ‪—‬ and it turns out that it's something secreted by a mysterious deep-sea creature called Relicanthus daphneae.

"The first thing we were looking for was gross anatomy," he said. "Is there a mouth somewhere? Can we find muscles? The sort of thing that would tell us that it's some particular kind of an animal. And we didn't find any of that.”

The next step was to put it under a microscope. This inspection revealed that the tissue contained nematocysts ‪—‬ the stinging cells that define the Cnidaria phylum, which includes more than 11,000 species of aquatic invertebrates, such as jellyfish, hydroids, sea anemones and corals.

These stinging cells were spirocysts, which Collins said are unique to the Hexacorallia class. That cut it down to 4,000 or so species.

Next, the team tried genetic tests and detected DNA from lots of microbes, as well as from an anemone-like organism ‪—‬ R. daphneae.

This is when co-author Estefanía Rodríguez, curator of marine invertebrates at the American Museum of Natural History in New York, who had been studying R. daphneae specimens for many years, got involved. She recognized the tissue as a cuticle, which means the golden orb is the structure that an anemone secretes beneath it to cement itself to rock. The work is posted on the bioRxiv preprint server and hasn't been peer-reviewed yet.

"It is wonderful that the authors were able to gather enough evidence from the sample to identify it, even though it was actually a remnant not a whole specimen," Tammy Horton, a deep-sea taxonomist at the National Oceanography Centre in Southampton, U.K., told Live Science in an email.

She said the work demonstrates the importance of both DNA identification and obtaining specimens, because physical samples are needed to confirm the identity of little-known marine species.

"It's great to have an answer to what the 'golden orb' is, and as is often the case in the deep sea, it's a surprise," said Jon Copley, a marine ecologist at the University of Southampton in the U.K. "From its looks alone, we didn't guess it would be the remnants of an anemone-like animal."

Scientists haven't agreed on which group R. daphneae fits into yet. Genetic data from a 2019 study indicates it doesn't sit in current taxonomic groups and is in a sister group to true anemones, so it should be called "anemone-like," Copley said.

However, Rodríguez, who was part of the 2019 study's team, is still convinced it is an anemone, she told Live Science. "Morphologically it is an anemone, and I do believe it's an anemone," Rodríguez said. "We just don't have enough samples to show that yet." She suspects it might be from an ancient line of anemones, which is why it is hard to place.

Regardless of which group it fits into, R. daphneae probably secretes a cuticle to attach to rock but can detach from it to move to a better location and then attach in the new place by creating a new cuticle, Collins explained. That is why the golden orb was left there.

"In some videos, you can see cuticle on the rock adjacent to where the anemone is," he said, adding that in one case, you can spot a long trail along a rock where the anemone appears to have repeatedly started secreting a cuticle before moving on.

R. daphneae has mainly been seen near hydrothermal vents in the Pacific, Southern and Indian oceans, but that may be because scientists visit vents more often than other deep-ocean habitats, Copley said. He suspects the bizarre creatures may be more widespread, and now that we know they leave behind golden orbs, we may get a better idea of how far they spread.

A robot posing as a tough male crab recently challenged real crabs to a showdown during mating season — and the videos are hilarious.

The robot, nicknamed "Wavy Dave," infiltrated fiddler crab (Afruca tangeri) communities on the mudflats of southern Portugal and participated in claw-waving contests, during which males wave one oversized claw to attract females. However, Wavy Dave's mission had problems from the get-go, a new study revealed.

"The females realised he was a bit odd, and some of the males tried to fight him," study first author Joe Wilde, a statistician and modeler in ecology and environmental science at Biomathematics and Statistics Scotland, said in a statement. "One male broke Wavy Dave by pulling off his claw. We had to abandon that trial and reboot the robot."

Claw waving is an important part of fiddler crab reproduction. If a male successfully attracts a female during these displays, then the female enters the male's burrow and allows him to fertilize her eggs, so the stakes are high.

Despite the claw-breaking incident, Wavy Dave proved to be enough of a contender that researchers gained insight into how male crabs respond to rivals. The researchers published their findings Wednesday (Aug. 6) in the journal Proceedings of the Royal Society B Biological Sciences.

Related: Watch this cute robot elephant go bowling — it's the first 3D-printed robot of its kind

Scientists already knew that many animals change and adapt their display behaviors based on the presence and proximity of their rivals. However, less is known about how animals respond to changes in their rivals' signaling behavior, according to the study.

Wilde used a 3D printer to create a model of a fiddler crab, and then built Wavy Dave's claw-waving mechanism. The robot crab had two interchangeable claw options for its display — one average length and one large — and was controlled from a mobile app using Bluetooth.

The researchers put their robot to the test on the crab-filled mudflats of Ria Formosa Natural Park. Female fiddler crabs typically select males who have larger claws and who wave their claws quickly, according to the statement. When Wavy Dave was around, the researchers found that rival males waved for longer but not faster. In the study, the researchers speculated that the males assumed a female was present because of Wavy Dave, but they waited to actually see the female before going all out with their own display.

The team also found that males were less likely to retreat into their burrows when the robot crab was waving, particularly when Wavy Dave's claw was smaller than theirs and thus potentially less attractive to a female. Furthermore, the real crabs were less likely to compete if their robot rival had a larger claw, potentially sensing the contest was a lost cause or were wary of being attacked, according to the study.

The study's findings suggested that male crabs change their behavior in response to what their rivals are doing, investing more energy when they've got a greater chance of success.

"If you own a shop and your rivals start selling things really cheaply, you might have to change how you run your business," Wilde said. "The same might be true for males signalling to attract females — and our study suggests males do indeed respond to competition. Our findings reveal the subtle ways in which these crabs adjust their behaviour to compete in a dynamic environment, investing more in signalling when it is likely to be most profitable."

A mysterious oceanic barrier is stopping some deep-sea jellyfish in the Arctic from reaching the Atlantic Ocean, a new study has found.

The animals, members of the jellyfish subspecies Botrynema brucei ellinorae, inhabit depths between 3,300 and 6,600 feet (1,000 to 2,000 meters) and can be divided into two groups based on whether individual specimens have a knob on their umbrella-like bell structure.

"This jellyfish [...] has two different shapes depending on which area it occurs in — one with a distinctive knob at the top and one without," study lead author Javier Montenegro, a biologist at the University of Western Australia, said in a statement.

The sea creature’s anatomy somehow influences its worldwide distribution: jellyfish with the distinctive knob live across all oceans and latitudes, while those without a knob have only ever been documented in the Arctic and sub-Arctic, Montenegro said.

For the study, Montenegro and his colleagues examined observational and photographic records of B. brucei ellinorae going back more than 120 years. The researchers then mapped the distribution of the jellyfish subspecies by combining these records with genetic analyses. They published their results in the online version of the journal Deep Sea Research on July 3.

Related: Jellyfish Lake: Palau's saltwater pool with a toxic bottom and surface waters brimming with millions of jellyfish

Genetic data indicated that specimens of B. brucei ellinorae with and without knobs in the Arctic and sub-Arctic were almost identical to specimens with knobs in the western Atlantic. This suggested that, despite strong genetic similarities, knobless jellyfish were unable to leave the frigid waters.

So how does the animal’s shape determine its distribution? It appears that access to the Atlantic is blocked by a barrier — not a physical obstacle, but a biological one, or one determined by local geography.

"The differences in shape, despite strong genetic similarities across specimens, above and below 47 degrees north, hint at the existence of an unknown deep-sea bio-geographic barrier in the Atlantic Ocean," Montenegro said.

This barrier is located within the North Atlantic Drift, a warm ocean current that extends northward from the Gulf Stream, but it's unclear if the current itself is the obstacle for knobless jellyfish. A possible explanation could be that there are predators lurking beyond the North Atlantic Drift that knobless jellies aren't equipped to escape — but why having a knob may be advantageous remains unclear.

The barrier "could keep specimens without a knob confined to the north while allowing the free transit of specimens with a knob further south," Montenegro said.

No such barrier is required to keep knobless B. brucei ellinorae in Arctic waters on the Pacific Ocean side, because the Bering Strait already blocks most deep-sea creatures from moving south, according to the study. The strait is only 165 feet (50 m) deep, so deep-sea jellyfish like B. brucei ellinorae can't cross it.

The discovery of a potential oceanic barrier associated with the North Atlantic Drift is important, as it could help scientists better understand evolutionary relationships and dispersal patterns. "The presence of two specimens with distinctive shapes within a single genetic lineage highlights the need to study more about the biodiversity of gelatinous marine animals," Montenegro said.

Rubbery blue sea creatures are washing up on California beaches by the thousands.

The translucent blobs, known as by-the-wind sailors (Velella velella), began piling up Sunday (March 30) along several beaches in the San Francisco Bay Area. Although the animals look like jellyfish, they're more closely related to the Portuguese man o' war (Physalia physalis).

Each creature, which can grow up to 4 inches (10 centimeters) long, is actually a colony of hundreds of smaller organisms with specialized functions. The velellas' S-shaped sails crest the surface of the ocean, carrying them through the warm waters they call home, while their short tentacles hang below the water to catch their prey.

By-the-wind sailors' stings are relatively mild compared with those of their more dangerous cousins, though experts recommend that you avoid touching your face or eyes after coming into contact with one.

Related: The weirdest creatures to wash ashore

These blobs have turned up en masse on beaches around the world before, usually in the spring and early summer. The creatures typically live in the open ocean, but large storms blowing in over the coast can propel them onto shore.

"This time of year the ocean along the west coast transitions into upwelling season," Jennifer Stock, an education specialist at Greater Farallones National Marine Sanctuary in California, told SFGate. Upwelling occurs when cold, nutrient-rich water rises from deep in the ocean.

"The true start/end of that season shifts every year based on a wide set of variables, but the presence of velellas indicates a shift in winds and currents, and the velellas, which are propelled by wind/current alone, get directed to the beaches," Stock said.

Because the velellas can't steer themselves, they get stranded on the beach until either the tide carries them back out to sea or they die. Recent northward winds and storms have carried the animals to the Bay Area over the past week — and experts predict more could wash up in the coming days.

"I would say if we get a nice high pressure system, which is generally associated with nice clear skies, but also upwelling, it's going to really concentrate them just offshore," Raphael Kudela, an oceanographer at the University of California, Santa Cruz, told KQED. "And then all we need is a break in that — a low [pressure system] coming through or the high weakening — and then we would probably see a nice big raft of them come washing into the beaches."

"It's kind of cool to see," Kudela added. "They're really beautiful."

A gigantic iceberg that broke off of an Antarctic glacier has revealed a thriving never-before-seen ecosystem in the depths beneath.

The iceberg A-84, which is roughly the size of Chicago, calved from Antarctica's George VI Ice Shelf on Jan. 13, 2025.

After receiving news of the iceberg’s movement from satellite imagery, scientists aboard the Schmidt Ocean Institute's research vessel Falkor quickly hurried to the site. Just 12 days later, they arrived to find a never-before-seen ecosystem filled with giant sponges, fish, enormous sea spiders and octopuses exposed to the open air for the first time.

"We seized upon the moment, changed our expedition plan, and went for it so we could look at what was happening in the depths below," expedition co-chief scientist Patricia Esquete, a marine biologist at the University of Aveiro in Portugal, said in a statement. "We didn't expect to find such a beautiful, thriving ecosystem. Based on the size of the animals, the communities we observed have been there for decades, maybe even hundreds of years."

What lies beneath Antarctica's roughly 500 feet (150 meters) of ice is scarcely known, but scientists have suspected that it is filled with a gigantic network of rivers, lakes and estuaries. Yet it wasn't until very recently that scientists discovered that this hidden underworld harbored life.

Related: Scientists create new map showing ice-free Antarctica in more detail than ever before

Without sunlight or nutrients raining down from above, this life is likely sustained by deep-sea ocean currents that slip beneath the surface of the shelf, although scientists are unsure if this is the only mechanism at play.

To investigate the once-hidden biome, the scientists deployed a remotely operated submarine (named SuBastian), which — due to the thick ice blocking off GPS signals — navigated using sound waves to arrive at the ocean floor.

Once there, the submarine collected biological and geological samples from among the region's coral and sea sponges. Some of these creatures' enormous sizes suggested they'd been growing for centuries. The researchers also deployed other autonomous vehicles to study how meltwater is affecting the region.

"The science team was originally in this remote region to study the seafloor and ecosystem at the interface between ice and sea," Jyotika Virmani, executive director of the Schmidt Ocean Institute, said in the statement. "Being right there when this iceberg calved from the ice shelf presented a rare scientific opportunity. Serendipitous moments are part of the excitement of research at sea — they offer the chance to be the first to witness the untouched beauty of our world."

Antarctica quiz: Test your knowledge on Earth's frozen continent

An octopus has been spotted catching a ride from an unlikely marine friend: a superfast shark.

Researchers captured a video showing the orange-hued octopus clinging to the back of a large shortfin mako shark (Isurus oxyrinchus) as it swims.

This "sharktopus" was spotted in the Hauraki Gulf off the northern coast of New Zealand's North Island during a December 2023 research trip.

"A large metallic grey dorsal fin signalled a big shark, a short-fin mako. But wait, what was that orange patch on its head? A buoy? An injury?" Rochelle Constantine, a marine biology professor at the University of Auckland who was on the research trip, wrote in a statement. "We launched the drone, put the GoPro in the water and saw something unforgettable: an octopus perched atop the shark's head, clinging on with its tentacles."

The researchers were bemused by this bizarre sight, as octopuses usually live on the ocean floor, while shortfin makos spend most of their time swimming near the surface.

"We really don't know how this octopus, that lives on the seabed, came across this 3 m [meters, or 10 feet] mako shark that lives in pelagic — open ocean waters. It really is a mystery — but the ocean is filled with unexpected things," Constantine told Live Science in an email.

Related: Searching for 'Makozilla' — the supersized mako sharks in the North Pacific

Shortfin mako sharks are the fastest shark species in the world, reaching top speeds of up to 46 mph (74 km/h). They can grow as long as 12 feet (3.7 m) and weigh as much as 1,200 pounds (545 kilograms). These sharks are known for their incredible jumping ability, being able to leap up to 20 feet (6 m) out of the water. They usually hunt near the ocean surface but have been spotted as deep as 1,640 feet (500 m). Their diet mostly consists of other fast-swimming fish such as swordfish and tuna, as well as squid and occasionally other sharks.

The researchers watched the strange "sharktopus" for 10 minutes before leaving the odd companions to continue their journey.

"The shark may not be bothered by the octopus — it certainly didn't appear to be bothered as it swam along slowly," Constantine said. "The octopus was keeping all of its tentacles together on the shark's head, perhaps to avoid being seen but it could stay there while the shark was swimming slowly. I suspect the octopus would have dislodged if the shark swam faster."

Shortfin mako sharks are listed as endangered on the IUCN Red List, largely due to their fins being highly prized in the shark fin trade. They also get caught accidentally as bycatch in tuna and swordfish fisheries, especially with longline fishing gear. Their slow rate of reproduction means that they can't reproduce fast enough to keep up with fishing pressure, leading to population declines.

"One of the best things about being a marine scientist is that you never know what you might see next in the sea. By supporting conservation initiatives, we can help to ensure that such extraordinary moments keep happening," Constantine said in the statement.

Shark quiz: How much do you know about these iconic ocean superstars?

Mantis shrimps pack a powerful punch — and scientists have finally figured out how this super-strong strike doesn't obliterate the shrimps themselves as they lash out. Turns out, these shrimp have a special shock-absorbing "shield" to help them survive as they deliver shell-crushing blows.

The punch of a peacock mantis shrimp (Odontodactylus scyllarus) is the strongest self-powered strike by an animal. They use hammer-like fists, or dactyl clubs, to shatter prey's shells. The strike is so strong it can even break aquarium glass, delivering a force comparable to a .22 caliber bullet.

But because these high-impact strikes generate a lot of force, scientists have puzzled over how the critters can withstand the intense shock waves generated by their own attack.

In a new study published Feb. 6 in the journal Science, researchers examined the structure of the shrimps' clubs. Their findings revealed that the microstructure of these clubs act as natural shock absorbers to limit damage.

"We found it uses phononic mechanisms — structures that selectively filter stress waves," study co-author Horacio Dante Espinosa, a professor of mechanical engineering and biomedical engineering at Northwestern University, said in a statement. "This enables the shrimp to preserve its striking ability over multiple impacts and prevent soft tissue damage."

Powerful punch

Peacock mantis shrimp use a complex system of biological latches and springs in their dactyl clubs to unleash a punch at a speed of 75 feet per second (23 meters per second), according to a 2004 study — 50 times faster than the blink of an eye.

While this immense speed helps deliver a powerful blow, it also creates dangerous shock waves.

"The strike is so fast that it creates cavitation bubbles, which, upon collapsing, generate additional shockwaves, effectively delivering a double impact," Espinosa said.

Previous research theorized that the microstructure of the dactyl clubs helps protect the shrimps from these shock waves.

In the new study, the scientists tested this theory using advanced laser-based techniques to analyze how different wavelengths move through the peacock mantis shrimp's dactyl clubs.

The findings revealed two important regions in these clubs that help them survive their own strikes: the impact region and the periodic region.

The impact region is composed of a layer of chitin fibers arranged in a herringbone pattern that reinforces the club against fractures.

Beneath this layer is the periodic region, made from twisted arrangements of layered chitin fibers. This type of helicoidal structure is known as a Bouligand structure and is found in fish scales and lobster exoskeletons to provide strength and fracture toughness.

The laser tests measured the speed of acoustic stress waves through both regions. These waves passed through the impact region unchanged but moved at varying speeds through the periodic region — suggesting the latter region causes high-frequency waves to disperse to reduce the intensity.

The researchers also discovered that the periodic region filtered out high-frequency shock waves — which can cause significant damage to tissues, according to the statement.

The high-frequency waves were likely generated when the cavitation bubbles collapsed.

"We connected this high frequency to the frequency generated by bubble collapse during the impact event," Epinosa said.

The bundles of fibers in the periodic region act like a "phononic shield," actively blocking, redirecting and scattering waves, and ultimately preventing any harmful shock waves from traveling efficiently through the layer. This protects the delicate tissues of the mantis shrimp from the resulting shock waves of the cavitation bubble.

"The research provided experimental evidence that the Bouligand structure of the mantis shrimp's dactyl club functions as a phononic shield, selectively filtering high-frequency shear waves generated during impact," Espinosa said.

"These features help protect the mantis shrimp's club from damage by mitigating high-frequency stress waves, making it a naturally optimized impact-resistant structure," Epinosa said.

According to the press release, this study could be applied to the development of sound-filtering materials for protective gear and inspire new approaches to reduce blast-related injuries in the military and high-impact sports.

Name: Giant phantom jelly (Stygiomedusa gigantea)

Where it lives: Every ocean except the Arctic Ocean

What it eats: Plankton and small fish

Why it's awesome: Earth's oceans are home to many secretive and unusual creatures that humans rarely see — including giant phantom jellies. These elusive deep-sea creatures have a 3.3-foot-wide (1 meter) bell and four ribbon-like arms that grow up to 33 feet (10 m) long, making them among the largest invertebrate predators in the ocean.

The first giant phantom jelly specimen was collected in 1899 and described in 1910. The species has only been spotted around 120 times since. This is because these jellies generally live in deep waters, down as far as 22,000 feet (6,700 m) below the surface.

They have compressible, squashable bodies, which help them to survive the incredibly high pressures they experience at these depths.

In 2022, researchers observed giant phantom jellies on three separate occasions during submersible expeditions in Antarctica, with videos and images showing the creatures swimming at relatively shallow depths of between 260 and 920 feet (80 to 280 m). In a study reporting the sightings, researchers said it's likely the jellies live closer to the surface in high southern latitudes because seasonal variations in sunlight may drive prey closer to the surface.

Unlike other jellyfish, giant phantom jellies don't have stinging tentacles to catch prey. Instead, they wrap their arms around their food — usually plankton or small fish — and hoist them into their mouths.

Related: Newly discovered jellyfish is a 24-eyed weirdo related to the world's most venomous marine creature

Giant phantom jellies also differ from other jellyfish by being viviparous, meaning they give birth to live young. The young develop inside the mother before detaching from inside the hood and swimming out of their mother's mouth.

When there is visible light, giant phantom jellies emit a slight orange-red light via bioluminescence — meaning they produce light through natural chemical reactions. It's not known exactly why they glow, but researchers believe it could be to communicate, confuse predators, lure prey or attract potential mates. However, because these jellies live in the deep ocean — where red light cannot penetrate very far — their glow is very faint, which likely helps to keep them hidden.

These jellyfish are solo explorers, but they also appear to help to protect smaller sea creatures. During an expedition in the Gulf of California, researchers from the Monterey Bay Aquarium Research Institute spotted small fish, pelagic brotula (Thalassobathia pelagica) sheltering underneath a giant phantom jelly. In return, the fish aided the jelly by removing parasites.

Scientists have discovered a never-before-seen giant sea bug after studying samples purchased from fishers in Vietnam.

Bathynomus vaderi belongs to the genus Bathynomus — giant isopods that are abundant in cold, deep waters. It is a "supergiant," weighing over 2.2 pounds (1 kilogram) and growing up to 12.8 inches (32.5 centimeters) long, making it one of the largest known isopods.

The species is named "vaderi" because its head resembles Darth Vader's iconic helmet from "Star Wars."

B. vaderi has so far only been found near the Spratly Islands, an archipelago in the South China Sea, but it may also live in other parts of the South China Sea, according to the study.

Related: Large, ghostly white crab-like predator discovered at the bottom of the Atacama Trench

For the new study, published Jan. 15 in the journal ZooKeys, the team examined samples caught by local fishers and found that a few specimens had distinctive physical features that marked them as a newfound species. The team described B. vaderi’s pronounced depression in its hip bone and a unique bony ridge protruding from its coracoid bone that distinguishes it from other supergiant isopods.

The researchers noted that Bathynomus species have recently become a delicacy in Vietnam, often compared to lobster. The local demand has turned these sea bugs into an expensive staple of the live-seafood market, leading to increased fishing pressures in the region.

This commercial interest provides both opportunities and challenges, the researchers said. The rapidly growing market could threaten giant isopods, but it could also pave the way for stricter regulations and sustainable practices in deep-sea fishing.

B. vaderi is not the largest isopod species. That title goes to B. jamesi, which can grow to around 20 inches (50 cm) and weigh 5.7 pounds (2.6 kg). Supergiant isopods are often found in deep-sea environments so they are challenging to study due to their inaccessibility.

Crabs are often boiled alive prior to being eaten. The logic has been that crabs do not feel pain because they lack the brain regions responsible for processing pain.

But is that the case — or can crabs feel pain?

Shore crabs (Carcinus maenas) may be able to, according to an October study in the journal Biology. Researchers found these crabs have nociceptors, nerve endings that detect damage to the body and send a pain signal to the brain.

The researchers tested 20 crabs' responses to painful stimuli, like pokes from a plastic instrument or small amounts of vinegar applied to their eyes, antennae, and soft tissue between claws and at joints . Electrodes measured their central nervous system responses, and the scientists saw they were consistent with nociceptive responses. This was not the case when researchers applied non-painful substances such as seawater.

Nociceptors, which humans and many other mammals also have, are activated when the body is injured or threatened with injury. They communicate to the brain, through the feeling of pain, that the body is facing a possible threat, so the animal can respond accordingly.

The existence of nociceptors alone does not necessarily mean an animal feels pain, said study co-author Eleftherios Kasiouras, a biologist at the University of Gothenburg in Sweden. Nociceptors can trigger a pain reflex — like the instinctual removal of a hand from a hot stove. But humans experience the feeling of pain in our brain. So while nociceptors alone don't prove crabs feel pain, they're one piece of the puzzle.

Another study strongly suggesting crabs feel pain

Kasiouras told Live Science that he was not surprised to find pain receptors in crabs: Previous research has found lobsters and crabs respond behaviorally to pain. The combination of these behavioral responses with the central nervous system response makes it more likely that an animal feels pain.

One way scientists gauge if an animal feels pain is through a checklist of criteria that includes whether the animal has nociceptors, pain-related brain regions, interconnections between these receptors and brain regions, responses to anaesthetics and self-protective behaviors in response to injury or threat of injury.

Research on hermit crabs suggests these animals exhibit self-protective behaviors in response to injury. Hermit crabs will abandon their shells to avoid electric shocks, according to a 2016 study published in the journal Behavioural Processes. They are less likely to do so if the odor of a predator is present, suggesting there is a conscious trade-off between avoiding pain and avoiding predators. This adds weight to the idea that hermit crabs experience pain (rather than them fleeing their shells as a reflex).

The new study in shore crabs fulfills another criterion, strongly suggesting crabs can feel pain.

Given the evidence, scientists working in this field are calling for bans on boiling crabs and lobsters alive, calling it an inhumane practice. A ban has been discussed and tabled in the U.K., but bans are already in place in Switzerland, Norway and New Zealand.

Scientists are also looking at whether squids, clams and mussels meet the criteria for feeling pain, but results are varied: They do have nociceptors, and some show pain avoidance behavior, but scientists don't yet understand their brains as well as those of mammals.

"We humans use animals for food, for laboratory research, and many other products," said Kasiouras. "If they experience pain… we need to establish legislation on how to humanely treat them throughout their lives without suffering and minimize their pain."

A ghostly white, unusually large predator has been discovered deep inside one of Earth's deepest ocean trenches.

Found at a staggering depth of 25,900 feet (7,902 meters) in the eastern Pacific Ocean's Atacama Trench, researchers have discovered a new species of large predatory amphipod, Dulcibella camanchaca.

This shrimp-like crustacean, which is 1.57 inches (4 centimeters) long — a giant among amphipods — has specialized appendages to hunt smaller prey lurking at the same depths.

The creature's discovery — details of which were published Nov. 27 in the journal Systematics and Biodiversity — represents the first known large, active predator of its kind in one of the world's deepest oceanic habitats.

D. camanchaca was recovered by scientists from the Woods Hole Oceanographic Institution (WHOI) and Chine's Instituto Milenio de Oceanografía (IMO) during the 2023 Integrated Deep-Ocean Observing System (IDOOS) Expedition, which aims to explore and understand the tectonic and oceanographic processes of the region through multiple deep sea observations over 5 years.

"Dulcibella camanchaca is a fast-swimming predator that we named after 'darkness' in the languages of the peoples from the Andes region to signify the deep, dark ocean from where it predates," study co-lead author Johanna Weston, a hadal ecologist at WHOI, said in a statement.

The hadal zone describes the deepest region of the ocean, describing everything under 19,680 feet (6,000 metres below the surface.

The name "Dulcibella" pays homage to Dulcinea del Toboso, the protagonist's unrequited love interest and muse in the Spanish novel "Don Quixote".

Related: Why do animals keep evolving into crabs?

The Atacama Trench is one of the deepest on Earth, reaching about 26,460 feet (8,065 meters) below sea level. It stretches approximately 3,666 miles (5,900 km) in length, running parallel to the coasts of Peru and Chile.

During the IDOOS exhibition, the specimens were collected with a special lander vehicle that carries scientific equipment, including baited traps, to and from the surface.

Four individual specimens of the newly discovered species were collected, frozen, and later analysed genetically. DNA analysis revealed this tiny predator is not only a new species, but also a new genus (the taxonomic classification above species).

The discovery highlights the biodiversity in this extreme environment, which is characterized by intense pressure and darkness. The Atacama Trench sits beneath nutrient rich surface waters, and is far removed from other hadal environments, according to the statement. This means it has a wide variety of native species.

"More discoveries are expected as we continue to study the Atacama Trench," Carolina González, a researcher with the IMO and co-lead author of the study, said in the statement. Exploration may reveal more species, as well as a deeper understanding of how these enigmatic ecosystems respond to man-made threats, such as pollution and climate change.

First-of-its-kind footage captures the moment an octopus fires projectiles at predatory fish while hiding in a clam shell, like a mini sharpshooter.

The clip, filmed for Netflix's new series "Our Oceans," shows a coconut octopus (Amphioctopus marginatus), also known as a veined octopus, as it fires tiny stones from its siphon — a tube-like structure octopuses use to swim and steer — at fish swimming by.

"We couldn't believe it," Katy Moorhead, assistant producer and field director for the series, told Live Science in an email. "She was shooting fish, with stones, through her siphon! We were so surprised. Nobody had ever recorded veined octopuses using their siphons as weapons before."

The team filmed the clip around 30 feet (9 meters) below the ocean surface in Southeast Asia. The filmmakers were initially looking at the impact of plastic pollution on the ocean, filming a lone octopus living in a trash-filled seabed. But when they reviewed the footage, they realized they'd captured a completely new behavior.

Related: Octopuses burn more calories changing color than you use on a 25-minute run

The team returned to the octopus to find out if this was a one-off event, or if the octopus had worked out how to use its siphon as a pea-shooter to deter predators. Roger Munns, the director of photography, spent 110 hours with the octopus over three weeks, eventually capturing the behavior in detail — showing how she gathered rocks and debris, loaded it, then fired the projectiles out. "She turns her siphon into a gun," former President Barack Obama, who narrates the series, said in the show.

The stones were fired out so fast it could only be seen on the footage in slow motion.

"Faced with a large fish who was giving away the location of her clam hideout, the octopus fired a stone out of its breathing siphon, and hit the fish square on the face," executive producer James Honeyborne told Live Science in an email.

Coconut octopuses tend to live in sandy, muddy habitats in shallow waters. They're found throughout the Indian Ocean and emerge from their hiding places at dawn and dusk to forage. They're known for building armor from clam and coconut shells, pulling the halves together to create shields. When not in use, they carry these shells around with them — stacking them up, sitting inside the shells, then sticking their arms out to move along the seafloor.

The newly recorded shooting behavior is now being analyzed to better understand how and why these octopuses do it. "The fish were clearly startled and did then leave the vicinity of the octopus, suggesting it is an effective deterrent," series producer Jonathan Smith told Live Science in an email. "A scientist is now analyzing this surprising footage to get more answers."

"Our Oceans" is available to stream on Netflix.

For octopuses, changing color burns about as many calories as a human on a 30 minute jog pound for pound, new research suggests.

Octopuses are masters of disguise, changing color at the drop of a hat to startle predators and hide from prey. But the energetic cost of this shade shifting has remained a mystery.

Now, for the first time, biologists have measured how much energy these animals actually use for their total tonal transformations. The finding can tell scientists more about these animals' biology.

"All animal adaptation come[s] with both benefits and costs," study senior author Kirt Onthank, a marine biologist and biology professor at Walla Walla University in Washington, told Live Science. "We know a lot about the benefits of the octopus color change system, but until now we have known virtually nothing about the costs. By knowing the costs of color change to the octopus, we have a better understanding of what types of trade-offs octopuses are making in order to stay hidden."

Like many other cephalopods, octopuses have a special set of small organs in their skin called chromatophores.

Related: How do octopuses change color?

"Each chromatophore is a small, stretchy sac of pigment that has rays of muscles attached to it like spokes of a wheel attached to the hub," Onthank said. "When the muscle[s] are relaxed, the sac of pigment is collapsed to a small point that is generally too small to see. When the muscle[s] contract, they stretch this sac of pigment out over a small patch of skin, and the color inside can be seen."

Each of these chromatophores is like a tiny pixel on a screen. "Octopuses have 230 chromatophores per square millimeter on their skin," Onthank said. "To put this into context, a 4K 13-inch laptop monitor has about 180 pixels per square millimeter."

To change color, thousands of tiny muscles in these pixel-like organs contract. "By controlling each of these chromatophores with their nervous system, they [octopuses] can create very elaborate and impressive camouflage or displays," Onthank said.

In the new study, published Nov. 18 in the journal PNAS, Onthank and first author Sofie Sonner, who conducted the research as part of her master's thesis at Walla Walla University in Washington state, collected skin samples from 17 ruby octopuses (Octopus rubescens) and measured oxygen consumption during chromatophore expansion and contraction. They then compared this to each octopus's resting metabolic rate.

The average octopus used about 219 micromoles of oxygen per hour to fully change color—roughly the same amount of energy they use to carry out all other bodily functions when at rest, the study found.

By scaling up their calculations to match human surface area, Onthank said that, if our species had color-changing octopus skin, we would burn roughly 390 extra calories a day changing color — about the same as completing a 23-minute run.

Octopuses and cephalopods aren't the only animals that can change color. "Rapid color change has evolved independently multiple times across a diverse array of animal taxa, including in amphibians, reptiles, fish, arthropods, and mollusks, which shows its widespread adaptive significance," Sonner told Live Science.

However, cephalopods' color transformations are much quicker and more precise. "Most other animals that can rapidly change color, like chameleons, use hormones to control the system and pigments inside cell[s]," Onthank said. Those methods are slower but probably also use less energy, he added.

The researchers hope to use their system to measure energy expenditure in other cephalopod species, as well as deep sea octopuses, to better understand these energetic trade-offs and, in turn, to gain new insights into octopus biology.

Scuba-diving lizards have an aquatic trick up their sleeves: They can create air bubbles on their foreheads to breathe underwater, enabling them to stay submerged for long periods and escape predators, researchers say.

In 2018, scientists captured the first-ever footage of a semi-aquatic lizard known as a stream anole (Anolis oxylophus) breathing underwater using a bubble of stored oxygen surrounding its snout — an ability that had never been seen before in lizards. Since then, at least 18 other species of anoles have been found to do this too, including water anoles (Anolis aquaticus).

However, until now, researchers had no idea if this bubble enabled these lizards to stay underwater for a long time or if it merely formed as a side effect of their water-repelling skin.

In a study published Sept. 18 in the journal Biology Letters, researchers tested nearly 30 water anoles and found that those using air bubbles stayed underwater 32% longer than anoles without bubbles. In the wild, this extra time underwater likely helps them to evade predators.

"There are a lot of threats in their environment, and it makes sense that they would evolve a unique way of dealing with them using the resource — water — that they have available," study author Lindsey Swierk, assistant research professor in biological sciences at Binghamton University in New York, told Live Science in an email.

Related: Watch chameleon erupt in color 'as if uttering her last words' in her final moments before death

Semi-aquatic water anoles spend most of their time living on boulders close to river banks in forests in Costa Rica and Panama. They are small lizards that can grow up to 8 inches (20 centimeters) long. When threatened, they have been observed jumping into nearby water to escape.

"We know that they can stay underwater at least about 20 minutes, but probably longer," Swierk said.

Upon diving, these anoles exhale to create a bubble that surrounds their head, held on by the lizards' water-repelling skin. "When water anoles dive, their hydrophobic ("water-repelling") skin keeps a slick of air over the body surface," Swierk said.

As the anoles exhale and inhale, the bubble expands and collapses. The researchers suggest this redistributes air on and in an anole's body, giving it sufficient oxygen for long dives.

To test this, scientists collected 28 water anoles from the Rio Java in Costa Rica. The team applied a substance to 13 of the anoles' heads to stop their skin from being water repellant, meaning the bubble would fail to attach, Swierk said.

"We then compared the dive length and the ability to rebreathe bubbles in anoles with and without emollient applied," Swierk said.

In the control group — the anoles with no substance applied — the longest dive recorded was 477 seconds (nearly eight minutes), although this was excluded from the analysis for being an outlier. The longest dive included in the analysis was 308 seconds (just over five minutes). In the group with the substance applied, the longest dive was 254 seconds (over four minutes).

On average, anoles without the substance applied spent 67.5 seconds longer underwater than those with the substance. "These results show that when semi-aquatic anoles are allowed to rebreathe using bubbles, they can dive longer," Swierk said.

Swierk suggests the difference between dive times may have been greatly different if this experiment was conducted in the wild and not in tanks. "The pressure to stay concealed from a real predator, which we didn't use in our study, could nudge the control group's dive times much longer," Swierk said.

Anoles are not the only animals known to use bubbles underwater. For example, diving beetles carry trapped air behind them at the tip of their wing covers. This bubble acts as a "physical gill," exchanging oxygen with the water to replenish the supply inside the bubble.

The team now wants to find out if water anoles use their breathing bubbles in the same way.

A hungry whale mid-gulp, a lazy seagull riding a sea turtle, an adorable-yet-deadly mini octopus and a group of alien-looking fish babies fused to eggs were some of the stars of a recent ocean photography competition.

The stunning images were among those short-listed at the 2024 Ocean Photographer of the Year awards. The winners of the competition, which is run by Oceanographic Magazine and sponsored by the Swiss watch company Blancpain, were announced Thursday (Sept. 12) at an event in London's Somerset House.

In total, more than 80 photos were short-listed across 10 categories, and you can see the best ones below.

Related: Under the sea: 50 breathtaking images from our oceans

The standout image was a high-definition shot of a Bryde's whale (Balaenoptera edeni) about to gulp down a massive "bait ball" of fish. Photographer Rafael Fernández Caballero captured the stunning shot in Baja California, Mexico, and took home first place in the Ocean Photographer of the Year category.

"A feeding frenzy is the biggest show on earth for me," Fernández Caballero said in a statement. "The highlight was this whale coming out of nowhere with its mouth wide open." But there was a wide range of other species involved in the banquet, which was likely caused by the recent El Niño event, they added.

One of the standout images short-listed in the Fine Art category was a shot from Enric Gener showing a lone seagull casually sitting on a turtle's shell floating in the middle of the Mediterranean Sea.

After five hours of scanning the empty ocean for something to photograph, Gener spotted a seagull with its legs out of the water and was shocked when he realized it was standing on a sea turtle.

"I decided to jump into the water, thinking I would find the turtle dead because it wasn't moving," Gener said in a statement. "When I got close enough, I saw its face underwater and realised that the sea turtle was alive."

The runner-up in the Ocean Portfolio category was Katherine Lu, who captured a peculiar deep-sea scene in the Philippines. It shows a juvenile poison ocellate octopus (Amphioctopus mototi) planted on a pyrosome, a free-floating colonial creature made up of single-cell tunicates embedded in a gelatinous "tunic."

"Each night during the vertical migration, deep-sea creatures like this octopus migrate upwards to the lighter, shallower waters to feed and avoid predators before descending back into the depths by morning," Lu said in a statement. But hitching a ride on the pyrosome makes this daily migration much easier, she added.

The tiny octopus, which was around 0.8 inch (2 centimeters) tall, contains the same toxin as blue-ringed octopuses (Hapalochlaena), which are among the deadliest animals on Earth.

First place in the Ocean Portfolio category went to Shane Gross, who photographed a bizarre litter of baby plainfin midshipman fish (Porichthys notatus) off the coast of British Columbia, Canada. The wide-eyed juveniles sat atop glowing orange yolk sacs, which they were still attached to at the time.

The vulnerable younglings remain tied to their eggs and "are guarded over by their father until they are big enough to swim out from under the rock they are living on," Gross explained in a statement. Once they leave their den, the fish will swim off into the deep sea and won't return to the shallows until it is their turn to breed, Gross added.

In the Wildlife Photographer of the Year category, Gross was also short-listed for an eye-catching image of a peppered moray eel (Gymnothorax pictus) lying slumped over rocks between two intertidal pools on D'Arros Island in the Seychelles.

A pair of smaller eels can also be seen slithering out of water in the foreground. "Their ability to come completely out of the water is amazing and surprising," Gross said.

You can check out more of the amazing images below.

New footage shows a "flying spaghetti monster" waving its many arms nearly 2,200 feet (665 meters) below the surface, near an underwater mountain off the coast of Chile.

Scientists captured the footage with a remotely operated vehicle (ROV) deployed from the research vessel Falkor (too) close to a previously unexplored seamount on the Nazca Ridge, an underwater mountain chain in the southeastern Pacific Ocean. In the video, the spaghetti monster (Bathyphysa conifera) is filmed up close, revealing the creature's pink-tipped, sausage-like arms and other filamentous appendages.

"The seamounts of the Southeastern Pacific host remarkable biological diversity," Alex David Rogers, a marine biologist and science director at Ocean Census, a global program that aims to accelerate the discovery of marine species and participated in the discovery, said in a statement.

Researchers spotted the flying spaghetti monster roughly 900 miles (1,450 kilometers) off the coast of Chile, near a little-known seamount that towers 10,200 feet (3,109 m) above the seafloor.

Related: Watch hypnotizing footage of mysterious deep-sea worm dancing in the twilight zone

Flying spaghetti monsters are colonial organisms made up of thousands of multicellular "zooids" that each contribute to a specific function, such as reproduction or digestion. Spaghetti monsters are carnivorous and typically live between 3,300 and 9,900 feet (1,000 to 3,000 m) deep. They can grow several feet long, according to the statement.

The expedition that captured the new footage, led by the Schmidt Ocean Institute, is the third of its kind to explore mountain chains off the coast of Chile this year. Previous expeditions between January and February uncovered more than 100 new species and a gigantic seamount along the Nazca Ridge and neighboring Salas y Gómez Ridge.

The three expeditions have increased the number of known species in the southeastern portion of the Pacific Ocean from 1,019 in 2023 to more than 1,300 currently, according to the statement.

The research "will significantly enhance our understanding of the distribution of remarkable lifeforms on these underwater mountains, including several that have never before been mapped or seen by human eyes," Rogers said.

During the recent dive, researchers also captured the first ever footage of a live Promachoteuthis squid — a type of small, weak-muscled squid that scientists had previously only described from dead specimens — and videos of a Casper octopus, a creature so new to science it doesn't have a scientific name yet.

A 1-in-100-million "cotton-candy" lobster that exhibited vibrant pink, purple and blue hues was caught by a lobsterman off the coast of New Hampshire in late July.

Joseph Krame, the 25-year-old who caught the specimen, donated his rare catch to the Seacoast Science Center in Rye, New Hampshire where the lobster, which is said to be "healthy and eating well," can now be seen on public display, Karen Provazza, a staff member of the Seacoast Science Center, told Live Science in an email.

Lobsters are typically a mottled brown color, which helps camouflage them on the ocean floor. However, lobsters are also found in a variety of colors at lower frequencies including orange, blue, and even two-toned. The reason for this variation is due to genetic mutations that change the chemistry of a pigment they ingest.

All lobsters take in a red pigment, called astaxanthin, that comes from the plants and smaller crustaceans they eat. It's this pigment that gives lobsters their striking red coloration after cooking, and also their natural mottled brown appearance.

The lobster exterior is made up of layers; first the skin, followed by two layers of shell. After ingestion, the red pigment is stored in the skin layer. The pigment then moves into the lower shell, which appears blue, due to interactions with proteins present in the shell that twists the pigment. Finally, when the pigment moves into the upper shell the pigment interacts with different proteins to create a yellow hue.

Related: 'You can see its guts and things': Weird see-through crustacean with giant eyes discovered off the Bahamas

So when we look at a lobster, we are in fact looking through each of these layers - a yellow, blue and red layer — and this gives the lobster a mottled brown appearance. Cooking the lobster breaks down these proteins, returning astaxanthin to its distinctive red color.

The variation in lobster coloration comes from genetic mutations that change the way this pigment interacts with proteins in the shell. Blue lobsters carry a mutation that produces more of the proteins in the lower shell layer, which pulls more of the red pigment from the skin into the shell layer. This mutation is present in around one in 2 million lobsters.

"Cotton candy" lobsters are even rarer — occurring at a frequency of about 1-in-100-million. The precise genetic causes of this coloration is unknown, but it's thought that something disrupts the normal pigmentation process, allowing more of the red astaxanthin to be seen through the blue layer. The result is "a mixture of pinks and purples on a blue backdrop resembling cotton candy," Provazza said.

In addition to the lobster's DNA, diet may also alter its color. The intensity of color hues in lobsters with mutations that predispose certain color variants will depend on their diet. For example, if the lobster is mostly fed on bait fish they would ingest less astaxanthin, compared to a typical lobster diet of astaxanthin-rich crab and shrimp.

So why are these lobster color variants so rare? Firstly, mutations underlying these variations will occur at a very low rate. In addition, brightly-colored lobsters are less able to hide on the ocean floor, making them likelier to be preyed upon, thus lowering the odds of them surviving long enough to pass on their genes.

The cotton candy lobster, estimated to be between 8 and 10 years old, will spend the rest of its days at the Seacoast Center in New Hampshire, safe from predators and New England summer lobster bakes. It joins another cotton candy lobster caught in November 2021.

Eerie new footage captures a rare, otherworldly scene: a giant jellyfish with a tiny isopod swimming around in its bag-like body. In the video, the translucent blob contracts its veiny membrane as it floats in the twilight zone with the bright-orange isopod, a type of crustacean, inside its bell.

Scientists with the Schmidt Ocean Institute spotted the elusive creature at a depth of 2,766 feet (843 meters) during an expedition to the Atacama Trench off the coast of Chile. They identified the jellyfish as belonging to the genus Deepstaria. These jellyfish lack long, stinging tentacles, so they capture their dinner by enveloping prey within their bodies, according to an Instagram post from the institute. The isopod in the video, however, isn't prey: Rather, it is a permanent resident.

Deepstaria jellyfish were first discovered off the California coast in 1966 and were named after Deepstar 4000, the submersible that spotted them. Since then, Deepstaria sightings have been extraordinarily rare.

There are currently two recognized species within this genus: Deepstaria enigmatica and Deepstaria reticulum.

Their exact distribution remains unknown but both species have been found in the Gulf of Mexico, off the coast of California, Caribbean and Central Atlantic Ocean. D. enigmatica has also been observed in the Southern Ocean near the Antarctic. All observations were recorded at depths of around 2,000 to 5,700 feet (600 to 1,750 m), according to a 2018 study.

Related: Alien-like giant phantom jellyfish spotted in frigid waters off Antarctica

Deepstaria jellyfish use their membranous bell to engulf small crustaceans, fish and even other jellyfish, closing their bell to keep prey trapped inside. This motion allows isopods to enter the body of the jellyfish.

The footage reveals the veiny network of the gastrovascular system on its body, which is important for digesting and delivering food to the stomach at the top of the animal's bell, according to the post.

"We are seeing a large scyphozoan jellyfish called Deepstaria enigmatica which belongs to the family Ulmaridae, the same family as the common moon jellyfish," said Allen Collins, curator of Porifera, Medusozoa and Ctenophora at the Smithsonian's National Museum of Natural History, who was not on the expedition.

"On the underside of the subumbrella (up inside the bell) we can see an isopod, Anuropus bathypelagicus that is often (always perhaps) associated with this jelly," Collins told Live Science in an email.

A. bathypelagicus is a large, blind isopod that can grow to more than 3 inches (8 centimeters) long. Researchers have spotted Anuropus living in both species of Deepstaria and using hooked appendages to grip onto their bodies.

In 1969, a study using the Deepstar submersible reported observations of D. enigmatica with abnormal, almost motionless swimming movements. As the submersible moved, the wave of water flipped the jellyfish on its side, revealing a small Anuropus isopod clinging to its body.

When examined, the jellyfish was missing body parts, including its stomach and the lining of its body, which explained its flaccid behavior and led to suspicions that the isopod might be feeding on the jellyfish. Jellyfish remains have also been found in the stomach contents of A. bathypelagicus, which further supports the notion that the isopod eats its Deepstaria host, Collins said.

However, this could also suggest that the isopod feeds on the captured prey within the Deepstaria.

"Just a handful of papers have mentioned it and no one specifically has traced the isopod actually eating the Deepstaria host," Collins explained.

As the jellyfish floats in the water column, the isopod may benefit by using the giant blob as a vehicle and protection from predators. "The isopod is blind and likely benefits by getting a ride on the jellyfish and perhaps a safer place to hide," Collins said. What, if anything, Deepstaria gets out of the relationship is unclear.

A young male octopus gets comically dragged around the ocean floor mid-sex by an impatient female in rare new footage. 

The clip, filmed for the new National Geographic miniseries "Secrets of the Octopus," reveals an algae octopus (Abdopus aculeatus) in shallow water just off the coast of the island of Bunaken in Indonesia. The footage captures the moment he spots a female and begins his courtship with a passing cloud display — a behavior thought to be a form of communication, where an octopus' skin changes color in a wave-like manner. 

"The passing cloud display means different things to different cephalopods," series producer Adam Geiger told Live Science in an email. "With the algae octopus, the passing cloud display seems to be an expression of interest in mating… a general 'I'm available' signal." 

Related: Octopuses torture and eat themselves after mating. Science finally knows why.

After the female responds with her own colorful display, he makes his move, sticking up a papilla —  a skin bump the octopus can control to change its body shape — above his eye. He also creates a black and white striped pattern on his back to indicate he wants to fight or mate, marine biologist and filmmaker Alex Schnell says in the clip.   

The female is receptive, so he extends his specialized mating arm, known as a hectocotylus, and awkwardly attempts to find her mantle cavity — a muscular structure containing the vital organs, where sperm is deposited during mating. But he appears to take too long, and the female gets "impatient and hungry," series narrator Paul Rudd says in the footage. 

The female then starts pulling the male around as he hangs on with his hectocotylus. "It was surprising, and comical, to witness mating on the move," Geiger said. "The female [is] essentially dragging the male — hanging on for dear life — over the reef while she got on with other things. The Algae octopus were the only species in the series we witnessed mating this way, but who knows, others may do this, too." 

Observing octopus sex is relatively rare, and researchers have only observed mating behaviors in about a dozen species, Jennifer Mather, a cephalopod expert at the University of Lethbridge in Canada, told Live Science in 2015. 

Most octopuses live solitary lives, only coming together to mate, but the algae octopuses in the new series were surprisingly social, Geiger said.

"We were thrilled by how frequently they interacted — just saying hello, fighting, or mating. But they move very quickly through their little community, so following an individual was really tough," he added. "On one lucky day, after weeks of filming, we managed to track our hero for more than two hours until he successfully found a receptive female."

Algae octopuses are also pretty small — their bodies are around 3 inches (7 centimeters) and their arms are around 10 inches (25 cm) long. They were in water that was just 24 inches (60 cm) deep, so even tiny surface waves tossed them around. This made filming the interactions even tougher, Geiger said.

"Imagine trying to look through a straw to follow an ant, in a hurricane! Keeping a camera steady and the image composed and focussed while being sloshed about made filming these quick-moving octopus one of the most challenging sequences of the series," Geiger said. "Even with our team's nearly 80 years of combined experience filming underwater, the physics of these conditions were unique."

"Secrets of the Octopus" premieres on April 21 at 8 p.m. ET on National Geographic and is available to stream on April 22 on Disney+ and Hulu.

How to watch "Secrets of the Octopus"

You can watch "Secrets of the Octopus" on the cable channel National Geographic on Sunday, April 21 at 8pm ET. After that you can stream the show on Hulu in the U.S. and Disney Plus worldwide on April 22.

If you don't have cable, there are a few options you can try to watch the show. FuboTV has an entry-level Pro Plan, which gives you over 100 channels for $74.99 a month, but if you just want to dip your tentacles in (or should that read arms?) also comes with a free 7-day trial. Otherwise you could give Sling TV a go, which is currently $20 a month for the Sling Blue plan, a 50% saving on its standard price.

The oldest known sex chromosome in animals has been discovered, pushing back the date for the evolution of sex chromosomes to between 248 million and 455 million years ago. 

The ancient chromosome was found in octopus and squid, suggesting that these may have been among the first animals to determine their sex via genetic blueprint, instead of environmental cues.

Sex chromosomes are standard in mammals. In humans, the sex chromosomes are X and Y. Males usually have an X and a Y chromosome, while females have two Xs, although there are some variations, such as XXX or XXY, which can have a wide range of impacts from no effect at all to certain learning disabilities or neurological differences. 

For a long time, researchers weren't sure whether cephalopods, the soft-bodied mollusks that include squid and octopuses, determined their sex with chromosomes. Mollusks have a variety of ways to handle reproduction, including hermaphroditism or sequential hermaphroditism, in which individuals swap sexes over time.

Octopuses stick to one sex, but it wasn't clear whether genes or environmental cues determined what sex that would be. In some reptiles and fish, factors like temperature decide the sex of offspring.  

Related: Octopuses torture and eat themselves after mating. Science finally knows why.

In 2015, researchers completed the first full gene sequence of a cephalopod, the California two-spot octopus (Octopus bimaculoides). That sequence still included gaps, though, so a team led by Andrew Kern, a biologist at the University of Oregon, set about filling them in with high-fidelity sequencing. 

They soon noticed that one chromosome, chromosome 17, seemed less filled-out with genes than the other chromosomes in their sequence. Because they had sequenced a female octopus, they compared their results to the earlier individual, a male. In the case of the male, chromosome 17 looked no less populated than other chromosomes in the octopus. 

This was a clue that chromosome 17 might have something to do with sex differences. To confirm, the team sequenced four more octopuses, two male and two female, and confirmed that females have just one copy of chromosome 17, while males have two. Thus, they represent the octopus sex chromosomes not as XY and XX as in humans, but as ZZ and Z0.

The researchers then compared their octopus genomes to the genomes of three other octopus species, three species of squid, and the chambered nautilus (Nautilus pompilius).

They found the ZZ/Z0 pattern in the squid and the octopus, but not in the nautilus, a more distantly related species. This showed that the sex chromosomes evolved after the split between the nautilus line and the line leading to modern squid and octopus, which occurred between 455 million and 248 million years ago.

"This is an astoundingly long time for a sex chromosome to be preserved," the researchers wrote in their paper, which is now available pre-peer review on the preprint website BioArxiv. 

Prior to this research, the oldest confirmed sex chromosome was in sturgeon fish, according to Nature News, with an age of about 180 million years.  

Using LED lights and glow sticks, scientists in the Bahamas have discovered an ancient deep-sea crustacean with giant eyes and a see-through body. 

Although the species, which they named Booralana nickorum, is newly identified, it has been on the planet for 300 million years and may play a crucial role in maintaining the health of the ecosystem, the researchers wrote in a study published Jan. 12 in the journal Zootaxa.

The new species has a hard exoskeleton; a segmented body; and big, compound eyes to find potential prey. As it lives in the deep sea, where there's very little light, it has no need for color or pigmentation, so it's white, and even slightly translucent. 

"You can see its guts and things," study co-author Nicholas Higgs, director of research and innovation at the Cape Eleuthera Institute, told Live Science.

Related: Creepy deep-sea 'vanilla Vader' woodlouse is 25 times bigger than a land louse 

At around 2.2 to 3 inches (55 to 76 millimeters) long, it's much larger than its terrestrial cousins in the pill bug family — also called roly poly bugs or woodlice — which measures around 0.55 inch (14 mm). B. nickorum's large size gives the deep-sea scavenger an advantage as it waits on the seabed for food to fall from above. 

"The bigger you are, the more you can get from any one meal," Higgs said, and the longer the animal can last between meals, which is important in this environment, where food is scarce. 

The team discovered B. nickorum at depths of between about 1,770 and 1,840 feet (540 to 560 meters) on an underwater slope in the Bahamas' Exuma Sound. They obtained the specimens during two expeditions, in April 2014 and February 2019, operated by OceanX and the Cape Eleuthera Institute. In 2014, they put down baited eel traps, which caught deep-sea isopods — a type of crustacean with a flattened, segmented body — so they returned in 2019 to investigate further using light traps. Instead of bait, these units had a flashing, multicolor LED fishing light; a green glow stick: a green, deep-drop LED fishing light; and a programmable white LED light to attract creatures by mimicking the bioluminescence generated by deep-sea animals. 

As soon as the researchers examined the specimens on board the ship, they were confident that the species was "definitely different from anything we've seen before," Higgs said. 

Further tests confirmed that B. nickorum was a new species. It was named after two members of senior author Edward Brooks' family, both called Nicholas Brooks.

These isopods play a critical role in the ecosystem by speeding up the decomposition of plant or animal matter so the wider ecosystem can benefit from these energy sources. "Otherwise, it would just sink down and remain locked away in the sediment," Higgs said.

These crustaceans also ensure that the carbon within the organic matter falling from the shallows is captured in the deep ocean for thousands of years. 

Finding new species like these helps researchers understand whether animals in the deep ocean are endemic to one place or disperse from one region to another over time. This enables scientists to better predict the ripple effect of human activities, such as mining. "If you impact one site, is that going to impact animals in a different area?" Higgs said.

With more countries like the Bahamas considering deep-sea oil exploration, Higgs believes expeditions like these are vital in helping decision-makers understand how drilling could affect their precious ecosystems. 

"As long as we don't have access to this environment," he said, "we're not going to appreciate it, we're not going to understand it, and we're not going to value it.”

Last month a team of scientists visited an ethereal nursery on the seafloor off Costa Rica, where they watched in awe as a new generation of deep-sea octopuses gently emerged from a quivering cluster of oblong, semitranslucent eggs.

Now the researchers have confirmed these deep-sea dwellers are members of an entirely new, yet-to-be-named species, nicknamed the "Dorado octopus." And they have announced they've discovered three more new deep-sea octopus species on top of that.

"Finding four new species of octopuses on just two expeditions is exciting, revealing some of the rich biodiversity of the deep sea and hinting at how much more waits to be discovered," says Jim Barry, a deep-sea ecologist at the Monterey Bay Aquarium Research Institute, who was not involved in the expeditions.

The nursery visit last December was part two of a Schmidt Ocean Institute expedition that took place six months earlier. Then, too, researchers witnessed baby deep-sea octopuses emerge from eggs that their respective mothers were brooding near hydrothermal vents on the same underwater rock formation, called the Dorado Outcrop (hence the new species' nickname). The octopuses' proximity to the vents suggests these creatures may have evolved to use warmth from the seeping hydrothermal fluid to accelerate the incubation process—which is notoriously long for many deep-sea creatures, leaving their offspring vulnerable to predators for extended periods.

The team collected some octopus specimens near the vents and others farther away and brought them to the Zoology Museum at the University of Costa Rica. Fiorella Vásquez, a research assistant at the Zoology Museum, and Janet Voight, associate curator of invertebrate zoology at the Field Museum of Natural History in Chicago, then set out to classify the creatures.

The Dorado octopus is remarkably similar to the pearl octopus (Muusoctopus robustus), which a separate team of researchers previously found brooding eggs near hydrothermal vents off central California. To distinguish the Dorado octopus as a separate species in the recent investigation, the scientists made careful observations and descriptions of the different octopuses, such as measuring their arms and enumerating their suckers. "The two species share an unusual morphology, having smallish eyes, a robust body and fairly short arms," Voight explains. "It's the details that separate them."

Of the three additional species the team identified farther from the hydrothermal vents, two are also members of the genus Muusoctopus. They have double rows of suckers on their arms and lack an ink sac––other traits that are characteristic of the genus.

"But they look really different," Voight says of these two species. For both, large eyes are the most obvious difference from the Dorado octopus. And one of the species is reddish, with long arms, while the other has a lighter shade on its top side and a darker one underneath.

The fourth species is an oddball. "It was just so unlike anything I had seen; I didn't know where to assign it," Voight says. But she and Vásquez observed a single row of suckers on each of the animal's arms and strange bumps on its skin, which they say could place this species in the genus Graneledone. Voight notes, however, that "its bumps aren't quite like what I expected to see, and it's really pale-colored, so it's a bit of an enigma."

These three other newfound species are also officially nameless so far. The researchers collected additional specimens that they're still poring over to determine the best classifications. Subsequently they'll have to meticulously describe and illustrate each species, run that information through peer review and then, if accepted, the species names will enter the scientific literature.

"We have so much to explore in the deep ocean, and part of that exploration is to find new species," Vásquez says. "Every step we take to learn a little more about what is at the bottom of our ocean will help us to conserve it."

The expedition also identified a rare deep-sea skate nursery — which the scientists are calling Skate Park — and three new hydrothermal springs. Expedition co-leader Jorge Cortés-Núñez, a professor emeritus of biology at the University of Costa Rica, says "we have samples and data for many years to come, motivation to continue along that line of research, and powerful information and images to justify the protection and conservation of the deep sea, not only of Costa Rica but of all the ocean."

This article was first published at Scientific American. © ScientificAmerican.com. All rights reserved. Follow on TikTok and Instagram, X and Facebook.

Crabs have evolved to migrate from the sea to land then back again multiple times over the last 100 million years, scientists have discovered. 

A new study, published Nov. 6 in the journal Systematic Biology, found that true crabs (Brachyura) — which consist of 7,600 species across 109 families — have evolved to migrate from marine to land habitats between seven and 17 times. (True crabs are distinct from other crustaceans that have developed crab-like bodies).

They also found that on two or three occasions, crabs even went back to the sea from land. "It is 100% harder going from being on land to water," lead author Joanna Wolfe, a researcher in organismic and evolutionary biology at Harvard University, told Live Science. 

Related: Why do animals keep evolving into crabs?

Most arthropods left the ocean just once during evolutionary shifts more than 300 million years ago, in a process known as terrestrialization. 

In the new study, researchers set out to discover how often and when true crabs left the marine environment for land. They compiled three new datasets for 333 species of true crabs from 88 families, including both marine and non-marine groups. 

Using the entire crab fossil record, the researchers applied two mapping pathways: one where the crab goes from a fully marine environment to land directly through intertidal zones such as beaches, and a second where the species migrates from fully marine to land indirectly, through estuaries, fresh water, riverbanks, coastal forests and jungles.

Their findings enabled the team to classify each crab species into a gradient of terrestriality — or how suitable they are to life on land. Using methods originally developed to study how viruses like COVID-19 evolved, the researchers determined the timing of true crab evolution. 

Their findings  suggest that true crabs emerged about 45 million years earlier than previous estimates and could date back to the mid-Triassic period (251.9 million to 201.3 million years ago), making them as old as some of the earliest known dinosaurs.

They left the ocean between seven and 17 times as a result of convergent evolution — when different organisms independently evolve similar traits. 

Most crabs, they found, are only able to survive in semi-terrestrial habitats, with land-based crabs found to be concentrated in one species-rich group of the family tree. "It is a common misconception that crabs are trying to evolve to live permanently on land. Most crab species still flourish in the ocean," Wolfe said. 

More than 10 billion snow crabs recently vanished from the Bering Sea, and now we know why: They fell victim to one of the biggest marine heat wave die-offs on record, new research shows.

The deadly heat wave, which struck polar waters between Alaska and Siberia in 2018 and lasted for two years, triggered record-high ocean temperatures and historic declines in sea ice. These "unprecedented" circumstances brought a large population of snow crabs (Chionoecetes opilio) living in the eastern Bering Sea to its knees, according to a new study, published Thursday (Oct. 19) in the journal Science. 

"The collapse of the snow crab population was a strong response to a marine heatwave," researchers wrote in the study. Rather than succumbing directly to warm ocean temperatures, however, it appears the crabs died of starvation.

Snow crabs are small, round-shelled crustaceans that can live for up to 20 years on soft seabeds that are less than 650 feet (200 meters) deep, according to the National Oceanic and Atmospheric Administration (NOAA). The species is closely monitored and managed in the eastern Bering Sea due to its commercial value as seafood.

Related: Why do animals keep evolving into crabs?

Scientists first noticed a dramatic drop in the number of snow crabs during a survey in 2021, which "found the fewest snow crab on the eastern Bering shelf since the survey began in 1975," researchers wrote in the study. No survey was conducted in 2020 due to the coronavirus pandemic, which is why scientists only noticed the crabs had disappeared the following year. But until now, the cause of the population collapse remained a mystery.

It turns out that warm water temperatures caused by the heat wave probably affected the metabolism of the crabs and increased their caloric needs, according to the study. Previous research conducted in a laboratory found that snow crabs' energy requirements doubled when water temperatures rose from 32 degrees to 37.4 degrees Fahrenheit (0 degrees to 3 degrees Celsius). This jump in temperature is equivalent to the change experienced from 2017 to 2018 by juvenile snow crabs, which live in frigid waters known as the "cold pool" and migrate to warmer spots as they mature, according to the study.

Snow crabs' increased caloric needs were reflected by a change in body size between 2017 and 2018, with smaller crabs caught during a survey after the heat wave had begun, according to the study.

The snow crabs also fell victim to bad timing. Right around the time of the heat wave, the crab population in the eastern Bering Sea had boomed, according to the study. The combination of more crabs and higher caloric needs proved deadly.

Other factors — such as predation by Pacific cod (Gadus macrocephalus), cannibalism of smaller crabs by larger ones, fishing and disease — likely contributed to the mortality event, but "temperature and population density were the key variables in the recent collapse," they added. 

The effects of rapidly rising ocean temperatures and more frequent heat waves in response to climate change are difficult to predict, researchers wrote in the study, but the snow crab die-off is "a prime example for how quickly the outlook can change for a population."

And while the future of snow crabs in the eastern Bering Sea is now "precariously uncertain" as they haven't recovered from the mortality event, the population may eventually find refuge in colder waters further north. How the mass death might affect the wider ecosystem remains unclear.

"The problems currently faced in the Bering Sea foreshadow the problems that will need to be confronted globally," the researchers wrote. "The disappearance of snow crab will be a staggering blow to the functioning of some communities in rural Alaska, such as those on St. Paul Island, which rely strongly on the revenue derived from the capture and processing of snow crab."

Two fishers from Australia were recently airlifted to hospital after being stung by one of the most venomous jellyfish in the world while they were far out on the ocean. 

The two unnamed men were on a boat around 12 miles (19 kilometers) off the coast of Dundee Beach in Australia's Northern Territory when they were stung by an Irukandji jellyfish on Oct. 10, Australian news site 7News reported.

There are 16 known species of Irukandji jellyfish, which are all endemic to the deep seas around northern Australia. The venom of each of these tiny box jellyfish can trigger Irukandji syndrome — an extremely painful and potentially deadly set of reactions. 

It is unclear which species stung the two fishers, but most cases of Irukandji syndrome are caused by Carukia barnesi, according to the National Center for Biotechnology Information (NCBI). The species is only around 0.8 inch (2 centimeters) long but is one of the most venomous marine creatures on Earth.

The two men were airlifted to hospital from their boat and were discharged 48 hours later. Both are expected to make a full recovery, 7News reported.

Related: What's the difference between poison and venom? 

C. barnesi administer their toxins using specialized stinging cells, known as nematocysts, which line their four tentacles and fire venom-filled barbs into their prey or as a defense mechanism against predators, according to the Australian Museum. Due to their small size, most people are unaware of the jellyfish until they have been stung.

Irukandji venom works in a similar way to tetrodotoxin, one of the world's most potent venoms that is administered by animals such as pufferfish and blue-ringed octopuses, according to NCBI. Both toxins stop nerves from properly signaling to muscles by blocking sodium ion channels. 

The symptoms of Irukandji syndrome include shooting pains in muscles, backache, headache, nausea, vomiting, anxiety, hypertension, breathing problems and cardiac arrest, according to NCBI. Although most people make a full recovery, there are cases of people continuing to experience pain up to a year later. Symptoms can begin as soon as five minutes after being stung, according to the Queensland Ambulance Service (QAS).  

Like with tetrodotoxin, there is no known antivenom for Irukandji venom, and treatment is only supportive, according to NCBI. Experts recommend immediately dousing the sting area with vinegar because its acidic properties can prevent the barbs from releasing their venom, according to QAS.

On average, there are between 50 and 100 cases of Irukandji syndrome in Australia every year, according to NCBI. Most cases occur in the summer when warmer waters and high winds push the jellyfish to the surface and toward land, but cases have been documented in every calendar month. Two people — an American scientist and a British tourist — are known to have died from Irukandji syndrome, Scientific American previously reported. 

Another two people, both French tourists, are suspected of being killed by Irukandji stings in a single snorkelling incident, Australian news site ABC News previously reported. But they were both elderly and had underlying health conditions, which made it hard to determine an exact cause of death.

Australia is also home to several of the world's most venomous sea creatures, including other box jellyfish, stonefish and blue-ringed octopuses, each of which have killed multiple people.

A stunning image of a golden horseshoe crab shuffling along the seabed with three striped fish overhead has won this year's Wildlife Photographer of the Year competition.

Laurent Ballesta, a French underwater photographer and marine biologist, captured the striking scene in the protected waters of Pangatalan Island in the Philippines, a refuge for endangered tri-spine horseshoe crabs (Tachypleus tridentatus).

These horseshoe crabs have existed for more than 100 million years, award representatives said in a statement shared with Live Science, but they now face habitat destruction and dwindling food due to overfishing. Humans also harvest them for their unique blue blood, which is used in the development of vaccines.

"To see a horseshoe crab so vibrantly alive in its natural habitat, in such a hauntingly beautiful way, was astonishing," Kathy Moran, chair of the jury for the competition, said in the statement. "We are looking at an ancient species, highly endangered, and also critical to human health. This photo is luminescent."

Related: Why do animals keep evolving into crabs?

The three juvenile golden trevallies (Gnathanodon speciosus) hovering over the horseshoe crab were probably there to pick off any edible treats plowed up by the crab's slow advance, according to the statement.

The jury selected Ballesta's photo, titled "The golden horseshoe," from among almost 50,000 entries from 95 countries. Another 18 winners received prizes for showcasing the rich diversity of life on Earth.

"Whilst inspiring absolute awe and wonder, this year's winning images present compelling evidence of our impact on nature — both positive and negative," Doug Gurr, director of the Natural History Museum, which stages the competition, said in the statement. 

The winning images will be on display in the "Wildlife Photographer of the Year" exhibition at the Natural History Museum in London from Friday, Oct. 13 until June 30, 2024.

This isn't the first time Ballesta has received the Wildlife Photographer of the Year award. In 2021, he received the top prize for his photograph of camouflage groupers (Epinephelus polyphekadion) swimming in a milky cloud of eggs and sperm in Fakarava, French Polynesia, in the South Pacific Ocean. 

If you want to try your hand at capturing the wonders of nature, check out our beginner's guide to wildlife photography and our pick of the best wildlife photography cameras.

The deep sea, which encompasses waters below 660 feet (200 meters), is home to roughly a million species that have adapted to their extreme surroundings with equally extreme solutions to one of life's greatest trials: finding a mate. In the excerpt below from "Deep Sea: 10 Things You Should Know," ocean explorer Jon Copley takes a deep dive into the astonishing sex lives of animals living in the darkest corners of our planet. 

All animals face similar trials in life: searching for food, avoiding being eaten, finding a mate and rearing their offspring, and then those offspring finding a home. And just as deep-sea animals overcome the challenge of finding food in lots of different ways, the same is true for those other challenges.

Populations of deep-sea animals often become sparse where food is scarce in the deep sea, which can make it difficult to meet a member of the opposite sex for reproduction. As a result, some deep-sea animals take an opportunistic, "have-a-go" approach to mating. In several species of deep-sea squids and octopuses, for example, males try to mate with any potential partner that they meet, regardless of their sex or even their species.

Mating in squids involves the male passing a spearlike packet of sperm down a groove in one of their arms to stick on to a female's body, ready to release its contents when she produces her eggs. But male squid collected in nets from the deep sometimes have sperm spears stuck on their bodies too, in places where the jabs can't have been self-inflicted, indicating attempted mating by another male. Attempted interspecies mating has also been observed: in 1994 scientists diving in a Human-Occupied Vehicle filmed two male octopuses of different species trying to mate with each other, 2,500 meters (8,200 feet) down on the ocean floor of the eastern Pacific Ocean.

Related: Barreleye fish: The deep-sea weirdo with rotating eyes and a see-through head

As an alternative to indiscriminate mating, some deep-sea animals stay with a partner once they've met them. The sea cucumber Paroriza pallens looks like a moldy banana and spends its adult life crawling across the abyssal plains, leaving a track that can be seen in photographs of the seafloor. Sometimes the single track of a Paroriza meets another, and then the two trails continue side-by-side like a railway line. At the end of those tell-tale twin tracks there's a pair of Paroriza, now wandering across the abyssal plain together.

Paroriza sea cucumbers are hermaphrodites that develop male and female sex organs at the same time, but they can't self-fertilize. Instead, the sperm produced by each partner fertilizes the eggs produced by the other partner. Staying together means that one partner is always available to fertilize the other's eggs whenever they produce them — and the story of their encounter and subsequent fidelity is recorded in their trails on the soft mud of the abyssal plain.

When it comes to keeping a male handy for fertilizing eggs, several deep-sea animals have evolved a more extreme solution. Wood-eating clams, bone-eating "zombie" worms, and some species of anglerfishes have tiny males that attach themselves to a female once they've found her, acting as standby "accessory males" to fertilize the female's eggs when needed. In some species of bone-eating worms, for example, one female can have a harem of a dozen or more males, each about a hundred times smaller than the female, hanging on to her with microscopic hooks.

About two dozen species of anglerfish that live in the deep sea also have accessory males to varying degrees. In some species, the smaller male attaches temporarily to a female, but he can swim off and hook up with another female. In other species, however, the male fuses his mouth onto the female's body in a kiss that lasts the rest of his life. The male's blood supply joins up with hers through his lips, and he can no longer leave her or feed himself: he becomes a parasitic provider of sperm on-tap, nourished by the female through their shared circulation as she continues to feed. In some species, only one male forms this lifelong union with a female, but in others, one female can have several accessory males dangling off her at any one time.

But there's a complication in such a permanent pairing. Fish have an immune system with two main parts like ours. The "innate" immune system produces general defenses to fight off infections, while the "adaptive" immune system recognizes and attacks any "foreign" substances, including cells that are genetically different to the rest of the body. That adaptive immune system is great for tackling would-be invaders, such as disease-causing bacteria, but is a problem when sharing a blood supply with a partner. 

If we were to join our blood supply to that of another person, our adaptive immune systems would attack each other through the shared circulation, unless we were closely related genetically. It's similar to how organ transplants have to be carefully chosen and treated to reduce the risk of being rejected — so how do these deep-sea anglerfish avoid rejecting their partner in the same way?

The anglerfish species with males that attach permanently to females lack several genes that enable their adaptive immune system to recognise cells that are not their own. This means that their adaptive immune systems don't attack each other when they pair up — but it also implies that they may be less able to fight off infections than other fish. It's possible, however, that the innate immune system of those anglerfish species may compensate by producing better general defenses to fight off infection. Further research into how those anglerfish manage without a normal adaptive immune system might even reveal new ways to treat infections in humans.

Text from Deep Sea: 10 Things You Should Know. Reprinted by permission of Orion Publishing.

If you are itching to know more about what lies deep beneath the waves, you can read an interview with Jon Copley here, in which he told Live Science about new discoveries and the biggest myths about the deep sea. 

Scientists have developed a new device inspired by octopus suckers that can deliver drugs without requiring needles or pills. They've already tested it in humans in a small, short trial.

The 0.4 by 0.2 inch (1.1 by 0.6 centimeters) patch can stick to the inner lining of the cheek, stretch across it and increase the absorption of an attached drug.

When used in dogs for three hours, the patch efficiently delivered two drugs — desmopressin, which is used to treat excessive thirst and the urge to pee often, and semaglutide, the active ingredient in Ozempic and Wegovy, drugs that are respectively used to treat diabetes and obesity. A version of the patch without a drug attached was also safely used by 40 human volunteers for 30 minutes while they were able to talk, move around and rinse their mouths with water. 

Further development is needed. However, the patch could represent a less invasive and more comfortable approach to drug delivery, especially for larger drugs that are poorly absorbed by the digestive system so can normally only be injected using needles. 

Related: DeepMind's AI used to develop tiny 'syringe' for injecting gene therapy and tumor-killing drugs

"This is an interesting and well-designed series of studies expanding the range of drug delivery systems inspired by nature," Adrian Williams, a professor of pharmaceutics at the University of Reading in the U.K., who was not involved in the research, told Live Science in an email. "Stretching is known to increase the permeability of mucosal membranes [the protective layer that lines your organs and cavities like the mouth], and is particularly promising for large biological drugs, such as peptides and proteins, which tend to be poorly absorbed and so are usually given by injection." 

Other ways of delivering large drugs to the body, for example via the nose or using microneedles applied to the skin or in capsules, can be inefficient and difficult to make, the study authors wrote. 

"Compared to nasal delivery systems, we would offer something which is much more straightforward to use because you have the drug dose contained in the suction patch, you apply it on your mucosa and then you press. That's it," Jean-Christophe Leroux, senior study author and professor of drug formulation and delivery at ETH Zurich, told Live Science. "If you compare it to microneedles, it is less invasive," he said.

The authors only tested the patch for a short time so would need to find out what would happen if it was used repeatedly. They'd also need to determine which drugs would work with the technology: the target is large molecules, such as those used to treat obesity or osteoporosis, but they can't be too large to fit in the cup, Leroux said.

Chris McConville, an associate professor in pharmaceutics, drug formulation and delivery at the University of Birmingham in the U.K. who was not involved in the research, told Live Science in an email that although the device is interesting, it may not be very practical. The authors tried to mitigate the risk of accidental swallowing of the patch by using dental floss to link it to the volunteer's shirts, for example, but this needs to be further explored.

The authors also used a compound that increases the absorption of drugs called a permeation enhancer with the patch, which could mask any benefits of using it. 

"I am not sure what the device offers over buccal tablets [drugs that stick to the inside of the mouth and dissolve] as it seems that it is the permeation enhancers that increase absorption," McConville said. 

The findings were published Wednesday (Sept. 27) in the journal Science Translational Medicine.

Name: Hoff crab (Kiwa tyleri)

Where it lives: East Scotia Ridge, Southern Ocean

What it eats: Bacteria 

Why it's awesome: It turns out that the Yeti does exist — or at least it does underwater. Named after the abominable snowman, this family of deep-sea squat lobsters was first discovered in 2005. The first example was nicknamed the yeti crab due to the crustacean's white coloration and hairiness. This name was extended to the rest of the family as more species were discovered and described. Later, one hairy-chested species (Kiwa tyleri) was nicknamed "The Hoff" after "Baywatch" actor David Hasselhoff.

But these nicknames are the least-fascinating aspects of this small crustacean. K. tyleri manages to survive in one of the most extreme environments on the planet. In 2010, a remotely operated vehicle dove down to the hydrothermal vents on the East Scotia Ridge in the Southern Ocean and found these yeti crabs densely packed together, with up to 700 individuals per square meter.

Life in these volcanic hydrothermal vents is precarious. The liquid ejected from the vents can reach a scorching 721.04 degrees Fahrenheit (382.8 degrees Celsius), yet not far from the vents, the Antarctic waters are freezing. The crabs must survive in the small area between the two extremes.

Related: The amazing world of Antarctic yeti crabs

Scientists discovered that females with well-developed embryos venture away from the vents. The scalding waters of the hydrothermal vents may not be hospitable for embryonic development, so the females move away and release their larvae into cooler waters. This journey into the cold has a visibly damaging effect on the females, which breed only once before dying.

And what is there to eat in a hydrothermal vent? Not much. But the Hoff crab has found a way to snag grub, and it involves the animal's hairs, known as setae. These setae, which cover the crab's entire belly, harbor bacteria that the crab harvests and eats.

Although they are called yeti crabs, these critters aren't actually true crabs. Instead, they are squat lobsters, and like a number of other decapods, such as king crabs and hermit crabs, they are crab-like. This strange process whereby many different animals end up looking like crabs is a type of convergent evolution known as carcinization.

Name: Hawaiian boxer crab or pom pom crab (Lybia edmondsoni)

Where it lives: The Hawaiian Islands

What it eats: Shrimp, squid 

Why it's awesome: The pom pom crab grows to only around half an inch (13 millimeters) wide, and its soft exoskeleton means its armor is pretty useless. Yet despite its minuscule size, this pugnacious little crustacean likes to fight and eat while clutching dangerous weapons — sea anemones. 

The pom pom crabs, also known as Hawaiian boxer crabs, carry tiny sea anemones in each claw and use them to spar with competitors. This anemone species, Triactis producta, is venomous — and the crabs wave the anemones around as a way of defending against predators and catching food. 

But they also carry them during mini battles with each other. 

In a study of the behavior published in 1997, researchers selected 12 pairs of crabs — six males and six females — and pitted them against each other in a tiny crustacean gladiator arena. The winner was the crab that retreated or fled the least. 

Related: Why do animals keep evolving into crabs?

The videos showed that the crabs used the anemones more for show than for contact. When the anemones did touch opponents, it appeared to be by accident. So why bother wielding these anemones? 

The researchers had lots of ideas, but there was little consensus. There were several proposed (and contradictory) hypotheses. One was that the anemones are so toxic to the crabs that they're too risky to use as weapons — their use could result in severe harm to both fighters. 

On the flip side, they may actually be nontoxic to the crabs, so there's not much point to using them. 

Finally, the anemones may be so valuable that it wouldn't be worth it for the crabs to risk damaging the anemones. They do know the crabs use the anemones to collect food particles and eat from them. When they lose one of the anemones, the crabs split the remaining one in two, so it always has one in each claw.

Scientists are still sorting out why the boxer crabs cling to the sea anemones. What the anemone gets out of it is still unknown. 

In October 1962, the rules of engagement during the Cold War assumed particular urgency. Soviet nuclear warheads were in Cuba — and ships carrying missiles, launchers, and more warheads were on their way. The U.S. needed to establish new rules to communicate with and relate to the Soviet Union. Gregory Bateson, an interdisciplinary scholar, looked to his own studies with octopuses for insight into this problem.

Bateson understood that for birds and mammals, communication was rooted in parent-offspring bonds. In courtship feeding among many bird species, for example, the courted female begs like a young bird and allows the male to feed her. Bateson recognized that the feeding in this context is a signal, because feeding is not its only function. The behavior's additional function is courtship; that is, relationship building. Courtship feeding is a behavioral metaphor, an implicit comparison between one relationship (parental care) enacted as another (courtship).

In the context of the communications between nations, as related by Phillip Guddemi in his 2020 book Gregory Bateson on Relational Communication: From Octopuses to Nations, Bateson looked to another metaphor: that of closeness, physical proximity, which he observed in octopuses. Octopuses were interesting because females tend their eggs, but otherwise lack maternal care of offspring. Octopuses are also notoriously solitary. These facts drew Bateson's attention to their willingness to tolerate the proximity of neighbors as a metaphor for tolerant relationships among nations.

Surprisingly, however, and despite their solitary reputation, octopuses like closeness. Thursday was an octopus that my daughter Laurel and I kept in a home aquarium for a while. Thursday was eager to interact with Laurel. On coming home from school, Laurel would put her fingertips in the water, and Thursday would leave her den at the other end of the tank, scoot along the bottom, and then jet up to the surface for a hello. Even after feeding, she liked to hold on to Laurel, sometimes for as much as a half hour or more. When I chose a seat in the living room to read, Thursday would often quietly relocate in the tank to the point nearest me. She would crawl up and down the glass in my line of sight until I attended to her. By contrast, when Amethyst squirted me with water in the lab, she not only kept me at a distance but also metaphorically indicated her dislike.

Related: Watch an octopus waking up from what scientists think could have been a nightmare

The relational communications in octopuses are not rooted in parental care or mating dynamics. This insight allowed Bateson to wonder how the same mechanisms might serve in the relations of nations. Bateson studied juveniles of either (or both) Verill's two-spot octopus (Octopus bimaculatus) and the California two-spot octopus (Octopus bimaculoides) — he did not always distinguish which. Bateson collected his octopuses along the shores of La Jolla, California, where he at times found two octopuses under a single rock. His experiment similarly consisted of keeping two octopuses in a single tank. The solitary reputation of octopuses makes this a poor idea, and it is seldom done. Indeed, in some cases, one octopus would harass the other persistently, sometimes to death. However, if introduced at the same time, some pairs coexisted. These cases particularly interested Bateson.

Coexistence began with minor battles in which neither octopus was badly injured, a sort of testing phase. The larger octopus stole food from the smaller, and drove it out of shelter. After an interval, the smaller cautiously approached the larger —
a dangerous move — but the larger then retreated. As Bateson saw it, this sequence established trust. First, the stronger octopus demonstrated strength. The weaker then showed its vulnerability by approaching regardless. Finally, and critically, the stronger then held back and refrained from harming the vulnerable octopus, as though showing "I can hurt you but I will not." From this point, the two octopuses could coexist without fighting, and sat in close proximity, sometimes touching.

Armed with these observations, in the final and most tense days of the Cuban missile crisis, Bateson then wrote a remarkable letter, seeking to bring to the attention of the Kennedy administration parallels between the international nuclear crisis and the behaviors of octopuses. The letter was to Bateson's colleague and mentor Warren McCulloch, who Bateson felt could direct the ideas to another colleague in the President’s Science Advisory Committee and thereby reach policy makers within the Kennedy administration.

The Cuban Missile Crisis was resolved within a few days of the letter being written, so there was little time to act on it and no evidence McCulloch ever did. In the near aftermath, however, Bateson remarked that Kennedy had placed "trust" in Khrushchev's judgment, as the quarantine might have given Khrushchev a cause to be offended, but one that the Soviet ruler could decline to act on. That is, Bateson felt that Kennedy's quarantine of Cuba had provoked the Soviets in just the way one octopus could provoke another. The quarantine blocked only weaponry, and fell short of an air strike on the missile sites, or a blockade of Cuba, either of which would have been an act of war. The quarantine provided Khrushchev aggravation not conciliation. Would Khrushchev break the quarantine and land the missiles in Cuba anyway? But six Soviet ships containing weapons stopped short or reversed course before meeting the quarantining U.S. forces. Khrushchev refrained. He subsequently agreed to remove the existing warheads from Cuba. An operational trust had been obtained allowing coexistence.

Bateson's observations were from captive octopuses interacting in pairs, and they described behaviors that remain rare or unheard of in octopuses, such as face-
to-face mating, backing mantle-first toward a rival, and embracing one another after making peace. Out of concern for their welfare, captive octopuses are so seldom housed together that few independent observations exist to expand on Bateson's account. Where we find octopuses together in the wild, they are busily interacting with one another in complex ways. While some of these interactions escalate into battles and can be fatal, most are mediated by relational communication such as signals and low-intensity aggression that fall short of all-out hostility.

Excerpted from Many Things Under a Rock: The Mysteries of Octopuses

The Mysteries of Octopus. Copyright (c) 2023 by David Scheel. Used with permission of the publisher, W. W. Norton & Company, Inc. All rights reserved. 

Incredible footage captures the moment billions of baby crabs risk their lives as they scurry past cannibal adults and swarm the shores of Australia's Christmas Island . 

The ultra-rare video features in "Our Planet II" — David Attenborough's latest Netflix series looking at how animals are adapting to our changing planet — and gives viewers an unprecedented insight into one of the largest congregations of red crablets ever seen. 

The Christmas Island red crab (Gecarcoidea natalis) migration takes place every year, with an estimated 65 million of these crustaceans traveling 1.2 miles (2 kilometers) from the forests where they live on the island to their coastal breeding grounds.

Related: Why do animals keep evolving into crabs?

The migration begins after the first rainfall of the wet season, normally in October or November, according to Parks Australia. When they reach the sea, male crabs dig burrows before being joined by females for mating, with the male transferring sperm for the female to keep in a storage sac. The males then leave, and the females stay behind, producing up to 100,000 eggs each in a brood pouch, an oval-shaped glob attached to the abdomen.

Spawning takes place before dawn during the last quarter of the moon, when females release their eggs into the water as the high tide turns and starts to recede. "The fertilized eggs are dropped into the ocean by the females and hatch on immediate contact with the water," Lucy Turner, a marine biologist at the University of Plymouth, U.K. who was not involved with the video, told Live Science in an email. 

Over the course of a month, after going through different larval stages, the baby crabs — or crablets — eventually develop into little creatures known as megalopae. 

In the new clip from "Our Planet II," viewers see the crablets' return to dry land. As they emerge from the water, they shed their waterproof shells to become fully formed crabs at just 0.2 inch (5 millimeters) across. 

But as they get to the beach, danger is lurking. An adult crab stands waiting, picking the tiny crablets up with its claws and eating them. 

"These crabs are opportunistic scavengers so will feed on anything," Turner said. "I have never seen this behavior before though, where they are cannibalistic of juveniles. I've seen them eat other dead adults."

This cannibalistic behavior is particularly surprising as adult red crabs are usually not aggressive so would not actively hunt one another, said Simon Webster, a zoologist at the U.K.'s Bangor University who was not involved with the footage. "They certainly need to feed on their migration," Webster told Live Science in an email. "When they finish their migration, the glycogen levels in their muscles are extremely low, so anything they can eat, they will!" 

He added red crabs will also feast on dead, squashed crabs if they find them on the road. 

Only a small percentage of Christmas Island red crablets make it to the forest. Many are killed before they even leave the ocean. "We don't have exact numbers for this but based on other crabs with a marine larval phase we estimate that less than 10%, and it could be as few as 1% reach the shore, and similarly reach adulthood," Turner said. 

What happens when they reach the forest is unknown. "The small crabs just seem to vanish into the rainforest," Webster said. "It has been suggested they occupy old, unused burrows, and it is thought that they stay in the rainforest … for their early life, but essentially, this is still somewhat of a mystery."

"Our Planet II" will be available to stream exclusively on Netflix from June 14.

As the seasons change, octopuses rewire their brains to adapt to fluctuating ocean temperatures, a new study finds. 

Octopuses and other cephalopods are cold-blooded, or ectothermic, meaning they cannot internally regulate their body temperature. As a result, they are vulnerable to external temperatures in the water, which can threaten the brain function of these exceptionally intelligent creatures if the water gets too cold or too hot. 

To prevent this, California two-spot octopuses (Octopus bimaculoides) edit their RNA — the messenger molecule between DNA and proteins — to produce different neural proteins in response to varying temperatures, according to the study, which was published Thursday (June 8) in the journal Cell. Led by researchers at the Marine Biological Laboratory in Woods Hole, Massachusetts, the study focuses on messenger RNA, which acts as a messenger for the instructions encoded in DNA and carries that transcribed genetic information to the protein-building factories, or ribosomes, in cells.

Related: Octopuses may be so terrifyingly smart because they share humans' genes for intelligence

During the study, scientists gathered 12 wild-caught California two-spot octopuses — a yellowish-brown species known for its two iridescent blue false eyes — and split them into two groups based on different test conditions: a warm tank with water that was 71 degrees Fahrenheit (22 degrees Celsius) and a cold tank with water that was 55 F (13 C). After several weeks, the researchers compared the RNA transcripts of the octopuses in the warm tanks to the ones in the cold. 

They expected to see changes in the RNA at only a few sites. Instead, they discovered changes at more than 20,000 of the 60,000 sites they looked at. And these RNA edits started happening within a matter of hours after the octopuses were exposed to new temperatures, the researchers found. 

"The beauty of RNA editing is that, on one hand, you change the genetic information and it's quite fluid, and on the other hand, you will keep the DNA intact," study co-author Eli Eisenberg, a genetics researcher at Tel Aviv University in Israel, told Live Science. "That's a nice thing that you can edit the RNA according to the needs of the present environment." 

For the next part of their study, they worked with researchers at the University of Michigan and Texas Tech University to determine whether these RNA changes actually affected protein structure. To do so, they compared the edited and unedited versions of two proteins in the octopuses that are crucial for nervous system function: kinesin, which are associated with cell membranes, and synaptotagmin, a calcium-binding protein. 

They found evidence confirming that temperature-driven changes in the RNA translated into structural changes in kinesin and synaptotagmin — and that these changes would also affect the proteins' function, likely in a way that makes the octopuses better adapted to the chilly or warm waters they are operating in. 

"One could say that [many of] the proteins that the octopus uses in the winter are not the same as the ones it uses in summer," Eisenberg said. A 2012 study showed differences in the RNA of different octopus species living in a variety of warm and cold environments, but this is the first research to show RNA editing happening in one octopus species in response to real-time changes in temperature, the researchers said. 

For many species, RNA editing has little or no effect on an individual because it happens in regions of the DNA that do not code for anything. For example, humans have millions of RNA editing sites, but only 3% of these affect proteins' structure. In octopuses, RNA editing affects the majority of their neural proteins, and now scientists know that these sophisticated cephalopods use this ability to acclimate to warm and chilly waters. 

The researchers also found evidence that the Verrill's two-spot octopus (Octopus bimaculatus), a closely related relative, also had temperature-sensitive RNA, suggesting that this phenomenon may be widespread among octopuses and squid.

"At the end of the day, we know very little about [cephalopods]," said Michael Kuba, an ecologist who specializes in cephalopods at the University of Naples in Italy and who was not involved in the study. "This paper is just an extremely important first step to really understand more how they deal with the environment," he told Live Science.

Eisenberg and his team are now working on further research to determine whether RNA editing is helping octopuses adapt to other environmental conditions, such as low-pH (acidic) or low-oxygen ("hypoxic") areas, which could become more common as climate change accelerates. 

A flat, rounded shell. A tail that's folded under the body. This is what a crab looks like, and apparently what peak performance might look like — at least according to evolution. A crab-like body plan has evolved at least five separate times among decapod crustaceans, a group that includes crabs, lobsters and shrimp. In fact, it's happened so often that there's a name for it: carcinization.

So why do animals keep evolving into crab-like forms? Scientists don't know for sure, but they have lots of ideas.

Carcinization is an example of a phenomenon called convergent evolution, which is when different groups independently evolve the same traits. It's the same reason both bats and birds have wings. But intriguingly, the crab-like body plan has emerged many times among very closely related animals. 

The fact that it's happening at such a fine scale "means that evolution is flexible and dynamic," Javier Luque, a senior research associate in the Department of Zoology at the University of Cambridge, told Live Science.

Related: Does evolution ever go backward?

Crustaceans have repeatedly gone from having a cylindrical body plan with a big tail — characteristic of a shrimp or a lobster — to a flatter, rounder, crabbier look, with a much less prominent tail. The result is that many crustaceans that resemble crabs, like the tasty king crab that's coveted as a seafood delicacy, aren't even technically "true crabs." They've adopted a crab-like body plan, but actually belong to a closely related group of crustaceans called "false crabs."

When a trait appears in an animal and sticks around through generations, it's a sign that the trait is advantageous for the species — that's the basic principle of natural selection. Animals with crabby forms come in many sizes and thrive in a wide array of habitats, from mountains to the deep sea. Their diversity makes it tricky to pin down a single common benefit for their body plan, said Joanna Wolfe, a research associate in organismic and evolutionary biology at Harvard University.

Wolfe and colleagues laid out a few possibilities in a 2021 paper in the journal BioEssays. For example, crabs' tucked-in tail, versus the lobster's much more prominent one, could reduce the amount of vulnerable flesh that's accessible to predators. And the flat, rounded shell could help a crab scuttle sideways more effectively than a cylindrical lobster body would allow.

But more research is needed to test those hypotheses, Wolfe said. She is also trying to use genetic data to better understand the relationships among different decapod crustaceans, to more accurately pinpoint when various "crabby" lineages evolved, and pick apart the factors driving carcinization.

There's another possible explanation: "It's possible that having a crab body isn't necessarily advantageous, and maybe it's a consequence of something else in the organism," Wolfe said. For example, the crab body plan might be so successful not because of the shell or tail shape itself, but because of the possibilities that this shape opens up for other parts of the body, said Luque, who is a co-author of the 2021 paper with Wolfe.

For example, a lobster's giant tail can propel the animal through the water and help it crush prey. But it can also get in the way and constrain other features, Luque said. The crab body shape might leave more flexibility for animals to evolve specialized roles for their legs beyond walking, allowing crabs to easily adapt to new habitats. Some crabs have adapted their legs for digging under sediment or paddling through water.

"We think that the crab body plan has evolved so many times independently because of the versatility that the animals have," Luque said. "That allows them to go places that no other crustaceans have been able to go."

The crab-like body plan also has been lost multiple times over evolutionary time — a process known as decarcinization.

"Crabs are flexible and versatile," Luque explained. "They can do a lot of things back and forth."

Wolfe thinks of crabs and other crustaceans like Lego creations: They have many different components that can be swapped out without dramatically changing other features. So it's relatively straightforward for a cylindrical body to flatten out, or vice versa. But for better or worse, humans won't be turning into crabs anytime soon. "Our body isn't modular like that," Wolfe said. "[Crustaceans] already have the right building blocks."

Scientists have filmed an octopus exhibiting strange behaviors in a laboratory in New York that could be explained by it having nightmares. Over the course of a month, researchers watched as the octopus appeared to jolt out of a restful sleep and thrash around, in a behavior that seemed almost like the animal was suffering from some kind of sleep disorder.

But was this octopus really having nightmares? There are some other potential explanations for why the animal might have acted this way, and experts expressed caution in interpreting the animal's behavior too quickly – but nonetheless, this behavior is certainly unusual. 

"For all the studies that have been done" on octopuses and other cephalopods, "there’s still so much we don't know," said Eric Angel Ramos, a postdoctoral researcher at the University of Vermont who helped film the octopus.

Video footage from a laboratory at The Rockefeller University in New York captured four episodes in which an Octopus insularis named Costello appeared to sleep calmly in a tank before suddenly flailing its tentacles around in a frenzy. In two of these instances, Costello also shot a jet of black ink into the water, a common predator-defense mechanism. 

Related: Octopuses torture and eat themselves after mating. Science finally knows why.

"It was really bizarre, because it looked like he was in pain; it looked like he might have been suffering, for a moment," Ramos told Live Science. "And then he just got up like nothing had happened, and he resumed his day as normal."

Some of these behaviors are similar to what an octopus might do when encountering a predator in the wild, according to the research team, who described these behaviors in a preprint (which has not been peer-reviewed) posted to the server bioRxiv this month. 

That led the authors to speculate that “the animal may have been responding to a negative episodic memory or exhibiting a form of parasomnia,” meaning a sleep disorder. But they also cautioned that nothing can be definitively concluded from these observations.

Recently, researchers have learned more about octopus sleep. In 2021, scientists published a study documenting evidence of a two-stage sleep pattern in the animals, consisting of “active” and “quiet” sleep — similar to how humans fluctuate between rapid eye movement (REM) and non-REM sleep each night. In humans, most dreaming occurs during REM sleep, so some scientists have wondered if octopuses may also dream during their “active” sleep stage.

However, one expert who wasn’t involved in the observations expressed caution in interpreting the octopus's actions as dreams.  

We don't know enough about the neuroscience of sleep in cephalopods to know if they dream at all, let alone have nightmares, Robyn Crook, a comparative neurobiologist at San Francisco State University, told Live Science. And even if octopuses do dream, they might dream in a completely different way than humans do, she said.

“It's not something that we could easily answer,” Crook said. “It's a very philosophical question.”

So although the behaviors in this video are "very interesting," they could very likely have been spurred by something other than dreams, she said. 

For example, the octopus might have just been startled by something, Crook said. This octopus also might have been exhibiting signs of senescence, she said. This is the stage of an octopus’s life that occurs right before death, when their bodies start to break down. 

In another octopus species, the giant Pacific octopus (Enteroctopus dofleini), Crook and her colleagues recently found an association between senescence and nervous system degradation. To her, the arm movements in the video seemed more like evidence of a lack of motor control,  which she says is associated with senescence, rather than anti-predator behavior.

Indeed, the species Costello belongs to lives for about 12 to 18 months, Ramos said, and Costello died shortly after these incidents. "I don't exclude that senescence could be one of the drivers of this," he told Live Science. 

It's possible that this behavior seemed unusual because many laboratory octopuses are euthanized before they start to senesce, Ramos said. Plus, most labs aren't filming their octopuses 24/7, he added, so other laboratories might have missed chances to spot similar behaviors.

Octopuses possess a brain wave that has never been seen before in animals, along with others similar to those found in humans, first-of-their-kind brain recordings reveal. 

The groundbreaking study captured the first ever brain recordings of freely moving octopuses and was performed by implanting electrodes in the animals’ brains and connecting them to data loggers under their skin. The recordings have given scientists the very first inklings into the workings of cephalopod minds. The researchers published their findings March 27 in the journal Cell.

"Some of these activity patterns have some similarity to activity patterns observed in the mammalian hippocampus, also a memory center," first-author Tamar Gutnick, a visiting scientist at the University of Naples, told Live Science. "But we also observed unique patterns, 2Hz activity, that were never reported in other animals."

Related: Octopuses may be terrifically smart because of this genetic quirk they share with humans

Octopuses and their close cephalopod relatives, such as squid and cuttlefish, have been a subject of fascination among biologists ever since the third century A.D., when Roman author and naturalist, Claidius Aelianus, noted their "plainly seen" characteristics of "mischief and craft." 

Octopuses and other cephalopods have long been studied because of their intelligence. The animals possess remarkable memories, excel at camouflage; are curious about their surroundings, have been observed using tools to solve problems, and — as the ripples of colors that flash across their skin as they sleep indicate — are even thought to dream.  

However, octopuses’ minds can be difficult to peer into. The creatures’ arms can reach to any part of their boneless bodies, so not only can they easily snatch and detach any invasive tracking object, but there is no obvious place in which to anchor recording devices that can detect brain waves. 

To get around this, the researchers surgically inserted medical tracking devices into the heads of three captive octopuses, placing lightweight data loggers often used on birds between their eyes before connecting them to electrodes inserted into a region of the octopuses’ brains responsible for learning and memory. The scientists then recorded the octopuses for 12 hours as the creatures slept, groomed themselves and explored their tank.

The recorded brain wave patterns surprised the scientists in a number of ways. First of all, the researchers discovered brain waves that were very similar to those found in the human hippocampus. 

This hints at convergent neurological evolution — where two separate animals evolve the same trait independently of each other — as humans’ last common ancestor with octopuses was a seafloor-trawling flatworm that lived around 750 million years ago and did not possess anything other than a rudimentary brain. The researchers also found brain waves known for controlling sleep-wake cycles in other animals.

Alongside the more familiar brain waves, the researchers also found ones they had never seen before in the recordings; long-lasting and slow, they repeated just twice every second. Scientists aren’t sure what these mysterious brain waves are being used for, and it will take more recordings while octopuses complete set tasks to fully map them, the researchers said.

"Most likely they all require recordings on octopuses that are trained to show certain behaviors, so that we can get several repetitions with similar behavior," Gutnick said. "In vertebrates, this is the key to finding patterns in brain activity that help us to understand how the brain coordinates behavior."

Scientists in Hong Kong have discovered tiny, cube-shaped box jellyfish in a brackish shrimp pond that are completely unknown to science.

The diminutive jellies have a completely transparent and colorless body, or bell, as well as 12 tentacles ending in small, paddle-like structures that enable the critters to speed through water faster than most other jellyfish species. 

Like other box jellies — a group of Cnidarians that includes the Australian box jellyfish (Chironex fleckeri), the world’s most venomous marine animal, according to the National Ocean Service — the newly described jellies have 24 eyes arranged in clusters of six around its cubic bell.

"This box jellyfish connects the base of its tentacles and its bell with a flat base that looks like a boat paddle, making it distinct from other common jellyfish," Qiu Jianwen, a professor in the Department of Biology at Hong Kong Baptist University who led the research, said in a video. "Another feature of the box jellyfish is that it has six eyes located on each side of its body." 

Researchers named the newfound species Tripedalia maipoensis after Mai Po Nature Reserve in Hong Kong, where they found it. They describe its features and relationship to other box jellies in a study published March 20 in the journal Zoological Studies.

Related: Alien-like giant phantom jellyfish spotted in frigid waters off Antarctica 

T. maipoensis is the first-ever box jelly to be found in Chinese waters. It is unclear whether the half-inch-long (1.5 centimeters) animal can sting humans, but it may be venomous enough to stun tiny shrimp called Artemia. "It seemed to paralyze Artemia offered in the lab," Qiu told Live Science in an email. "But we did not touch the animal to feel the sting."

The researchers first noticed the unusual creatures in samples collected from an intertidal shrimp pond, known as a "gei wai" locally, during the summers of 2020 to 2022. The jellyfish were "quite abundant," Qiu told Live Science, numbering "up to 400 individuals in an area of the pond." A tidal channel from the brackish pool means that the species could also be present in the adjacent waters of the Pearl River estuary, but no work has been done yet to confirm this, the researchers wrote in the study.

Box jellyfish, which are also known as sea wasps, move by allowing water to enter canals that run along a muscular membrane on the underside of their bodies and then expelling it. The researchers found that, unlike closely related species, T. maipoensis has forked canals separating into multiple branches. The newly discovered species is the third known member of a group of box jellies characterized by tentacles ending in flat, paddle-like structures, called Tripedalia. 

The scientists also noted that each cluster of six eyes on the jellies' cubic bell includes a pair of eyes with lenses that enable image-forming, as well as four eyes that can only sense light.

The species probably feeds on small crustaceans called copepods, which were abundant in the samples taken from the shrimp pond, Qiu told Live Science.

"We are thrilled with this discovery," Qiu said in the video. "Finding a new species in Mai Po, where extensive research has been conducted, highlights the potential for more marine life discovery in the Hong Kong and even the Chinese coastal waters."

Octopuses are iconic for their eight arms. But how many hearts does an octopus have?

It turns out that an octopus has three hearts, Kirt Onthank, an octopus biologist at Walla Walla University in Washington, told Live Science. The same holds true for their closest relatives, squid and cuttlefish.

The octopuses' largest heart, the systemic heart, is located in the middle of the mollusk's body. It pumps oxygenated blood around the body, but not to the gills. "It is the largest and most muscular of the three hearts," Onthank said.

The other two hearts are called the branchial hearts, each of which is attached to one of the octopus's two gills, "so they are often called the 'gill hearts,'" Onthank said.

Each branchial heart's job is to pump blood through the gill it is attached to. "These hearts are relatively small and not especially strong," Onthank said.

Related: How do octopuses change color?

So why does an octopus need three hearts? "The same reason that humans and other mammals need four chambers in their hearts — solving the problem of low blood pressure," Onthank explained.

Animals need enough blood pressure to deliver blood throughout their bodies effectively. If a person suffers from low blood pressure, "they can get lightheaded or even pass out if they stand up too fast or exert themselves," Onthank noted. "This is because the low pressure isn't sufficient to deliver blood to the brain."

Octopus gills help draw in vital oxygen from the water, and the branchial hearts help pump oxygen-poor blood through the gills. However, the oxygen-rich blood that emerges from the gills comes out at low pressure, "which is not good for sending blood to the body," Onthank said. So octopuses "have another heart after the gills to pressurize the blood again so that it can be sent to the body efficiently," he explained.

Humans have a similar problem. The right two chambers of the heart — the right atrium and the right ventricle — pump oxygen-poor blood from the veins into the lungs. When oxygen-rich blood leaves the lungs, it comes out at low pressure, Onthank said.

However, humans then send this oxygen-rich blood back to the heart — specifically, to the left two chambers: the left atrium and the left ventricle. These chambers repressurize the blood and send it through the arteries to the rest of the body. 

In other words, octopuses and humans solve the same problem in two very different ways: octopuses by having multiple hearts, and humans by having a heart with multiple chambers.

"In the end, those three hearts are accomplishing the same task that your four-chamber heart does," Onthank said. "Octopuses are a great example of how a complex, intelligent organism could evolve in a completely separate lineage from vertebrates. They have the same problems but have hit on different solutions."

Intriguingly, a 1962 study suggested that the systemic heart of the giant Pacific octopus (Enteroctopus dofleini) might totally stop "for long periods of time when they are resting, when they don't need high blood pressure as much," Onthank said. Instead, "the gill hearts do all the work."

In addition, octopus hearts stop for a few moments when they swim, and no one is certain why, Onthank said.

"I think the best explanation is that swimming puts such high pressure on their hearts that it is better just to stop them for a few moments while swimming rather than try to pump against that pressure," Onthank said.

Octopuses swim by squirting jets of water from their bodies.

"It is a bit like filling up a balloon and releasing it to let it fly around," Onthank said. This puts a lot of pressure on their bodies, which may prevent their hearts from pumping properly. "So rather than fighting that pressure, they may just hit the pause button on their hearts for a moment or two," he added.

Octopuses generally prefer crawling to swimming. "Really, swimming for octopuses is kind of a mess," Onthank said. "They blow themselves forward with the same stream of water they breathe with, so swimming messes with their breathing as well. With swimming stopping their hearts for a few moments and messing with their breathing, it isn't surprising they don't swim that much."

Blue, copper-based blood

Another way in which the octopus circulatory system differs from that of humans is how their blood is blue. This is because octopuses and their cephalopod relatives use copper-based proteins called hemocyanins to carry oxygen in their blood, instead of the iron-based protein called hemoglobin that humans do.

Hemocyanins are less effective than hemoglobin at binding to oxygen at room temperature. One might then naively think this might be a reason why the octopus needs three hearts. However, hemocyanins carry more oxygen than hemoglobin in low-oxygen environments and at low temperatures, which make them more useful at sea, Onthank said.

In addition, when octopus hemocyanin binds to one oxygen molecule, that makes it more likely to glom onto another. This property, called cooperativity, makes it much better at oxygen transport than most hemocyanins, Onthank said.

All in all, in the sea, octopus hemocyanin "is at least a comparable, if not better, oxygen transport pigment than hemoglobin," Onthank said. "Now if we are thinking about whether octopuses could conquer land, then hemocyanin would likely hold them back."

Rare sightings of giant phantom jellyfish — deep-sea creatures that look like UFO spaceships with thick ribbons streaming from their undersides — have been reported by cruise liner passengers who spotted the otherworldly animals off the coast of Antarctica, a new study finds. 

The giant phantom jellyfish (Stygiomedusa gigantea), one of the deep sea's largest invertebrate predators, met the guests while they were riding in a submersible deployed by cruise line operator Viking in early 2022. Researchers estimated that the jellyfish were longer than 16 feet (5 meters), with one stretching to at least 33 feet (10 m) in length, according to a study published Jan. 30 in the journal Polar Research. 

Study first author Daniel Moore first realized guests had encountered the giant phantom when he saw a picture of one on a guest's camera. "I instantly recognised it for what it was and, given the rarity of sightings, was flooded with excitement," Moore, one of Viking's chief scientists, told Live Science in an email. 

Related: Largest crown jellyfish ever discovered is a blood red, saucer-like weirdo

Giant Phantom jellyfish live in every ocean except for the Arctic Ocean. However, because these cryptic creatures typically swim deep below the surface, they are scarcely seen by humans. The new study describes direct observations of three different jellyfish made during submersible dives off the Antarctic Peninsula.

"On every sighting the jellyfish appears to be swimming slowly, gently pulsing its bell for propulsion," Moore said. "They don't appear to have shown any inclination towards the lights of the submersible or reaction to our presence."

The jellyfish were spotted at depths of 260 feet (80 m), 285 feet (87 m) and 920 feet (280 m). Giant phantom jellyfish primarily occupy depths of below 3,280 feet (1,000 m), but they are encountered higher up in the Southern Ocean, or Antarctic Ocean. It's not yet known why they hang out in relatively shallow waters around Antarctica.

Moore noted that one potential explanation is that the jellyfish swim higher up to expose themselves to ultraviolet radiation, which will rid them of parasites. Another hypothesis put forward by Moore is that the upwelling deep water found around the Antarctic continent simply carries them upward. Moore hopes that their observations will lead to a better understanding of giant phantom jellyfishes' lives. 

The practice of cruise lines taking passengers to Antarctica has attracted some controversy. The U.S. Coast Guard announced on Feb. 2 that it has joined international partners to investigate four deaths and other casualties involving U.S. citizens on Antarctic passenger vessels between Nov. 15 and Dec. 1, 2022. This includes one death on the Viking Polaris, operated by Viking, after a large wave hit the ship.

The U.S. Coast Guard describes the Antarctic as a "unique high-risk" environment and aims to improve marine safety and prevent similar incidents in the future. The waters around Antarctica can be treacherous and the continent has a history claiming intrepid explorers in famous expeditions. 

A gorgeous new image shows a common sea dragon dad drifting through a seagrass meadow with his jewel-like egg clutch in tow. 

The image took the top spot in the Compact Behavior category of the Underwater Photography Guide's 2022 Ocean Art contest.

Common sea dragons (Phyllopteryx taeniolatus) typically live at depths of around 13 to 20 feet (4 to 6 meters), though they can dive down to 160 feet (50 m), according to the Georgia Aquarium. They usually begin brooding in late July or early August. 

The eggs start out a beautiful shade of deep magenta, which fades to brown as the baby dragons develop. Sometimes green or brown algae grows along the dad's tail, helping provide further camouflage. "After a few weeks, you start to see eye spots inside each [egg]", Greg Rouse, a marine biologist at the University of California San Diego's Scripps Institution of Oceanography who wasn't involved with the photo contest, told Live Science. Rouse said that the eggs pictured here are "a pretty fresh brood."

Unlike most vertebrates, male sea dragon parents are the ones who invest time and energy into caring for unhatched eggs. Closely related groups, including seahorses and pipefishes, also display this unusual brooding strategy. However, seahorses and some pipefish sport a specialized kangaroo-like pouch to hold their eggs, whereas sea dragons simply glue their eggs to the underside of their tails. A clutch of sea dragon eggs typically numbers somewhere between 100 and 180, depending on the size of the female.

Related: Best wildlife photography cameras 2023

All sea dragons are endemic to the waters of coastal Australia. They're notoriously tricky to breed in captivity: Of the three species of sea dragon, only the common (or weedy) dragon has been successfully captive-bred, and not in large enough numbers to sustain a sizable population. "The sea dragons people see in the aquarium are mostly being caught in the wild," Rouse said. To help monitor how this impacts sea dragon numbers, Rouse co-founded the citizen science project Seadragon Search, in which diving enthusiasts can record their encounters with these fish.

Sea dragon dads are far from the only extreme marine parents, and Ocean Art's other parent of the year is a mother octopus. In a stunningly detailed photo that earned best in show, the octopus mom holds her brood carefully in her eight arms, gently wafting water over them to make sure the developing babies get enough oxygen. The photographer identified her as a Caribbean reef octopus (Octopus briareus) and snapped this photo in the balmy waters off of West Palm Beach, Florida. 

"For warm water [octopus] species, the eggs develop pretty quickly. But for colder species they take a lot longer," Mike Vecchione, a cephalopod zoologist with the National Oceanic and Atmospheric Administration who wasn't involved with the photo contest, told Live Science. Researchers from the Monterey Bay Aquarium Research Institute discovered a female deep-sea octopus that held onto her eggs for four years — the longest known brood duration for octopuses. 

The octopus pictured here won't have to wait that long for her eggs to hatch. However, keeping them safe will be the last thing she does. Mother octopuses don't eat or care for themselves while protecting their brood from predators. "They're in pretty bad condition by the time the eggs hatch," said Vecchione, "and as far as we know, they all die shortly after that."

Scientists who watched nerve cells connect inside the eyes of growing squid have uncovered a remarkable secret — the cephalopods’ brains independently evolved to develop in the same way ours do.

The discovery, made using high-resolution cameras focused on the retinas of longfin squid (Doryteuthis pealeii) embryos, reveals that, in spite of 500 million years of divergent evolution, the basic blueprint for how complex brains and nervous systems evolve may be the same across a wide range of species. 

The intelligence of cephalopods — a class of marine animals that includes octopuses, squid and cuttlefish — has long been a subject of fascination among biologists. Unlike most invertebrates, these animals possess remarkable memories; use tools to solve problems; excel at camouflage; react with curiosity, boredom or even playful malevolence to their surroundings; and can dream, if the ripples of colors that flash across their skin as they sleep are any indication. 

Now, this new study, published Dec. 5, 2022 in the journal Current Biology, suggests that key parts of the formula for advanced intelligence, on Earth at least, remain the same.

Related: Octopuses may be so terrifyingly smart because they share humans' genes for intelligence

"Our conclusions were surprising because a lot of what we know about nervous system development in vertebrates has long been thought to be special to that lineage," study senior author Kristen Koenig, a molecular biologist at Harvard University, said in a statement. "By observing the fact that the process is very similar, what it suggested to us is that these two [lineages] independently evolved very large nervous systems using the same mechanisms to build them. What that suggests is that those mechanisms — those tools — the animals use during development may be important for building big nervous systems."

To study the squid embryos’ developing brains, the scientists used fluorescent dyes to mark a special type of stem cell called neural progenitor cells, before studying how they developed with regular, 10-minute snaps from microscope cameras. The cameras looked at the retinas, where roughly two-thirds of a squid's neural tissue is found.

Just as in vertebrates, the researchers saw the squids’ progenitor cells arrange themselves into a structure called a pseudostratified epithelium — a long, densely packed structure that forms as a crucial step in the growth of large, complex tissue. The researchers noted that the size, organization and movement of the structure's nucleus was remarkably similar to the same neural epitheliums in vertebrates; something that was once considered a unique feature that enabled back-boned animals to grow sophisticated brains and eyes.

This is not the only time that scientists have spotted cephaolopods sharing common neurological blueprints with us. Much like humans, octopuses and squid also have a large variety of microRNAs (small molecules that control how genes are expressed) found inside their neural tissue.

Next, the team wants to look at how and when different cell types in the squid emerge as tissue grows and compare this process to the one observed in vertebrate embryos. If the blueprint for growth is the same, then perhaps the timetable could be, as well.

"One of the big takeaways from this type of work is just how valuable it is to study the diversity of life," Koenig said. "By studying this diversity, you can actually really come back to fundamental ideas about even our own development and our own biomedically relevant questions. You can really speak to those questions."

Octopuses may have gained some of their exceptional intelligence from the same evolutionary process that humans went through, a new study suggests. 

The process involved a sudden explosion of microRNAs (miRNAs) — small, noncoding molecules that control how genes are expressed. This increase may have helped the brains of octopuses and humans to develop new types of nerve cells, or neurons, which were stitched together into more complex neural networks. 

Octopuses and their close cephalopod relatives, such as squid and cuttlefish, have been a subject of fascination among biologists ever since the third century A.D., when Roman author and naturalist, Claidius Aelianus, noted their "plainly seen" characteristics of "mischief and craft." Octopuses possess remarkable memories; excel at camouflage; are curious about their surroundings; have been observed using tools to solve problems; and, from the ripples of colors that flash across their skin as they sleep, are even thought to dream. 

Related: Octopuses may be so terrifyingly smart because they share humans' genes for intelligence

But the exact foundation for how their minds evolved such complexity independently from our own remains a fascinating puzzle. Humans’ last common ancestor with octopuses, for example, was a seafloor-trawling flatworm that lived around 750 million years ago, and did not possess anything other than a rudimentary brain. One recent study found that jumping genes, known as transposons, could account for some of Octopuses’ smarts. Now, a new study published Nov. 25 in the journal Science Advances might have found another important piece of the puzzle.

"If you want to find out about the intelligence, or the brains, of an alien, a good model for that is studying the octopus," study senior author Nikolaus Rajewsky, a systems biologist at the Max Delbrück Center for Molecular Medicine in Berlin, Germany, told Live Science. "The evolution of its complex brain, and the cognitive features that come with it, happened completely independently from us. So by comparing it to us, you can learn about general features shared between us, but you can maybe also find stuff that the octopus has that we don't." 

The researchers studied 18 different tissue types taken from dead common octopuses (Octopus vulgaris), analyzing their RNA and comparing it to the RNA belonging to other cephalopods such as the California two-spot octopus (Octopus bimaculoides) and the bobtail squid (Euprymna scolopes), as well as more distant relatives such as the nautilus and cnidarians.

RNA is a single-stranded length of genetic code that gets transcribed from DNA to make proteins within cells, and is sometimes involved in regulating gene expression. Initially, the scientists believed that octopuses were using specially evolved enzymes to edit their DNA for greater neuronal complexity, but what the tissue analysis revealed instead was a historical explosion in the number of different miRNAs conserved across multiple species of cephalopods; a number comparable with those found in some vertebrates, such as humans.

microRNAs are tiny chunks of RNA that bind to protein-coding RNA strands, regulating their activity and silencing the expression of certain genes. This enables the genome to be more finely tailored to specific purposes, creating new types of brain cells that can be chained into more elaborate neural webs. The researchers found a whopping 51 new miRNAs families conserved across octopuses and squids since their ancestral lineages split more than 300 million years ago, and octopuses alone gained 90 since their last common ancestor with other molluscs such as oysters — which had acquired only five.

"This is just spectacular," Rajewsky said. "Octopus microRNA numbers shoot up to reach levels comparable to those of complex vertebrate brains."

The researchers also found that the octopus miRNAs are expressed most prevalently in nervous tissues in the developing brains of octopus hatchlings — a strong suggestion that the RNA regulators are driving the development of more complex cognitive abilities.

The researchers stress that a direct link between miRNA numbers and advanced intelligence is not yet directly proven, and that to establish this link scientists will need to complete a follow-up study into the cell types that the novel miRNAs are enriched in. By doing so, the scientists hope to not only find the things we share with the alien brains of octopuses but also unearth parts of the octopus genome that could be used to develop better tools for editing our own.

"This is not, I think, totally crazy, because many things have been discovered like this," Rajewsky said. "For example, CRISPR-Cas9 doesn't exist in our genome, but bacteria have it and so you now can use it to edit our own."

Sea-Monkeys is the marketing term for a common type of sea creature: brine shrimp. As a product, Sea-Monkeys were first sold in 1950s. Sea-Monkeys are sold in packets of dust comprised of brine shrimp eggs in suspended animation. The process used to create these creatures is proprietary.

Despite their name, they're not monkeys. Sea-Monkeys are a hybrid breed of brine shrimp called Artemia NYOS produced in 1957 by Harold von Braunhut, according to the journal American Entomologist. Initially marketed as "Instant Life," Sea-Monkeys are sold in hatching kits as novelty aquarium pets. 

The inspiration behind Sea-Monkeys came from a trip to a pet store, according to the Sea-Monkeys website. Von Braunhut saw brine shrimp being used as fish food and wondered whether they could be used to teach children about nature. He conducted experiments to find ways to preserve the brine shrimp and then bring them back to life. 

According to EMBO Reports, the creatures, which have vaguely monkey-like tails that inspire the moniker, are derived from crustaceans that undergo "cryptobiosis." Cryptobiosis is a state of suspended animation that some creatures, such as tardigrades, can enter in times of adverse environmental conditions. Creatures can stay in this state indefinitely, then reanimate when conditions improve.

When a person buys a packet of Sea-Monkeys, they appear to be lifeless dust. But when the dust is put into a tank of purified water, the Sea-Monkeys gradually emerge. They grow steadily over the next few weeks, feeding on a diet of yeast and spirulina, according to the Microscopy Society of America (MSA).

Sea-Monkeys are born with one eye, and pop out two more upon reaching maturity, according to the journal Evolutionary Biology. They're translucent, and breathe through their feathery feet. They can reproduce sexually or asexually, and they chase flashlight beams. 

Although Sea-Monkeys are not found in nature, other brine shrimp are. Artemia NYOS are a hybrid of Artemia salina, according to the book Reproductive Biology of Crustaceans. 

Artemia salina live in highly salty environments, such as brine pools, according to Encyclopaedia Britannica. They display similar leaflike limbs to Sea-Monkeys, which they beat to move. When they are freeze dried, Artemia salina eggs can last for several years, according to the book Medicinal Plant Research in Africa. 

Additional resources

You can read more about brine shrimp in this publication by the British Ecological Society. Additionally, for tips about looking after Sea-Monkeys, read the Sea-Monkey Handbook. 

It's no wonder that, with so many arms, octopuses turn out to be great pitchers. They can even target other octopuses with bits of seafloor debris — and score a direct hit.

For the first time, researchers have observed the famously brainy cephalopods deliberately hurling clumps of sand, bits of algae and even shells at each other, though they don't actually toss with their arms as people do. Rather, they use their arms to gather projectiles and then propel them using jets of water expelled from a siphon under their arms. Scientists captured video footage of this unusual behavior in gloomy octopuses (Octopus tetricus) in Jervis Bay on the southern coast of New South Wales in Australia and described their findings Nov. 9 in the journal PLOS One.  

"In some cases the projected material hits another octopus, or another object (a fish or a camera)," the scientists wrote in the study. 

After examining 24 hours of footage recorded on stationary underwater cameras in 2015 and 2016, the study authors identified 102 examples of about 10 octopuses picking things up and throwing them. Often, the objects flew up to several body lengths away from the thrower.

"Doing this underwater, even for a short distance, seems especially unusual and quite hard to do, making this an even more striking behavior," study co-author David Scheel, a professor of marine biology at Alaska Pacific University in Anchorage, told Live Science in an email.

The octopus behavior that scientists captured on video is unusual for animals — just a few types of social mammals are known to throw things at each other, the researchers reported (footage credit: Godfrey-Smith et al., 2022, PLOS ONE, CC-BY 4.0).

Related: Octopuses may be so terrifyingly smart because they share humans' genes for intelligence

Both male and female octopuses would throw debris, though two females performed about 66% of all the throwing. As for what motivated the octopuses to start hurling debris, around 32% took place while the octopuses were cleaning their dens. But 53% of the silt chucking happened during an interaction with another octopus, a fish or one of the cameras. 

Other octopuses got pelted by the lobbed debris in 17 cases. In some incidents, the target would raise an arm right before a missile launched, "perhaps in recognition of the act in preparation," the scientists wrote. "Octopuses in the line of fire ducked, raised arms in the direction of the thrower, or paused, halted or redirected their movements."

But were the throwers intentionally trying to hit their octopus targets?

"The throws during interactions differed from throwing when other octopuses were not present," Scheel said. "Throws that hit an apparent target were a bit different, in ways suggestive of aiming, from throws that did not hit," hinting that debris flinging was targeted.

Humans typically teach toddlers that throwing things is not the best way to communicate. But for other animals that live in close-knit communities — such as chimpanzees, capuchin monkeys and dolphins — chucking objects at members of the same population can serve as an important social cue, according to the study.

Octopuses are known to be extremely dextrous and capable of manipulating diverse objects. For example, the veined octopus (Amphioctopus marginatus) stacks and carries coconut shells, which it uses to build a "mobile home." But octopuses, as a rule, are not social creatures; they typically live alone, and when they encounter other octopuses, they sometimes fight them or even eat them.

However, in recent decades, a growing body of evidence suggests that octopus interactions in some species are more complex than once thought — and throwing things may be one way the animals communicate, the scientists reported. 

In the regions of Jervis Bay where gloomy octopuses live, food and materials for shelter are plentiful; outside these patches of suitable habitat, resources are scarce. This could explain the unusual density of octopus populations there, which would, in turn, increase the number of encounters between creatures that would probably prefer to be the only octopus in town. Therefore, throwing debris may be a way for these normally solitary creatures to manage interactions with their octopus neighbors — including unwanted sexual advances, the researchers wrote.

Snow crabs in the Bering Sea once numbered in the billions. But after a recent and massive population crash the crabs have all but vanished from these waters — and they may not be coming back anytime soon.

In 2018, about 3 billion mature snow crabs (Chionoecetes opilio) inhabited the Bering Sea along with roughly five billion immature crabs, the Seattle Times reported. But by late 2021, those numbers hovered around 2.5 million and 6.5 million, respectively — a loss of nearly eight billion crabs in just three years. In February, the National Marine Fishing Service issued an official overfishing notice for the population, and in early October, officials at the Alaska Department of Fish and Game (ADFG) made the difficult decision to cancel the season's snow crab harvest for fear of wiping out the crustaceans altogether.

“Management of Bering Sea snow crab must now focus on conservation and rebuilding given the condition of the stock,” ADFG representatives said in a statement. The agency also canceled the fall harvest of Bristol Bay red king crabs (Paralithodes camtschaticus), due to low survey numbers. 

Miranda Westphal, an area management biologist with the Alaska Department of Fish and Game, called the decision "tremendously difficult." 

"It came after a lot of sleepless nights and a lot of tears. It was one of the hardest decisions we've ever had to make," she told Live Science

What caused the snow crab crash? The main culprit was almost certainly human-caused climate change, though unsustainable fishing practices may also have played a role, the Seattle Times reported.

Snow crabs thrive in the cold northern waters of the Bering Sea floor. For these crabs, water temperature isn’t just a matter of comfort; it plays a critical role in their lifecycle. As seawater cools, it becomes less salty and less buoyant, causing it to sink to the bottom of the ocean. Marine biologists refer to this chilly layer of water as the "cold pool, according to the National Oceanic and Atmospheric Administration (NOAA). Many fish and other types of marine life avoid the cold pool, but for juvenile snow crabs, it’s a sanctuary. With virtually no predators willing to venture into this layer's frigid waters, young crabs can grow up in peace.

But lately that protection has waned. Record heat waves in 2016, 2018 and 2019 stunted cold pool formation in the Bering Sea, leaving baby crabs vulnerable to predators, according to a Sept. 2 report published by NOAA. What's more, Westphal said, the warmer waters likely sped up the adult crabs' metabolism, causing them to starve. As anthropogenic climate change progresses over the next few decades, these types of heatwaves are projected to become more common, according to the report. 

In addition to climate change, some commercial fishing practices may have contributed to the sharp decline in crab numbers. Trawling vessels targeting other marine species in the Bering Sea frequently encounter, catch and discard unwanted snow crabs as "bycatch" ” And when snow crab fishers haul a catch aboard, they toss out crabs that are deemed too small, too young, or whose shells are discolored or marred in some way. 

Sometimes the crabs survive the shock of being suddenly transported to the surface and then thrown back into the water — but often they do not. In 2020, the ADFG estimated that over 30% of all snow crabs that were captured and tossed back into the Bering Sea died as a result, the Seattle Times reported in April. NOAA’s 2021 assessment for Bering Sea snow crabs corroborated these grim findings, with snow crab mortality rising that year and populations plummeting.

Crabbing is big business in Alaska. The cancellation of crab season this year and the uncertain future of the Bering Sea's snow crabs could have dramatic implications for the industry, which garnered some $280 million in 2016, Anchorage Daily News reported, and for many local fishers who depend on snow crabs for their livelihoods.

"People are simply going to go bankrupt and they’re not going to be able to feed their families," Jamie Goen, executive director for Alaska Bering Sea Crabbers, told KIMA-TV, a television station in Yakima, Washington. 

Goen's group, along with several others, is currently calling on the North Pacific Fishery Management Council to impose better conservation measures to help rebuild a sustainable snow crab population, KIMA-TV reported.

But for now, the crabs will remain off-limits for commercial fishers. "We want to give them the best chance to recover," said Westphal.

Thousands of globular cannonball jellyfish (Stomolophus meleagris) have washed ashore along a stretch of North Carolina coastline in what is being dubbed a "jellyfish jamboree."

Park rangers from the Cape Hatteras National Seashore, part of the National Park Service (NPS), snapped photos of the spectacle on Friday (Oct. 14) and shared it in a Facebook post.

The "large swarm" washed up along the northern edge of Ocracoke Island, one in a chain of islands that makes up the Outer Banks. The sudden influx of these squishy, stinger-less blobs coincides with the presence of red drum (Sciaenops ocellatus), a species of saltwater fish that's currently in the midst of spawning season — the fish’s larvae also happen to be the preferred snack for the jellyfish, according to the post.

Similar to actual cannonballs in both shape and size — the jellies weigh about 1 pound (450 grams) on average and measure 10 inches (24 centimeters) in diameter — the species is one of the most common types of jellyfish along the southeastern coast, according to the Georgia Department of Natural Resources.

So why did they wash up now?

"Jellyfish rely on winds and currents to help them swim. Colder water temperatures, winds and currents can all play a role in them washing ashore," the post read.

Related: Thousands of jellyfish swarm near Israel, mesmerizing images reveal

And the stars lined up particularly well this year: a red drum spawning event combined with colder water temperatures to create a huge seafood buffet for the voracious blobs, according to Newsweek.

"Why blooms occur in some years and not in others, or why sometimes blooms are larger in some years compared to others is all tied to environmental factors, but not well understood," Cheryl Lewis Ames, an associate professor of applied marine biology at the Graduate School of Agricultural Science, Tohoku University in Japan, told Newsweek. "In my several decades of jellyfish research I have found that few jellyfish species will reliably show up just when you expect them."

Jellyfish are swarming in massive numbers in the Mediterranean Sea, close to the port city of Haifa in northern Israel. The sea was "bedazzled with thousands of white dots," according to The Jerusalem Post, which also reported that the swarm extended below the surface to depths of several hundred meters.  

Officials with Israel’s Nature and Parks Authority (NPA) captured footage of the swarming nomad jellyfish (Rhopilema nomadica) in Haifa Bay on July 20 using aerial drones, and they shared the footage on the agency's website. The NPA also advised people against swimming in the area, due to the risk of painful jellyfish stings.

This unusually high concentration of jellyfish individuals, also known as a bloom, likely stems from human activities that may include pollution and climate change , NPA representatives said in a statement (translated from Hebrew).  

The explosion in jellyfish numbers this summer could have catastrophic consequences for the marine ecosystem near coastal Haifa, and could even affect industry and tourism, Ruthy Yahel, an NPA marine ecologist, said in the statement.

"We see great damage from it in many areas, such as ecological competition with the fish for food, economic damage, clogging of desalination plant pumps, cooling of power plants, damage to fishermen, and the public keeping their feet off the beaches because of the burning [from jellyfish stings]," Yahel said. (Remember: Despite the urban legend, don't treat jellyfish stings with pee, which can cause the jellyfish's stinging cells to release more venom. Instead, remove the tentacles with a tool — not your bare fingers — and splash something acidic, such as vinegar, on the wound, Live Science previously reported.)

Related: Scientists inserted disco 'strobe lights' into jellyfish to see how they function without brains

Jellyfish are a common sight off the coast of Israel during the summer, and large blooms were reported in 2015 and 2017, The Jerusalem Post reported. The University of Haifa maintains a website that tracks jellyfish swarms using reports from open water swimmers, divers, boaters, fishers, surfers, paddlers and kayakers. Its interactive map helps both fishing boats and beachgoers avoid areas of the ocean and beaches where jellyfish swarms have been spotted. 

Nomad jellyfish, currently the most common jellyfish species in waters near Haifa, are an invasive species that originated in tropical waters of the Indian and Pacific Oceans. Scientists suspect that the jellyfish invaded the Mediterranean from the Indian Ocean by using the Suez Canal — the artificial waterway in Egypt that connects the Mediterranean to the Red Sea through the Isthmus of Suez — CNN reported in 2015.

One possible cause for jellyfish blooms such as the recently-observed event, could be pollution; jellyfish may have flocked to this region in record numbers to escape sewage and dispersing solid waste that's pumped into the ocean, according to the NPA statement. Overfishing and population reduction in ocean animals that compete with jellyfish, such as sunfish, or that prey on them, such as sea turtles, could also explain why jellyfish are especially numerous this year, NPA representatives said.

Changing climate could also be playing a part in driving Haifa's jellyfish bonanza, Dror Angel, a marine ecologist in the University of Haifa’s Department of Maritime Civilizations, told The Jerusalem Post. "The past winter has been very rainy and cold at times. This may have affected the intensity of the blooms and their life cycle," Angel said. "We know for sure if there’s heavy rain, then lots of nutrients get washed into the sea. So there's more algae, plankton and more food for the jellyfish to eat."

Originally published on Live Science.

Octopuses are brainy creatures with sophisticated smarts, and now scientists have uncovered a clue that may partly explain the cephalopods' remarkable intelligence: Its genes have a genetic quirk that is also seen in humans, a new study finds.

The clues that scientists uncovered are called "jumping genes," or transposons, and they make up 45% of the human genome. Jumping genes are short sequences of DNA with the ability to copy and paste or cut and paste themselves to another location in the genome, and they've been linked to the evolution of genomes in multiple species. Genetic sequencing recently revealed that two species of octopus — Octopus vulgaris and Octopus bimaculoides — also have genomes that are filled with transposons, according to a study published May 18 in the journal BMC Biology.

In both humans and octopuses, most transposons are dormant, either shut down due to mutations or blocked from replicating by cellular defenses, the study authors reported. But one kind of transposon in humans, known as the Long Interspersed Nuclear Elements or LINE, may still be active. Evidence from prior studies suggests that LINE jumping genes are tightly regulated by the brain, but are still important for learning and for memory formation in the hippocampus.

When the scientists took  a closer look at octopus jumping genes that could freely copy and paste around the genome, they discovered transposons from the LINE family. This element was active in the octopus's vertical lobe — a brain section in octopuses that is  critical for learning and is functionally analogous to the human hippocampus, Graziano Fiorito, study coauthor and a biologist at the Anton Dohrn Zoological Station (SZAD) in Naples, Italy, told Live Science. 

Related: Octopuses torture and eat themselves after mating. Science finally knows why.

In the new study, the researchers measured one octopus transposon's transcription to RNA and translation to protein, and they detected significant activity in areas of the brain related to behavioral plasticity — how organisms change their behavior in response to different stimuli. "We were very happy because this is a sort of proof," said study coauthor Giovanna Ponte, a researcher in the SZAD Department of Biology and Evolution of Marine Organisms. 

Even though octopuses aren't closely related to animals with backbones, they nonetheless demonstrate behavioral and neural plasticity that's similar to that of vertebrates, Fiorito added. "These animals, like mammals, have the ability to adapt continuously and solve problems,"  and this evidence hints that the similarity may originate at the genetic level, he said. 

These findings not only connect jumping genes to octopus' intelligence, they also suggest that LINE transposons do more than just jump around. Rather, they have some role in cognitive processing, the authors suggested in a statement. Because jumping genes are shared by humans and octopuses, they may be good candidates for future research on intelligence and how it develops and varies between individuals within a species, according to the study. 

However, since octopuses are quite distant from humans on the tree of life, it's possible that active LINE transposons in the two groups are an example of convergent evolution.  This means their contribution to intelligence evolved separately in the two lineages, rather than originating in a shared ancestor, the scientists reported. 

Originally published on Live Science.

A crab species that was recently discovered in Australia fashions itself massive hats and coats made from living sponges, which makes the crustacean look like a wonderfully squeezable stuffed toy. 

(Don't be fooled, though — there's a tough exoskeleton beneath all the shaggy fluff!)

A family first spotted the crab, the newly named Lamarckdromia beagle, when it washed up on a beach near the city of Denmark in Western Australia. They sent the specimen to Andrew Hosie, curator of the crustacea and worms collections at the Western Australian Museum in Perth, who recognized the animal as some kind of sponge crab, albeit a "pretty unusual" one. 

"The extreme fluffiness was the give away for us," Hosie told Live Science in an email. "The sponge crabs are often hairy, but it is more like felt or velvet, rather than this complete shaggy coat."

Members of the sponge crab family (Dromiidae) use their sharp front claws to collect bits of sponges and ascidians — filter-feeders such as sea squirts — and use specialized back legs to hold these trimmings above their heads. In time, these trimmings accumulate to form a kind of tight-fitted cap over the crab, helping the animal avoid being spotted by predatory fish, other crabs and octopuses that might eat it. Sponges are also known to produce noxious chemicals, which likely make the crab a less tempting snack for predators, Hosie said.

Related: Watch a giant spider crab bust out of its own shell in wild time-lapse video 

Upon receiving the sponge-covered specimen, Hosie contacted Colin McLay, a retired marine biologist and former associate professor at the University of Canterbury in New Zealand, who has studied sponge crabs for decades. McLay confirmed that the crab was a previously-unknown species. 

The team then compared the crustacean with other members of the Lamarckdromia genus housed in the Western Australian Museum's collections. In doing so, they uncovered four additional L. beagle specimens that had been collected in various coastal locations between 1925 and 1983, but hadn't yet been described or flagged as the same species. Together, these specimens suggest that L. beagle can be found in shallow, subtidal waters between Hopetoun and Cape Naturaliste on Western Australia's south coast, Hosie said.

The fluffy crab species' name commemorates the HMS Beagle, the vessel that in 1836 carried British naturalist Charles Darwin to Albany, Australia, during its second survey expedition. "This voyage is considered to have made a profound impact on Darwin, leading him on his way to formulating his theory of natural selection," Hosie said. 

The name "beagle" also suits the newfound crab species because the animal's fluffy coat has the same reddish-brown color as the markings on the face and shoulders of a beagle, he added.

The researchers described the new crab species April 28 in the journal Zootaxa. 

Originally published on Live Science.