An isolated population of sperm whales in the Mediterranean Sea are splitting into two distinct groups with different dialects, a new study reveals. This shift has likely been happening for thousands of years, as two groups split from an initial single population.

The findings, published Tuesday (June 23) in the journal Proceedings of the Royal Society B: Biological Sciences, are providing a rare insight into the process of different dialects emerging among non-human species.

The sperm whales (Physeter macrocephalus) live in small social units of females and young, and they associate with other groups in the same area. They use social vocalizations called codas ‪—‬ shortpatterns of clicks ‪—‬ to communicate. The particular codas they use identify them as being part of the same cultural group.

Taylor Hersh, a researcher in the School of Biological Sciences at the University of Bristol in the U.K. and first author of the research, and her colleagues have analyzed codas recorded over almost 20 years in the Mediterranean, where there is a unique population of a few thousand sperm whales, to see if they all use the same dialect.

Sperm whales entered the Mediterranean via the Strait of Gibraltar about 20,000 years ago, and they have spread throughout the area. The whales rarely leave the sea ‪—‬ even males, which normally migrate. Other sperm whales don't seem to enter often, either, so the Mediterranean ones are effectively isolated from other populations and are considered an endangered subpopulation.

"The sperm whales in the Mediterranean are really cool," Hersh told Live Science. "I've always thought of them as the weirdos of the sperm whale world in that they don't leave through the Strait of Gibraltar even though they could. They are unique, and for a long time, they were also thought to be acoustically unique."

The thinking was that all the sperm whales in the Mediterranean belonged to the same clan, identified by their use of a single coda 90% of the time. This coda consists of three clicks and then a pause before the fourth and final click ‪—‬ a pattern called the three-plus-one type.

But the analysis by Hersh's team of 5,291 codas recorded between 2003 and 2021 revealed that sperm whales living in the eastern Mediterranean around the Hellenic Trench, off Greece, have a slightly different dialect from that used by animals in the western basin around Spain's Balearic Islands.

The eastern whales produce a distinct form of the three-plus-one coda. "It's a very similar pattern of clicks, but it's much, much faster," Hersh said.

In some recordings, whales in the eastern Mediterranean produced the slower coda, showing they were familiar with both dialects.

"The western sperm whales religiously stick to their dialect, but there were four instances of eastern whales using the western dialect," Hersh said. "The question of why is still an open one. Their dialect seems to be a lot more diverse than we expected. They do occasionally make those slow three-plus-one codas, but they make a lot of other coda types, too."

Hersh hopes further recordings alongside records that tie individual whales to sounds and events might help elucidate why the whales switch between dialects.

"It's exciting to see this study showing different populations behaving closely, but also differently," said Gašper Beguš, linguistics lead at Project CETI, a nonprofit organization that aims to translate the communication of sperm whales.

The study paints a picture of sperm whales progressively occupying the Mediterranean from west to east, with the dialect of one group gradually changing. "The groups in the east clearly remember the western dialect because they have these 'throwback' days," Hersh said.

It's still a mystery how and why these dialects evolved.

"Every speech is a dialect; the question is how did they arise and why?" said Beguš, who wasn't involved in the new study. He said the historical change in habitat does help to show which dialect came first. "In the Mediterranean, maybe they're forming different groups, so that's why they're trying to distinguish themselves," he told Live Science, giving the parallel of young people who distinguish themselves from previous generations by coming up with new slang.

"It's possible that these two groups with repertoires that are very similar but still distinctive could represent a sort of midway phase,” Ellen Jacobs, a marine biologist at Aarhus University in Denmark who wasn't involved in the research, told Live Science via email.

"Changes in the rhythm might be a very feasible and meaningful way for coda signals to start to diverge," she said, like the way the English words "How do you do?" got mashed together until they morphed into "howdy."

The timescale on which a sperm whale dialect develops is uncertain, but it's likely a slow process, according to Hersh. "It's probably happening on the scale of hundreds and thousands of years, because sperm whales can live into their 60s and 70s. And this study is looking over 19 years of data, and that's just a snapshot of one animal's life," Hersh said.

This means the eastern whale dialect was conceivably emerging in the Mediterranean Sea as famous human civilizations were speaking different languages on the surrounding lands, including when the ancient Greeks and Romans were rising and then falling.

"Maybe if we could leave them for another 10,000 years, we would come back to find the completely separated dialects of clans," Jacobs said.

Scientists have discovered a vast whale graveyard stretching for hundreds of miles in the Indian Ocean, with some fossil bones dating back over 5 million years.

The deep-sea "megasite," which the researchers have named the Diamantina Zone necropolis, is the most extensive accumulation of whale carcasses and fossils ever found, the researchers reported in a new study published Wednesday (June 10) in the journal Nature.

"It covers over 1,200 kilometers [750 miles], which just defies belief," Nick Pyenson, a curator of fossil marine mammals at the Smithsonian National Museum of Natural History in Washington, D.C., who wasn't involved in the study, told Live Science. "'Megasite' is a totally appropriate term. I think they've uncovered something really special."

"The density is crazy"

Xiaotong Peng, a deep-sea researcher at the Chinese Academy of Sciences' Institute of Deep-sea Science and Engineering, and his colleagues used an underwater vehicle called the Fendouzhe submersible to survey the seafloor in the Diamantina Zone, an area of ridges and fractures in the southeastern Indian Ocean.

After initially spotting one fossil, the team conducted 32 dives covering a survey area of about 0.25 square miles (0.64 square kilometers). In total, they identified 476 whale fossils and five carcasses of whales that had died more recently, known as whale falls, at depths of between 13,800 and 23,000 feet (4,200 to 7,000 meters).

Extrapolating from these figures, the authors said there could be seven to eight whale carcasses and about 750 fossils per square kilometer in the area.

The largest carcass is a 16.4-foot-long (5 m) skeleton from an Antarctic minke whale (Balaenoptera bonaerensis), the researchers said, but most of the remains are from beaked whales ‪—‬ marine mammals we know little about because they live in the open ocean and spend a lot of time diving.

The five active whale falls are covered in bacteria that live without light or oxygen and break down the oils in the whales' bones, producing hydrogen sulfide. This source of chemical energy enables the carcasses to host diverse communities of jellyfish, brittle stars, bone-eating Osedax worms and bivalve mollusks, which together reach densities of up to 2,840 individuals per square meter, the authors discovered.

Many of the members of the whale-fall communities may also be newly discovered species, the authors wrote, because although most could be matched to the genus or family level using DNA data from samples, only one could be confidently assigned to a species: a clam known as Abyssogena southwardae.

"The density is crazy, as is the fact that they're probably all new to science," said Stephen Godfrey, curator of paleontology at the Calvert Marine Museum in Maryland who wasn't involved in the study. "It's like each one of these whale falls is a new little restaurant that opens up in a 1,200-kilometer-long [745 miles] strip mall," he told Live Science.

These are the deepest whale-fall communities ever found, with the one at about 22,000 feet (6,700 m) being about 8,200 feet (2,500 m) deeper than any other known one, according to the study authors.

A fossil deposit being formed

Peng and his colleagues recovered 43 fossils and dated 33 of them based on the ratios of strontium isotopes present. The fossils belonged to five beaked whale species and one species of baleen whale, a group that includes bowhead and humpback whales.

The oldest fossil found in the area belonged to an extinct beaked whale in the Pterocetus genus that dates back about 5.3 million years, to the Early Pliocene. Another fossil find represented a new species, which the authors have named Pterocetus diamantina.

All that remains of most of the specimens is the bony upper jaw, or rostrum. These fossils came mainly from two species: the Andrews' beaked whale (Mesoplodon bowdoini) and the strap-toothed whale (Mesoplodon layardii). Both of these species still inhabit the Indian Ocean, but the fossils the team discovered could be up to 1 million years old.

"The really awesome thing is that this megasite is showing beaked whale ecology over geologic time scales, so you are getting extinct species overlapping the fossil remains of extant species," Pyenson said.

The megasite is analogous to either the famous Lagerstätte fossil deposits, where there is high-quality preservation, including of soft tissue, or to the Burgess Shale in Canada, which has a huge abundance of animals, Godfrey said, "only here, you have one that's still forming."

Beaked whales are rarely seen, so it might seem strange to find the remains of so many individuals in one place. But Godfrey said these animals might preserve better because of the staying power of their rostra, which have one of the highest known bone densities and mineral contents among living vertebrates.

This means they can persist long enough at great depths without being dissolved or consumed by bone-eating worms that they then become encrusted with ferromanganese oxides, solidifying and encasing the bone in a kind of natural sarcophagus.

"This seals the specimen in, so it will last in perpetuity, or at least over 5 million years, and who knows how much longer," Godfrey said.

Why so many dead whales?

The authors saw many squid and fish in the dives in the Diamantina Zone, which suggests the area provides an ideal deep-water foraging ground for beaked whales. This might mean more whales live and die in the area, even though when a whale dies, its decomposition can make it expand with gas and float on the surface for great distances before eventually falling to the seabed.

Peng and his colleagues also suggested that there might be an increased risk of death by beaked whales being tempted to chase prey below their maximum observed diving depth of about 10,000 feet (3,000 m), which puts them at risk of lung collapse or decompression sickness.

Another possibility is that the V-shaped topography of the Diamantina Zone may funnel sinking carcasses into a smaller area, the authors suggested.

"I think what they're dealing with is an analogue to the terrestrial tar pits or caves that are natural traps where biological remains accumulate over time," Pyenson said.

That's only part of the story, though. Normally, ancient remains on the seabed would get covered by sediment from eroded rocks, so we'd never see the fossils. But the sedimentation rate close to the Diamantina Zone is incredibly low ‪—‬ just 0.02 to 0.22 inches (0.05 to 0.55 centimeters) per 1,000 years, the study authors noted. This means skeletal remains could be exposed for hundreds of thousands of years at the flat bottom parts of the zone and for millions of years on slopes or uplifted sections, the team said.

They think there might be other similar "necropolises" off South Africa, the Iberian Peninsula, and the remote Crozet and Kerguelen islands near Antarctica, where some fossils have already been discovered by trawling.

How much do you know about killer whales? Find out with our orca quiz!

This dazzling satellite photo shows a glowing ring of plankton surrounding a remote group of New Zealand islands. The illuminated landmasses are hotspots for deadly whale stranding events, which are tied to the same underwater structure that birthed this spectacular bloom.

The gleaming ring encircles the Chatham Islands — a group of 10 islands in the Pacific Ocean around 520 miles (840 kilometers) west of Christchurch, on the east coast of New Zealand's South Island. The largest of those islands, Chatham Island and Pitt Island, are approximately 36 miles (58 km) and 9 miles (15 km) across, respectively. (The other landmasses are much smaller and are not clearly visible in the image.)

The Chatham Islands are surrounded by the Chatham Rise — a shallow underwater plateau that extends up to 900 miles (1,450 km) from the South Island's east coast. This hidden structure acts like a giant ramp that funnels cold, nutrient-rich waters to the ocean's surface. In the summer, warmer seasonal currents mix with this nutrient-rich water, providing the perfect conditions for algae to bloom.

The circular bloom in the photo was one of the largest in recent decades. It consists mostly of coccolithophores, a group of photosynthetic plankton, or "phytoplankton," that convert sunlight into energy and surround themselves with intricate calcium carbonate armor.

The satellite image was captured with a special near-infrared filter, which likely enhanced the algae's vivid hues. However, the blooming microorganisms would have been clearly visible to the naked eye from space, according to NASA's Earth Observatory.

Phytoplankton are the base of the pelagic (open-water) food web, similar to plants' role in terrestrial environments. As a result, the Chatham Islands are marine biodiversity hotspots that are home to various animals, including penguins, albatrosses, seals and sea lions, as well as commercially important populations of cod and lobsters.

At least 25 species of whales and dolphins, or cetaceans, are also drawn to the islands to feed, including orcas (Orcinus orca), sperm whales (Physeter macrocephalus) and pilot whales (Globicephala), according to New Zealand's Department of Conservation (DOC). However, this is not always a good thing for the visitors.

Large groups of cetaceans often get disoriented in the shallow waters and can end up accidentally swimming too close to shore and getting trapped as the tide goes out, which is often fatal without human intervention.

Chatham Island has experienced multiple strandings over the past few years, including an event in October 2022 when nearly 500 pilot whales were euthanized on Chatham Island after washing up over the space of around four days, according to a DOC report. In 1918, more than 1,000 pilot whales are also believed to have died there after washing ashore, which remains the most deadly whale stranding event in recorded history. (Pilot whales are particularly prone to stranding because they are highly social, so an entire pod can be dragged into danger by a single injured or disoriented individual.)

Cetaceans are not the only creatures that have met an untimely end on the Chatham Islands. The archipelago was previously home to at least eight endemic bird species that have since gone extinct, including the Chatham penguin (Eudyptes warhami). Most of these species disappeared between 150 and 200 years ago due to the island's first human settlers, who arrived there from Polynesia in the 15th century.

See more Earth from space

Scientists have captured first-of-its-kind footage of a sperm whale violently headbutting another sperm whale out of the blue.

Researchers filmed the clip with a drone during fieldwork off the Azores and Balearic Islands. It is one of three cases of headbutting between 2020 and 2022 that the scientists reported in a new study published Monday (March 23) in the journal Marine Mammal Science.

"It was really exciting to observe this behaviour, which we knew had been hypothesised for such a long time, but not yet documented and described systematically," study lead author Alec Burslem, a quantitative physiological ecologist at the University of Hawaii, said in a statement.

Mariners and whalers in the 18th and 19th centuries told stories of sperm whales (Physeter macrocephalus) using their heads to push each other and strike boats. The most famous anecdote dates to 1820, when an 89-foot-long (27 meters) whaleship called the Essex reportedly sank after a large male sperm whale headbutted it twice off the Galapagos Islands, according to the statement.

Reports of the Essex's sinking inspired Herman Melville's 1851 novel "Moby Dick," which tells the fictional story of a whaleship captain's obsessive and vengeful quest to find a giant white sperm whale that bit off his leg.

However, until now, scientists had never documented sperm whales' headbutting behavior.

It's still unclear exactly why sperm whales headbutt each other, but some researchers think the behavior originated from competition and physical contests between males, according to the statement. Other experts argue that headbutting is unlikely to have evolved as a widespread behavior in sperm whales, however, because using the head as a weapon can damage brain structures in these whales that are vital for echolocation and social communication.

The footage showed young males participating in headbutting, rather than mature males as was previously hypothesized, raising questions about the role of the behavior in whale groups.

It's possible that headbutting is common in sperm whales, and that researchers are only seeing it now thanks to better and more accessible technology.

"This unique overhead perspective for observing and documenting near-surface behaviour is just one of the ways drone technology is transforming the study of wildlife biology," said Burslem, who was at the University of St Andrews in Scotland when he did this research.

"It's exciting to think about what as-yet unseen behaviours we may soon uncover, as well [as] how more headbutting observations may help us to shed light on the functions the behaviour may serve," he said. "If there are people out there with similar footage, we would be very keen to hear from them."

Animal quiz: Test yourself on these fun animal trivia questions

Harpoons crafted from the bones of humpback and southern right whales show Indigenous groups in what is now Brazil were hunting whales 5,000 years ago.

The discovery, which included 118 whale bones and crafted artifacts, reveal that prehistoric whaling was not confined to people in temperate and polar climates in the Northern Hemisphere, according to a study published Jan. 9 in the journal Nature Communications.

"Whaling has always been enigmatic," because it's difficult to distinguish bone tools made from actively hunted and stranded animals in the archaeological record, study co-author André Carlo Colonese, a research director at the Autonomous University of Barcelona, told Live Science.

So the new tools are significant because their discovery alongside multiple bone remains from members of the same species represents some of the oldest evidence of active whale hunting in the world, the authors wrote in the study.

Prehistoric whaling

For prehistoric people, whales provided huge feasts, oil for warmth, and bones for tools and cultural ornaments and accessories. Although coastal communities have opportunistically salvaged these resources from beached whales for at least 20,000 years, the evidence of active hunting is much younger. For example, people hunted large whales with deer bone harpoons 6,000 years ago in what is now South Korea, and harpoons from around 3,500 to 2,500 years ago have been uncovered in the Arctic and sub-Arctic.

Colonese and his team did not originally set out to investigate early whaling. Instead, they were trying to document the marine species that were used by Indigenous Sambaqui populations in southern Brazil. To do so, they analyzed the molecular signature of precolonial cetacean (whale, dolphin and porpoise) bones at the Joinville Sambaqui Archaeological Museum in Brazil. Of the 118 bone remains with an identifiable cetacean species, most were from southern right whales, but many bones were from humpback whales. Only 37 had been crafted into items such as pendants.

It was "completely random" that one of the museum's curators brought out a box of what were believed to be sticks, Colonese said. But based on their design, such as hollow centers for a wooden shaft and carved tips, he immediately recognized them as harpoons. The team identified 15 harpoon elements, including heads and shaft components, made from either southern right whale or humpback whale rib bones.

The researchers took tiny samples from two harpoon foreshafts to determine their age, which revealed that the tools were between 4,710 and 4,970 years old. Colonese said he jumped for joy when he saw the results because these are some of the oldest harpoons found anywhere in the world — over 1,000 years older than the Arctic and sub-Arctic examples.

The discovery also showed that these Indigenous populations in Brazil were not simply gathering mollusks and catching fish. "The conventional idea was that the Sambaquis didn't have the technology" for whaling, Colonese said. "This is telling us that they were actually hunting."

"It's a very spectacular, informative discovery," Jean-Marc Pétillon, an archaeologist at the University of Toulouse in France who was not involved in the research, told Live Science.

Although it's not clear that these particular harpoons were used to hunt whales — as opposed to other marine animals, such as seals — this new evidence helps to contradict the assumption that whaling was practiced only in the Northern Hemisphere, according to Pétillon.

"Having these people living in southern Brazil in tropical conditions that also did whaling is also a way to change our perspective on these maritime exploitation systems," he said.

In March 2019, researchers off the coast of southwestern Australia witnessed a gruesome scene: a dozen orcas ganging up on one of the biggest creatures on Earth to kill it. The orcas devoured huge chunks of flesh from the flanks of an adult blue whale, which died an hour later. This was the first-ever documented case of orca-on-blue-whale predation, but it wouldn't be the last.

In recent months, orcas (Orcinus orca) have also been spotted abducting baby pilot whales and tearing open sharks to feast on their livers. And off the coast of Spain and Portugal, a small population of orcas has begun ramming and sinking boats.

All of these incidents show just how clever these apex predators are.

"These are animals with an incredibly complex and highly evolved brain," Deborah Giles, an orca researcher at the University of Washington and the nonprofit Wild Orca, told Live Science. "They've got parts of their brain that are associated with memory and emotion that are significantly more developed than even in the human brain."

But the scale and novelty of recent attacks have raised a question: Are orcas getting smarter? And if so, what's driving this shift?

It's not likely that orcas' brains are changing on an anatomical level, said Josh McInnes, a marine ecologist who studies orcas at the University of British Columbia. "Behavioral change can influence anatomical change in an animal or a population" — but only over thousands of years of evolution, McInnes told Live Science.

Related: Scientists investigate mysterious case of orca that swallowed 7 sea otters whole

But orcas are fast learners, which means they can and do teach each other some terrifying tricks, and thus become "smarter" as a group. Still, some of these seemingly new tricks may in fact be age-old behaviors that humans are only documenting now. And just like in humans, some of these learned behaviors become trends, ebbing and flowing in social waves.

Frequent interactions with humans through boat traffic and fishing activities may also drive orcas to learn new behaviors. And the more their environment shifts, the faster orcas must respond and rely on social learning to persist.

Teaching hunting strategies 

There's no question that orcas learn from each other. Many of the skills these animals teach and share relate to their role as highly evolved apex predators.

Scientists described orcas killing and eating blue whales (Balaenoptera musculus) for the first time in a study published last year. In the months and years that followed the first attack in March 2019, orcas preyed on a blue whale calf and juvenile in two additional incidents, pushing the young blue whales below the surface to suffocate them.

This newly documented hunting behavior is an example of social learning, with strategies being shared and passed on from adult orcas to their young, Robert Pitman, a marine ecologist at Oregon State University's Marine Mammal Institute, told Live Science in an email. "Anything the adults learn will be passed along" from the dominant female in a pod to her offspring, he said.

Taking down a blue whale "requires cooperation and coordination," Pitman said. Orcas may have learned and refined the skills needed to tackle such enormous prey in response to the recovery of whale populations from whaling. This know-how was then passed on, until the orcas became highly skilled at hunting even the largest animal on Earth, Pitman said.

Old tricks, new observations 

Some of the gory behaviors researchers have observed recently may actually be long-standing habits.

For instance, during the blue whale attacks, observers noted that the orcas inserted their heads inside live whales' mouths to feed on their tongues. But this is probably not a new behavior — just a case of humans finally seeing it up close.

"Killer whales are like humans in that they have their 'preferred cuts of meat,'" Pitman said. "When preying on large whales, they almost always take the tongue first, and sometimes that is all they will feed on."

Tongue is not the only delicacy orcas seek out. Off the coast of South Africa, two males — nicknamed Port and Starboard — have, for several years, been killing sharks to extract their livers.

Although the behavior surprised researchers at first, it's unlikely that orcas picked up liver-eating recently due to social learning, Michael Weiss, a behavioral ecologist and research director at the Center for Whale Research in Washington state, told Live Science.

Related: Orcas attacked a great white shark to gorge on its liver in Australia, shredded carcass suggests

That's because, this year, scientists also captured footage of orcas slurping down the liver of a whale shark off the coast of Baja California, Mexico. The likelihood that Port and Starboard transferred their know-how across thousands of miles of ocean is vanishingly small, meaning liver-eating is probably a widespread and established behavior.

"Because there are more cameras and more boats, we're starting to see these behaviors that we hadn't seen before," Weiss said.

Sharing scavenging techniques 

Orcas master and share more than hunting secrets. Several populations worldwide have learned to poach fish caught for human consumption from the longlines used in commercial fisheries and have passed on this information.

In the southern Indian Ocean, around the Crozet Islands, two orca populations have increasingly scavenged off longlines since fishing in the region expanded in the 1990s. By 2018, the entire population of orcas in these waters had taught one another to feast on longline buffets, with whole groups that previously foraged on seals and penguins developing a taste for human-caught toothfish.

Sometimes, orcas' ability to quickly learn new behaviors can have fatal consequences. In Alaska, orcas recently started dining on groundfish caught by bottom trawlers, but many end up entangled and dead in fishing gear.

"This behavior may be being shared between individuals, and that's maybe why we're seeing an increase in some of these mortality events," McInnes said.

Playing macabre games 

Orcas' impressive cognitive abilities also extend to playtime.

Giles and her colleagues study an endangered population of salmon-eating orcas off the North Pacific coast. Called the Southern Resident population, these killer whales don't eat mammals. But over the past 60 years, they have developed a unique game in which they seek out young porpoises, with the umbilical cords sometimes still attached, and play with them to death.

Related: 'An enormous mass of flesh armed with teeth': How orcas gained their 'killer' reputation

There are 78 recorded incidents of these orcas tossing porpoises to one another like a ball but not a single documented case of them eating the small mammals, Giles said. "In some cases, you'll see teeth marks where the [killer] whale was clearly gently holding the animal, but the animal was trying to swim away, so it's scraping the skin."

The researchers think these games could be a lesson for young orcas on how to hunt salmon, which are roughly the same size as baby porpoises. "Sometimes they'll let the porpoise swim off, pause, and then go after it," Giles said.

Are humans driving orcas to become "smarter"? 

Humans may indirectly be driving orcas to become smarter, by changing ocean conditions, McInnes said. Orca raids on longline and trawl fisheries show, for example, that they innovate and learn new tricks in response to human presence in the sea.

Human-caused climate change may also force orcas to rely more heavily on one another for learning.

In Antarctica, for instance, a population of orcas typically preys on Weddell seals (Leptonychotes weddellii) by washing them off ice floes. But as the ice melts, they are adapting their hunting techniques to catch leopard seals (Hydrurga leptonyx) and crabeater seals (Lobodon carcinophaga) — two species that don't rely on ice floes as much and are "a little bit more feisty," requiring orcas to develop new skills, McInnes said.

While human behaviors can catalyze new learning in orcas, in some cases we have also damaged the bonds that underpin social learning. Overfishing of salmon off the coast of Washington, for example, has dissolved the social glue that keeps orca populations together.

"Their social bonds get weaker because you can't be in a big partying killer-whale group if you're all hungry and trying to search for food," Weiss said. As orca groups splinter and shrink, so does the chance to learn from one another and adapt to their rapidly changing ecosystem, Weiss said.

And while orcas probably don't know that humans are to blame for changes in their ocean habitat, they are "acutely aware that humans are there," McInnes said.

Luckily for us, he added, orcas don't seem interested in training their deadly skills on us.

Rare tusked whales have been identified and photographed alive at sea for the first time following a herculean research effort off the shores of Mexico, a new study finds.

The newly-sighted cetaceans are ginkgo-toothed beaked whales (Mesoplodon ginkgodens), which were previously only known from dead individuals that had washed ashore and from bycatch. This isn't all that unusual for beaked whales, which are deep divers and notoriously cryptic, spending their lives away from coastlines.

"Beaked whales are the largest least-known animals left on the planet," study co-author Robert Pitman, an affiliate of the Marine Mammal Institute at Oregon State University, told Live Science in an email. "It is exciting to think that there [are] still organisms here on earth that weigh over a ton and have never been identified alive in the wild."

The hunt for and subsequent discovery of the elusive creatures was sparked by a recording of a distinct echolocation pulse in the North Pacific. Researchers began searching for the animals responsible for the mysterious sonar signal in 2020, and in June of 2024, it led them to a single beaked whale. Within days of that sighting, the team then found a small group of the whales, including a battle-scarred adult male and adult female with a calf.

Beaked whale species can be difficult to tell apart, so simply observing the whales wasn't enough to identify them. The team only confirmed what they had seen after collecting a DNA sample by shooting one of the whales with a crossbow. (Don't worry, the whale is fine.)

The researchers published their findings online July 28 in the journal Marine Mammal Science, which will appear in the upcoming January 2026 issue of the journal. Study lead author Elizabeth Henderson, a bioacoustic researcher at the Naval Information Warfare Center, Pacific, said that the findings demonstrated the benefits of determination and not giving up.

"Myself and some of the other folks on this trip (Gustavo Cardenas, Jay Barlow) spent five years looking for these whales; we spent every year since 2020 searching off Baja to find them, and that effort and determination paid off with a huge reward," Henderson told Live Science in an email.

Ginkgo-toothed beaked whales are so named because the males have a pair of teeth that resemble the fan-shaped leaves of a ginkgo tree. For the whales, almost all of this shape is hidden in the jaw and gum tissue, with only the tip of each tooth visible on either side of their mouth. The teeth grow into small tusks as the males mature, and aren’t for eating, but are used as weapons.

"They feed on small squids and fishes by suction feeding, so they don’t need teeth," Pitman said. "As a result, females are toothless their entire lives, but males retain a single pair of enlarged teeth in the lower jaw that they use as tusks to fight over access to reproductive females."

When the team finally tracked down the whales, they saw that one adult male was seemingly battle-hardened with a worn tusk, bruising and scars. The other whales the researchers recorded across six separate observations were marked, too, and not just from other whales. Their scars included distinctive white blobs indicative of bites from cookiecutter sharks — little sock puppet-like fish that feed by ripping cookie-shaped chunks out of larger animals.

The team documented the whales with binocular observations, photographs and hydrophones (underwater microphones). During the fifth encounter, one of the whales swam within 66 feet (20 meters) of the stern of the researchers' ship, which is when Pitman fired his 150-pound (68-kilogram) draw-weight crossbow loaded with a modified punch-tip arrow.

"The crossbow arrow ('bolt') extracts a tiny, pencil-eraser-sized plug of skin and blubber," Pitman said. "We have collected thousands over the years, from dozens of whale and dolphin species."

Henderson compared the crossbow shot to an ear-piercing gun, while Pitman noted that any one of the whales' cookicutter shark bites probably took 50 times more tissue than the crossbow. The arrow didn't stick in the whale, so the researchers could retrieve it and the tissue. With a sample in the bag, the researchers then sent the tissue to a geneticist for testing.

"It took a few days to process the material and run the tests, and we were all waiting with [bated] breath," Henderson said. "When we got the results back we were all a bit shocked — while they did look like that species, this was not the expected area of their distribution so we had discounted that as a possibility — but we were also thrilled to finally have the mystery solved."

Ginkgo-toothed beaked whale strandings are fairly common in the western Pacific, but only two individuals have ever been recorded stranding in the eastern Pacific. The researchers had initially suspected that the whales they were seeing were Perrin's beaked whales (Mesoplodon perrini), which Pitman said are known from only six stranded specimens off southern California and are the least known marine mammals (and large animals) in the world.

Pitman noted that the team now hopes to go looking for Perrin’s beaked whales and the two other species of beaked whales that have yet to be identified alive in the wild, putting faces to more underwater calls.

"This is important because once we match up the calls to all the individual species, then we can use passive acoustic monitoring (towing hydrophones behind vessels, drifter buoys, etc.) and finally learn where these whales live, how many there are, and how vulnerable they are to human disturbances, especially high-seas fisheries," Pitman said.

A rocket-like jellyfish, a majestic Komodo dragon and a dangerous surfing encounter are just a few of the stunning photographs captured by the finalists for the Ocean Photographer of the Year 2025 competition. The competition includes categories such as Impact and Hope, which have solicited breathtaking photographs that capture diverse forms of marine life and human interaction with the ocean.

The overall and category winners of the contest, hosted by Oceanographic Magazine and watch company Blancpain, will be announced in September. But all of the finalists' photos emphasize the need to protect the planet.

"In the midst of a deepening climate and biodiversity crisis on our blue planet, ocean photography has never been more important," Will Harrison, director of Ocean Photographer of the Year, said in a statement from the organization. "These images are far more than just beautiful; they are powerful visual testaments to what we stand to lose, and they remind us of the urgent need for protection."

Here are some of the gorgeous photos.

Synchronized swimmers

Photographer Yuka Takahashi, a finalist in the "Young" category of the competition, captured a pair of synchronized humpback whales in French Polynesia swimming through rays of sun. "These two humpback whales are always seen together, and I was fortunate to capture this rare moment of synchronicity," Takahashi said. "To me, this photo reflects the strong bond between them while also revealing their playful and curious personalities."

Warm bath

In this image, snapped by "Wildlife" category finalist and photographer Suliman Alatiqi, a Komodo dragon (Varanus komodoensis) looms over an Indonesian shore. Because Komodo dragons are cold-blooded, they rely on cold water or mud to regulate their body temperature in the summer. They also travel across seabeds to search for food and mates.

Related: Ocean Photographer of the Year 2024: See stunning photos of hungry whale, surfing seagull, freaky fish babies, land-loving eel and adorable toxic octopus

Collateral damage

Photographer Natnattcha Chaturapitamorn snapped this image of fishers unloading their catches at a Bangladeshi harbor during sunrise, which is a finalist in the "Impact" category.

"Amidst this industrious energy, the presence of an endangered species serves as a reminder of the urgent need to protect marine biodiversity," Chaturapitamorn said. "As global fish stocks decline, safeguarding threatened species like this is vital, not only for ecological balance but for the long-term sustainability of fishing communities that depend on the ocean’s bounty."

Stranded

On July 1, wildlife veterinarians received a call about a humpback whale stranded on an Australian beach, and photographer Craig Parry documented the harrowing scene from above. For 15 hours, rescue teams and other members of the community worked to save the whale but were unsuccessful.

"While the outcome was heartbreaking, witnessing the collaboration and compassion shown by multiple agencies and volunteers was incredibly moving — a powerful reminder of what can be achieved when people come together with a shared purpose," said Parry, whose photo is a finalist in the "Human Connection" category.

School of fish

This mesmerizing image, taken in Indonesia by photographer Kim Hyeon Min, captures a school of juvenile fish circling around a tower of coral and is a finalist in the "Hope" category. The vibrancy of the coral suggests it has been unaffected by bleaching and is still able to host a miniature ecosystem for surrounding creatures. "In a time when marine ecosystems are rapidly disappearing, this image is a reminder of what we still have — and a hopeful glimpse of what we must protect for the future," Hyeon Min said.

Otherworldly jellyfish

Jellyfish are often described as alien-like, and this ethereal image captured in Spain by photographer Toni Bertran Regàs takes that comparison to new heights with this finalist in the "Fine Art" category.

"I've always been fascinated by the resemblance between jellyfish and space rockets," Bertran Regàs said. "I was looking for a photograph that conveyed that connection: a rocket leaving Earth. To do this, I used a fisheye lens and took the photo just as the sun was rising. Snell's Window" — an underwater optical phenomenon — "helped me create the Earth, the particles were the stars, and the sun luckily appeared behind it."

Monster waves

Photographer Ben Thouard, a finalist in the "Adventure" category, captured a day of rough seas in Nazaré, Portugal. Though the water was too dangerous for many surfers, two gave it a go. Despite the difficulty of photographing between huge waves and through salt water in the air, Thouard eventually shot this moment.

Scientists have discovered a "deceptively cute" ancient whale with large eyes and razor-sharp teeth that devoured prey off Australia around 26 million years ago.

The newly discovered Janjucetus dullardi is one of the earliest known cousins of filter-feeding baleen whales, including the gigantic blue whale (Balaenoptera musculus). However, J. dullardi was much smaller than its living relatives, with a compact body built for speed.

Researchers identified this new species from pieces of skull found on the coast of southeastern Australia. The individual it belonged to was a juvenile or subadult, around 7 feet (2.1 meters) long, according to a study published Tuesday (Aug. 12) in the journal Zoological Journal of the Linnean Society.

"It's essentially a little whale with big eyes and a mouth full of sharp, slicing teeth," study lead author Ruairidh Duncan, a paleontology doctoral student at the Museums Victoria Research Institute and Monash University in Australia, said in a statement. "Imagine the shark-like version of a baleen whale — small and deceptively cute, but definitely not harmless."

Related: Ancient whale 'graveyard' discovered under melting Russian glacier

J. dullardi belonged to a family of small whales called mammalodontids, which lived in warm, shallow waters off Australia and New Zealand during the Oligocene Epoch (33.9 million to 23 million years ago). This is not long, in evolutionary time, from when the ancient ancestors of today’s whales first returned to the ocean some 50 million years ago.

A school principal named Ross Dullard first spotted the J. dullardi fossils while walking along the beach of Half Moon Bay, near Melbourne, in 2019. The fossils were exposed at the base of a wave-eroded rock outcrop — part of a geological formation known as the Jan Juc Marl, which is between about 24 million and 28 million years old. After discovering the fossils, Dullard donated them to Museums Victoria.

"This kind of public discovery and its reporting to the museum is vital," senior study author Erich Fitzgerald, a senior curator of vertebrate paleontology at the Museums Victoria Research Institute, said in the statement. "Ross' discovery has unlocked an entire chapter of whale evolution we've never seen before. It's a reminder that world-changing fossils can be found in your own backyard."

Researchers used photography, microCT scans and other techniques to perform a detailed analysis of the fossils, which included preserved teeth and inner ear structures. The team deduced that J. dullardi was a previously unknown species of mammalodontid and named it after Dullard. One of the reasons researchers could tell it was a young whale was because of a lack of wear on the teeth.

Southeastern Australia has become a hotspot for ancient whale fossils, with two other mammalodontid species recovered from the Jan Juc Marl formation. Researchers continue to find fossils in this region and expect more discoveries in the years ahead, according to the statement.

"This region was once a cradle for some of the most unusual whales in history, and we're only just beginning to uncover their stories," Fitzgerald said.

Blue whales sing less when they are starving and sing more when food is plentiful, a recent study revealed. Researchers listened to whales off California for six years and found that their singing increased following a marine heatwave — despite multiple news outlets claiming that blue whales are going silent.

Whales have a range of vocalizations, but only the males sing. There's evidence of males using their songs to attract females and communicate with other males, said study lead author John Ryan, a biological oceanographer at the Monterey Bay Aquarium Research Institute in California. "It's an essential part of how they sense their world and interact with each other," he told Live Science.

The singing also provides researchers with an opportunity to study whales. Sound travels very well underwater, so in the vast ocean, listening for animals can be more efficient than looking for them, even when the animals you're looking for are the largest on Earth.

"We can see one of these whales if we're up close and at the surface, and it's at the surface, but we have to be very close," Ryan said. "In contrast, if one of those whales is anywhere within an area thousands of square kilometers around our hydrophone, we'll hear them."

In February, Ryan and his colleagues published a study in the journal PLOS One, which used hydrophones, or underwater microphones, to record the songs of blue (Balaenoptera musculus), humpback (Megaptera novaeangliae) and fin whales (Balaenoptera physalus) in the Monterey Bay National Marine Sanctuary. The team then compared the acoustics data to fisheries data from the National Oceanic and Atmospheric Administration (NOAA). The scientists found that whale singing fluctuates based on food availability and that whales sang less when food resources were scarce.

The study began in 2015 at the peak of a devastating marine heatwave known as "the blob." This heatwave disrupted the marine ecosystem and left whales starving. As a result, 2015 was the year researchers heard the least amount of whale song. However, when temperatures cooled and the marine ecosystem slowly recovered, the whales found their voices again.

Related: Creepy 'biotwang' noises coming from the Mariana Trench finally explained after 10 years

In July, National Geographic reported that blue whales are going silent, which has since been repeated by multiple news outlets citing the February study. However, while the amount of whale song in the study varied from year to year, all three whale species were singing more at the end of the study period compared with the beginning. In other words, the whales weren't going silent at all; they were getting louder — or at least, being heard more often after the heatwave.

Blue whale singing rose dramatically between 2015 and 2018, dropped between 2018 and 2020, and rose again in 2021. This singing trend tracked with rises and falls in the availability of their only prey, krill. The researchers believe that when food availability is low, the whales can't put as much energy into their singing.

"In the case of blue whales especially, they can't switch prey, so they simply have to search farther and wider for the only prey they eat," Ryan said. "We can imagine that if they have to dedicate much more time and energy to foraging, then there will be less time and energy available for other behaviors."

Chemical analysis of whale skin samples confirmed that blue whales searched farther and wider for krill when there were fewer available. In contrast, humpback whales switched between krill and fish (anchovies and sardines) depending on availability. As a result, they were the only whale species that saw a continuous rise in singing over the six-year period, according to the study.

"As food resources for whales changed throughout the six-year study period, humpback whales were found to be more resilient than blue whales," Ryan said. "This is because humpback whales have a more flexible foraging strategy, feeding on different types of prey," he added.

The study's findings were consistent with a 2023 study published in the journal Ecology and Evolution, which found a reduction in certain blue whale calls off New Zealand during regional marine heatwaves in the summers of 2016 and 2018. Both studies highlight the negative effects that marine heatwaves can have on whales.

Extreme marine heatwaves have tripled over the past 80 years, with additional widespread heatwaves in 2023 and 2024. The latest whale song study covered data collected up until June 2021, so it's currently unclear what has happened since. However, while the world's oceans are getting warmer due to climate change, the whales off California haven't "stopped singing."

Ryan said that they have continued to collect data since the end of the study period and are studying those numbers right now. When asked whether the blue whales have gone silent since 2021, he replied: "Nope."

Are blue whales in decline?

Blue whales are much rarer today than they were before modern commercial whaling decimated their populations in the early 1900s. Since then, blue whale hunting has been banned and their population has been increasing, according to NOAA. But most population estimates are a few years old.

A draft of the latest NOAA U.S. Pacific marine mammal stock assessment states that there are around 1,898 blue whales in the eastern North Pacific population — the blue whales that Ryan recorded singing off California. However, that estimate is based on data collected in 2018. The global population is estimated to be between 5,000 and 15,000 adults, according to the IUCN Red List of Threatened Species, but that figure is also based on a 2018 assessment.

Editor's note: This story was amended to clarify that whale skin sample analysis revealed the blue whales searched farther and wider for krill, their primary diet, not just that they continued to feed on them.

Scientists have discovered that a glacier in the Russian Arctic is retreating extremely quickly — and its rapid retreat has exposed a graveyard of ancient whale bones.

The research expedition landed on Wilczek Island, in the far north of Russia, earlier this year to study permafrost, according to a statement from the Arctic and Antarctic Research Institute (AARI) in Russia.

Using satellite imagery, the team compared current and past positions of the glacier, Nikita Demidov, an AARI geologist, said in the statement. The scientists found that the ice cap on the island had split into two parts over a period of less than 20 years.

This glacier's decline is part of a wider shift — a study from February found that, since 2000, glaciers have lost about 5% of their ice globally.

Related: Dramatic transformation of the Arctic landscape may be permanent

The schism in the ice revealed several square miles of the island's surface, which held a large number of whale bones. Some of the skeletons are well preserved. Demidov noted that the bones are worst preserved near the seashore, where they have had longer to thaw, and are best preserved closest to the glacier.

"The paleontological find indicates an episode of extremely rapid sea level change in the area of the northernmost archipelago of Eurasia, which occurred in the last few thousand years," he said.

The expedition is being conducted from an Russian ice-strengthened vessel called Professor Molchanov and will continue through August, according to Russian state news agency TASS.

Wild orcas occasionally approach humans and offer us food, according to a new study — but scientists aren't sure why.

Researchers have documented dozens of cases of orcas (Orcinus orca), also known as killer whales, dropping prey and other sea life in front of people. In almost all of the encounters, the orcas then waited to see what humans would do with their offering, and sometimes tried to offer food more than once. These offerings included fish, some whale, birds, stingrays, seaweed and a turtle.

Researchers aren't certain what's driving this behavior, which was documented in different orca populations over a more than 20-year period. But orcas are known to share their food, according to the new study, published June 30 in the Journal of Comparative Psychology.

"Orcas often share food with each other — it's a prosocial activity and a way that they build relationships with each other," study lead author Jared Towers, the executive director of Bay Cetology, a cetacean research institute in Canada, said in a statement. "That they also share with humans may show their interest in relating to us as well."

The researchers offered a range of possible explanations for the behavior, suggesting that offering items to humans could provide opportunities for the orcas "to practice learned cultural behavior, explore or play," and potentially form relationships with us.

However, while the behavior seems altruistic, the researchers couldn't rule out that the orcas were trying to manipulate the people they approached — though it's unclear what the orcas are trying to achieve.

Erich Hoyt, a researcher at the charity Whale and Dolphin Conservation who was not involved in the study, told Live Science that the authors gave plausible reasons for the orcas sharing prey with humans.

"The study was done carefully, removing borderline cases, and the method was clearly explained," Hoyt, who also wrote "Orca: The Whale Called Killer" (Firefly Books, 2019), said in an email. "The authors are suitably careful about the conclusions and suggesting various explanations."

Related: Orcas filmed making out in the wild for first time

The researchers reported 34 sharing interactions from around the world, including off the coast of California, Norway and New Zealand. Towers and his colleagues included their own encounters with orcas, as well as those described to them in interviews. Some of the interactions were also caught on camera. The team only included interactions where the orcas approached humans of their own accord, when humans were in the sea, on boats or close to the shore, though the humans may have first put themselves in the vicinity of the orcas.

In most cases, humans ignored the orcas' offering. Some of the orcas then recovered the item and shared it with other orcas, and in a few cases, returned to offer it to the human again — even trying multiple times. On three occasions, humans returned the offering, and the orcas then offered it again, according to the study.

Orcas are intelligent and communal creatures that engage in complicated social rituals, from gently nibbling on each other's tongues to tumbling alongside each other in the marine mammal equivalent of mosh pits. This also isn't the first time orcas have interacted with people.

For example, an orca population used to hunt alongside Indigenous Australian whalers and European whalers in Australia. However, orcas got food out of those cooperative hunts, while in the new study, they were often giving it away without a clear motive.

They can also be incredibly playful animals and sometimes toy with food and other objects in their environment. For example, researchers have documented orcas tossing around and killing baby porpoises that they have no intention of eating. Some orcas famously have a penchant for attacking boats off southwestern Europe's Iberian coast, which again appears to have a playful component. However, the researchers found that the orcas in the new study usually weren't playing with the food they offered.

"With all the comments about orca play behaviour in relation to the Iberian orcas bending and breaking rudders of boats, it could be easy to dismiss these [offerings] as isolated incidents representing no more than another kind of play," Hoyt said. "But [the] authors point out that the provisioning/prey sharing happens equally between all sex and age classes, not just by the younger members who more actively engage in play."

Different orca populations have their own dialects, similar to human language, and can develop their own unique "fads," such as swimming around with dead salmon on their heads. The newly documented behavior wasn't confined to a specific population or location, but the researchers did find that it only involved orcas that typically hunt and share prey near the surface, which could help explain its origin.

All of the orcas documented in the study were generalist hunters, typically eating a range of air-breathing animals like whales, as well as fish usually found near the surface. None of the cases involved orcas that exclusively feed on fish, often at depths, despite some of these orcas being very familiar with people. Hoyt said this aspect of the study was fascinating but also logical.

"Salmon and other fish are often hunted singly, not cooperatively," Hoyt said. "The [orca] whales that hunt marine mammals, sharks and other larger prey are much more often sharing the large prey items they catch with their pods and not just because there’s plenty to go around."

Orca quiz: Will you sink or swim?

Dwarf sperm whales have an unusual way to protect themselves if they come under attack. When they feel threatened, these tiny whales release their intestinal fluid, turning the water red.

Growing up to 8 feet 10 inches (2.7 meters) long, they are the smallest species of whale. They are even smaller than some dolphins, such as Risso’s dolphins (Grampus griseus) which can reach 13 feet (4 meters) and bottlenose dolphins (Tursiops truncatus), which grow to around 12 feet (3.8 meters). These animals look so similar to pygmy sperm whales (Kogia breviceps) that it's challenging to tell the two apart. They were even believed to be the same species until 1966.

At the surface, they don't usually approach boats, which makes them very hard to study. The life of these toothed whales is typically unhurried. According to the Whale and Dolphin Conservation, they tend to travel at a steady pace, and drift gently back under the water when they’re ready to go back to deeper waters.

They only dive suddenly when they're startled. If this happens, they also release their intestinal fluid, potentially in defense or as a reaction to feeling nervous — like a squid releasing ink.

Related: Sperm whales drop giant poop bombs to save themselves from orca attack

No other whales, except pygmy sperm whales, use this tactic to escape from danger.

"Each dwarf sperm whale has a sac filled with dark liquid in its intestine," representatives from the National Oceanic and Atmospheric Administration Fisheries wrote. "The whale can release more than three gallons [11 liters] of dark, reddish-brown liquid — or ink — from this sac."

This cloud darkens the water, making it harder for the predator to see, which helps the tiny whale to make its getaway.

Their predators include large sharks and orcas (orcinus orca), and these pint-size whales are also threatened by entanglement, vessel strikes, and pollution.

Dwarf sperm whales can live to around 22 years old. Although little is known about their social behaviors, they are usually seen in small pods of no more than 16 whales.

They prefer deep waters and can dive to over 1,000 feet (300 meters) to find food. They eat a variety of deep-sea squid, octopus, crabs, and fish — using echolocation to track down their prey. They are often found near continental shelves where they have access to lots of their food sources.

Whales are a group of mammals that live in oceans. They include some of the largest animals on Earth. The blue whale is the biggest animal that has ever existed. Whales can be found in every ocean, with many species migrating long distances between their feeding and mating grounds, where they gather to have babies.

There are over 90 whale species. Some of the most famous whale species are humpback whales, sperm whales, blue whales and narwhals. Despite their name, killer whales — or orcas — are not whales. Instead, they are part of the closely related dolphin family.

Many whale species were hunted for their oil and other body parts during the 1800s and 1900s, and they almost went extinct. Even though this practice has been banned in most countries, some whale species still have very small populations and are considered vulnerable, endangered or critically endangered.

5 fast facts about whales

• Cuvier's beaked whales hold the record for the deepest-diving mammal. They can go nearly 10,000 feet (3,000 m) below the water's surface — about 10 times deeper than the Eiffel Tower is tall..
• Some whales, such as humpback whales, are known for their long and complex songs, sometimes lasting up to 22 hours.
• Whales are not fish, so they cannot breathe underwater. Instead, they use the blowholes on the top of their head to breathe air at the ocean's surface.
• Whales evolved from a deer-like land mammal called Pakicetus about 50 million years ago.
• A sperm whale's brain weighs about 17 pounds (8 kilograms) — about five times heavier than a human brain — making it the largest brain of any known animal.

Everything you need to know about whales

Whale pictures

Discover more about whales

—Humpback whales: Facts about the singers of the sea

—Will humans ever learn to speak whale?

—Why some whales go through menopause

A viral video appears to show a humpback whale gobbling up a kayaker off the coast of South America before quickly spitting him out again.

Adrián Simancas was kayaking with his father in the Strait of Magellan in Chile last Saturday (Feb. 8) when the whale burst out of the water and seemed to close its mouth around Simancas and his kayak. For a few seconds, the whale and Simancas disappeared beneath the waves.

"I thought I was dead," Simancas told The Associated Press (AP). "I thought it had eaten me, that it had swallowed me."

The whale didn't hold onto Simancas for long as he soon popped back up at the surface. Then, as the terrified kayaker treaded water, the whale hunched its spine and dove back down into the ocean. Simancas' father, Dell, caught the whole incident on video before assisting his son out of the water. The pair returned to shore unharmed, AP reported.

Related: Male humpback whale crossed 3 oceans for sex, inadvertently breaking distance record for species

Do humpback whales eat people?

Humpback whales (Megaptera novaeangliae) feed on small fish and crustaceans. To eat enough to sustain their massive size, the whales take stretchy mouthfuls of more than 5,000 gallons (23,000 liters) of seawater and filter out their prey across baleen plates — kind of like long hairy teeth that filter rather than bite. This strategy evolved for hunting small animals, not humans in kayaks.

Erich Hoyt, a research fellow at Whale and Dolphin Conservation in the U.K. and author of the Encyclopedia of Whales, Dolphins, and Porpoises (Firefly Books, 2023), told Live Science that the whale in the video almost certainly snapped up the kayaker by accident.

"It's not clear from the video whether the kayaker was entirely in the whale's mouth," Hoyt said. "He could have been partly inside but I'm sure the whale would have expelled him immediately."

This isn't the first time a whale has appeared to gobble someone up accidentally. In 2020, a similar viral video showed a humpback whale coming out of the water and closing its mouth around two kayakers in California. The kayakers were floating above a large swarm of fish when the whale came up, CBC reported at the time. The humpback immediately released the kayakers, who were unharmed in the incident.

In 2021, a lobster diver off Massachusetts estimated that he was in a humpback whale's mouth for 30 seconds before being spat out. Whale researchers suggested at the time that the diver may have also swam too close to the whale's food and been accidentally gobbled up with it.

Hoyt said that humans are too large to be swallowed by a humpback whale. Researchers have studied humpback whales with Cassin's auklet seabirds (Ptychoramphus aleuticus) in their stomachs, which were presumably accidentally swallowed. However, those birds are only about 9 inches (23 centimeters) long, Live Science previously reported.

While humpbacks don't eat people, they have occasionally injured humans when they've felt threatened. In 2020, a humpback mum — likely trying to protect her calf — charged swimmers in Australia and sent two to the hospital. However, the species is better known for occasionally saving other animals from predators like killer whales (Orcinus orca) than harming humans.

Killer whales

Simancas was talking to his father about killer whales shortly before the incident with the humpback whale took place (killer whales also live off the coast of Chile). He told AP that he thought the whale might have been a killer whale at first. However, even if that were the case, a human in the ocean has little to fear from a killer whale.

"There are no cases of a wild killer whale killing and eating a human either," Hoyt said.

Some orcas have a habit of attacking boats in southwest Europe, and the species has killed humans when kept in captivity, but there's only one confirmed case of a wild orca biting a human. That unlucky person was a surfer in California in 1972, who the orca probably mistook for a seal.

We don't know exactly when the first animals on Earth appeared, but it's thought to be around 700 million years ago. Around 541 million years ago, at the start of the Cambrian period, hundreds of thousands of new species appeared within a span of about 20 million years — an event known as the Cambrian explosion. Since then, millions — or possibly billions — of species have come and gone. Scientists estimate that 99.9% of all creatures that ever lived have gone extinct.

Researchers think there are now around 7.7 million animal species living on Earth, with thousands more discovered every year. But species are also going extinct at an alarming rate, with many likely vanishing before they've even been formally recognized. Many scientists even say we're entering a sixth mass extinction.

How much do you know about the animals currently living on our planet? Take our quiz to find out. If you need a hint, hit the yellow button. Good luck!

More science quizzes

—Mammoth quiz: Test your knowledge of the ice age beasts

—Evolution quiz: Can you naturally select the correct answers?

—Orca quiz: Will you sink or swim?

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

—Crocodile quiz: Test your knowledge on the prehistoric predators

Endangered southern right whales can live twice as long as scientists thought, a new study shows. These whales often reach 130 years old, and may even reach up to 150 years old, the study found.

Southern right whales (Eubalaena australis) are found throughout the Southern Hemisphere but were heavily hunted until the 1960s, when the International Whaling Commission began to ban commercial whaling. People in the whaling industries considered them the "right" kind of whales to hunt because they move slowly, float when dead and have a high yield of lucrative oil and whalebones.

Previously, scientists thought southern right whales had a life expectancy of around 70 years. But these marine mammals are closely related to bowhead whales, and the longest-living mammal ever recorded was an Alaskan bowhead (Balaena mysticetus) estimated to be 211 years old.

"Given everything else we knew about the life history of these species, I hypothesized that they [the Southern right whales] should live longer," study co-author Greg Breed, a quantitative ecologist at the University of Alaska Fairbanks, told Live Science.

However, estimating the longevity of whales can be difficult.

Scientists typically use annular growth layers on teeth, which, like tree rings, are laid down yearly. Many baleen whales, however, do not have such growth layers. And even if they do, tissue wear and tear, and lack of samples could skew the estimation.

But a bigger challenge is that, commercial whaling only ended about 60 years ago. So whales older than that would have survived many decades of intense whaling to become centenarians. It's likely few individuals reached their full lifespans.

To get around these challenges, Breed and his team analyzed whale tracking data of southern and North Atlantic right whales (Eubalaena glacialis) collected over four decades. From 1979 to 2021, scientists led by Peter Best at the University of Pretoria in Cape Town surveyed female southern right whales on the south coast of Africa by photographing them each year. From this survey, the scientists behind the new study identified 2,476 female individuals, 139 of which had known birth years. Breed and his team used these data to construct a survivorship curve. They noted the age and rate at which an individual disappears from the population. From there, they could estimate the fraction of a population surviving to a certain age.

"It's the same thing that the Social Security Administration uses to evaluate how long someone, who's now 65, what their average lifespan would be from that point, rather than from birth," Breed said.

The researchers compared these results with the North Atlantic right whale records collected around the same time and made available by the North Atlantic Right Whale Consortium, a nonprofit conservation group.

The analyses, described in a study published Dec. 20, in the journal Science Advances, revealed that southern right whales have a median lifespan of 70 to 75 years. One in 10 individuals was predicted to survive past 130 years old, confirming Breed's initial hypothesis. In comparison, North Atlantic right whales have relatively short lives with a median lifespan of 22 years, and only a few survive past the age of 45.

"Not because they're biologically very different, but because they have been experiencing a much higher degree of anthropogenic or manmade mortality than the southern right whales," Breed said. North Atlantic right whales are frequently entangled in fishing gear, especially lobster pots and crab pots that are fixed on the bottom of the ocean, he said.

Even with the current estimate, southern right whales only live half as long as bowheads. The researchers think this is linked to the right whales living in places devoid of sea ice.

"There's reason to think that living in the ice could contribute to longer lifespan," Breed said. For example, Orcas (Orcinus orca) or killer whales, which hunt both bowheads and southern right whales, are very averse to going into sea ice. "So the bowheads could always get into the sea ice, and the killer whales wouldn't follow them," Breed said. As sea ice disappears, bowheads may no longer be able to avoid predation.

Understanding an animal's lifespan affects the way we think about conservation, especially their reproduction pattern and their potential longevity post-whaling, Breed said. In the future, he and his team would like to investigate the population of old individuals that survived whaling and study how whale populations recover to pre-whaling levels.

A male humpback whale crossed at least three oceans in search of sex, a new study shows.

The whale's journey is the longest great-circle distance between two sightings ever recorded for the species (Megaptera novaeangliae), scientists said. Great-circle distance refers to the shortest distance between two points on Earth as measured on the planet's spherical surface.

Beginning off the coast of Colombia in the eastern Pacific Ocean and ending off the coast of Zanzibar in the southwest Indian Ocean, the whale's odyssey took it 8,106 miles (13,046 kilometers) across the globe, the researchers said.

The whale likely swam eastward from Colombia, riding on prevailing currents in the Southern Ocean and potentially visiting humpback whale populations in the Atlantic Ocean, said study co-author Ted Cheeseman, a doctoral student at Southern Cross University in Australia and director of Happywhale, an image database where the researchers collected evidence for the study.

"This was a very exciting find, the kind of discovery where our first response was that there must be some error," Cheeseman told Live Science in an email. Together with the astounding mileage, one of the most important findings from the study was that the whale dropped in on several humpback whale populations along the way, exploring farther afield than any other humpback whale known to science, Cheeseman said.

Related: Watch heartbreaking footage of humpback whale with missing tail in Washington state

Humpback whales usually follow very consistent migration patterns, moving between feeding grounds in cold waters near the poles and breeding areas closer to the tropics. The whales are known to swim more than 5,000 miles (8,000 km) in the north-south direction every year, but they don't tend to travel far in the east-west direction and generally don't mix with other populations.

The cross-ocean journey observed in the new study shows that humpback whale migrations are more flexible than researchers previously thought. While scientists have occasionally recorded similar migrations before — such as the case of a female humpback whale that swam 6,100 miles (9,800 km) from Brazil to Madagascar between 1999 and 2001 — the male in the new study has set a new distance record while traveling from one breeding area to another.

"We've been able to document novel behavior which provides important insight into [humpback whales'] ecology," study lead author Ekaterina Kalashnikova, a biologist working with the Tanzania Cetaceans Program and the Barazuto Center for Scientific Studies in Mozambique, told Live Science in an email.

The discovery is based on photographs the researchers took between 2013 and 2022, and which they subsequently posted on Happywhale. The pictures showed the same sexually mature male in two locations off Colombia, and then five years later in the Zanzibar Channel, each time in the company of a competitive group — a group of whales in which a female is closely guarded by a male "principal escort" and other males compete for access to her, Kalashnikova said.

The motivation for the journey was probably sex, with the male in question increasing his chances of reproducing by mingling with members of another breeding population. Other reasons for the whale's unusual adventure could be to do with environmental shifts that impact the distribution of food; climate change; and humpback whale population growth, which boosts competition between males during the feeding and breeding seasons, according to the study.

The research was published Tuesday (Dec. 10) in the journal Royal Society Open Science.

Researchers have finally identified the source of mysterious noises coming from the deepest ocean trench. The odd sounds, described as "biotwang" noises, sound a bit like sci-fi starships, and are actually whale calls from Bryde's whales (Balaenoptera edeni). The whales may use the calls to locate one another like a giant game of Marco Polo, researchers say.

Scientists first detected the unusual noises in 2014 while using underwater gliders to carry out an acoustic survey of the Mariana Trench — the world's deepest ocean trench, which spans more than 1,500 miles (2,400 kilometers) south of Japan and has a maximum depth of 35,876 feet (10,935 meters).

The biotwang sound can be broken down into two distinct parts: first, a low, grumbly sound that reverberates through the deep; and second, a high-pitched, metallic ringing that researchers have likened to the sounds made by spaceships in Star Trek and Star Wars.

The sounds initially stumped scientists. But in 2016, researchers revealed that biotwang was most likely a call from large baleen whales, such as blue whales (Balaenoptera musculus) or humpback whales (Megaptera novaeangliae). However, the sounds did not match any known whale calls.

In the new study, published Wednesday (Sept. 18) in the journal Frontiers in Marine Science, researchers were finally able to prove that Bryde's whales were making the noises, thanks in part to new artificial intelligence (AI) tools that sifted through over 200,000 hours of audio recordings containing various ocean sounds.

Related: Hidden DNA found in blue whales reveals they've been mating with other species — and their hybrid offspring

Researchers strongly suspected that Bryde's whales were behind the biotwang when they spotted 10 of the cetaceans swimming near the Mariana Islands and recorded nine of them making the distinctive noise.

"Once, it's a coincidence. Twice is happenstance. Nine times, it's definitely a Bryde's whale," study lead author Ann Allen, an oceanographer at the National Oceanographic and Atmospheric Administration's (NOAA) Pacific Islands Fisheries Science Center, told Scientific American.

But to conclusively prove that the Bryde's whales were the ones making the calls, the team matched the occurrence of the noises to the migration patterns of the species, which meant sorting through years of audio recordings captured by monitoring stations across the Mariana Archipelago and its surroundings.

They sped up that process by using AI to turn the biotwang into images, known as spectrograms, that could be easily differentiated from other noises by a machine learning algorithm.

The study also found that biotwang could only be heard in the northwest Pacific, despite Bryde's whales roaming across a much wider area, suggesting that only a specific population of the whales is making the noise.

The data also showed a spike in biotwang noises during 2016, when a rise in ocean temperatures caused by an El Niño event caused an increase in the number of Bryde's whales visiting the area.

It is still unclear why these calls sound so bizarre but researchers have a hunch over why they are being made.

"It's possible that they use the biotwang as a contact call, a sort of 'Marco Polo' of the ocean," Allen told Popular Science. "But we need more information before we can say for sure."

A whale whose tail appears to have been torn off by fishing debris has been spotted off the coast of Washington state. While the whale is managing to adapt right now, it will likely die from exhaustion and starvation soon, experts say.

Aerial drone footage shows the humpback whale (Megaptera novaeangliae) missing its iconic lobed fluke, which is responsible for propulsion while swimming.

"It's very disturbing," Jessica Farrer, lead responder and research director at The Whale Museum in Friday Harbor, told Live Science. "It's such a big majestic animal and it's missing a very important part of its body and on some level we know that we are the ones — humans that is — that caused it."

Related: Whale with broken back spotted near Mexico after suspected ship collision will likely die

The whale likely lost its tail fluke because of long-term entanglement in fishing lines or other debris.

"Their flukes are massive and our oceans are full of lines so it's not uncommon at all for humpbacks to pick up line and trail with it," Farrer said.

The whale, which has been named Catalyst, was first seen on July 5 on the east side of Swindle Island, then again on July 10 near Campbell River, according to a Facebook post from San Juan County Marine Mammal Stranding Network — a program run by The Whale Museum.

On July 23 it was spotted again off the coast of Lopez Island when a drone recorded the humpback whale using its pectoral fins to push itself along, before the whale revealed its missing fluke as it attempted to dive.

Despite its injury, Catalyst has traveled a distance of around 370 miles (600 kilometers) since the first sighting.

"It was traveling at a normal speed, around 3-4 knots [3.5 to 4.5 mph, or 5.5 to 7.5 km/h], it was diving and it was doing what humpbacks do, and it managed to make it from Campbell river all the way down to the San Juan islands," Farrer said. "Talk about the little whale that could."

Whales rely on their tail fluke for communication with other whales in the form of tail slaps, and for propulsion during deep dives to forage for food.

While it can swim, "it's likely not able to forage efficiently enough to sustain itself and has zero hope of migrating so it will probably stay within the region," Farrer said.

Without a tail fluke, the whale will likely die due to starvation or exhaustion, Farrer said, but added the marine mammal might adapt to its new swimming technique in the meantime.

"Initially the whale will start to scull [propel itself] with its pectoral flippers but eventually it will start using its peduncle [the muscle where the tail fluke connects to the body] in a kind of side to side motion," Farrer explained.

Entanglement is a threat to large whales worldwide. According to estimates from The International Whaling Commission, 300,000 whales die from entanglement in fishing gear each year.

A mysterious dead whale that recently washed up on a New Zealand beach may belong to the world's rarest cetacean species, spade-toothed whales, which are so elusive they have never been seen alive. If this is the case, the newfound specimen will give scientists a rare chance to study the creatures we know next to nothing about.

Beachgoers discovered the 16.5-foot-long (5 meters) carcass July 4 on the shore near Taieri Mouth — a village in the Otago region of New Zealand's South Island. Wildlife experts from the country's Department of Conservation (DOC), recovered the remains and took DNA samples, which have been sent to the University of Auckland for analysis, according to a DOC statement.

Researchers from DOC and the Museum of New Zealand Te Papa Tongarewa believe the animal is a spade-toothed whale (Mesoplodon traversii). However, they will not know for sure until the DNA samples are analyzed, which could take "several weeks or months," DOC representatives said. The remains are currently being preserved in cold storage.

Spade-toothed whales belong to a group known as beaked whales, which look like a mix between whales and dolphins. Beaked whales are the deepest-diving mammals on Earth and are capable of holding their breath for hours at a time, which makes them extremely hard to find and track.

If confirmed, the newly washed-up whale will be the sixth known spade-toothed specimen found in the last 150 years, of which only two others have been fully intact. To date, there have been no confirmed live sightings of the species.

"Spade-toothed whales are one of the most poorly known large mammalian species of modern times," Gabe Davies, a DOC coastal operations manager for Otago, said in the statement. "From a scientific and conservation point of view, this is huge."

Related: 10 creatures that washed up on the world's beaches in 2023

Spade-toothed whales were officially described in a 2002 study, which revealed that three whale bones found in New Zealand and Chile between 1873 and 1993 shared the same DNA that was unknown to science. The first intact specimens were found in 2010 when a suspected mother and calf washed up dead at Opape Beach in New Zealand's North Island.

Almost nothing is known about the species. However, researchers believe they probably share characteristics with other beaked whales from the genus Mesoplodon, such as extremely rare Sowerby's beaked whales (Mesoplodon bidens), which spend most of their time diving in the deep sea to hunt for squid, according to Whale and Dolphin Conservation (WDC).

Spade-toothed whales likely live exclusively in the Southern Hemisphere and are probably only found in the South Pacific Ocean, according to WDC.

If the new specimen is a spade-toothed whale, this will be the first chance that researchers have to dissect the species because the other intact specimens that washed up at Opape Beach were buried before genetic analysis confirmed their identity, AP News reported — meaning the opportunity to study them was lost.

Any dissection of the specimen will be carried out under the supervision of the local rūnaka — a Māori tribal council, DOC representatives wrote. This will be done to honor a non-legally-binding treaty signed by Māori leaders and several Polynesian Indigenous groups in March, which recognizes whales as "legal persons."

Japan's commercial whaling activities could soon expand to include fin whales, government officials announced last week.

The move, which experts have heavily condemned, would increase the number of whale species Japan hunts in its territorial waters to four; the other three species are the Bryde's whale (Balaenoptera edeni), the sei whale (Balaenoptera borealis) and the minke whale (Balaenoptera acutorostrata). 

For now, it appears the decision to include fin whales hinges on public approval of changes to the country's marine resource management policy, according to the marine conservation organization OceanCare. 

The fin whale (Balaenoptera physalus) is the second-largest whale species on Earth, after the blue whale (Balaenoptera musculus). Fin whales are named for the distinctive fin that protrudes from their lower back, and they can grow up to 85 feet (26 meters) long. They are found across all the world's oceans. In the first half of the 20th century, however, fin whale populations nose-dived due to commercial whaling and they are still recovering from the shock, according to the International Whaling Commission (IWC), which regulates modern whaling practices.

In 1982, the IWC introduced a moratorium on commercial whaling that went into effect in 1986. Although Japan stopped commercial hunts after 1986, the country resumed taking whales for what it said was scientific research one year later. In 2019, Japan withdrew from the IWC and began catching whales commercially once again, although its whaling activities are now restricted to the country's territorial waters in the North Pacific Ocean.

Related: Hidden DNA found in blue whales reveals they've been mating with other species — and their hybrid offspring

On May 9, officials announced that Japan could start hunting fin whales soon. "Whales are important food resources and should be sustainably utilized, based on scientific evidence," Yoshimasa Hayashi, Japan's minister for foreign affairs, said at a news conference.

According to the IWC's most recently published whaling data, Japan took 25 sei whales, 187 Bryde's whales and 58 minke whales in 2022. In recent years, the country has also imported fin-whale meat from Iceland, according to OceanCare. 

The International Union for Conservation of Nature (IUCN) lists fin whales as vulnerable to extinction globally, although the species was still listed as endangered as recently as 2018 and is considered as such under the Endangered Species Act of 1973. However, there is insufficient data to pinpoint the status of local populations in the North Pacific, according to the IWC. 

Without reliable population estimates, Japan's move to hunt fin whales is an "appalling step backward" for ocean protection, Clare Perry, a senior adviser at the Environmental Investigation Agency (an international NGO that investigates environmental crime and abuse), said in a statement. 

"Fin whales are one of Earth's great carbon capturers and should be fully protected, not least so that they can continue to fulfill their critical role in the marine environment," Perry said.

The announcement comes after Japan unveiled a brand-new whaling "mother ship" in March. The factory ship, called the Kangei Maru, can handle and process large whales, including fin whales, "which could tie Japan into decades more of this destructive, unsustainable, inhumane and outdated industry," Perry said.

Whether or not Japan goes ahead with its plans to hunt fin whales depends on the outcome of a public consultation of the country's newly drafted whaling policy — but it seems likely the changes will be approved, according to OceanCare.

Sperm whales blasted a "big dark bubble" of poop to prevent an impending orca attack off the southern coast of Western Australia.

Scientists witnessed the clever defense strategy unfold Tuesday (March 19) during a tourist excursion in Bremer Canyon, a whale-watching hotspot off the coast between Albany and Hopetoun. They described seeing a "cloud of diarrhea" permeate the water, and this rarely seen defense mechanism seemed to help the sperm whale pod escape what could have been a fatal attack by at least 30 killer whales, ABC News Australia reported. 

"It's called defense defecation," Jennah Tucker, a marine biologist with Oceans Blueprint, a marine and environmental sciences research organization, who was on the charter boat, told ABC. When the animals defecate, she said, they pass their huge tails through their poop to drive away or confuse attackers.

As the event unfolded, onlookers noticed a large, "dark bubble" pop up to the water's surface. At first, they thought it was blood from one of the sperm whales, potentially a small calf. But when the team later reviewed footage of the plume, they realized it was actually whale poop.

"Because [a] sperm whale's diet consists mostly of squid, they actually have this really reddish colored poo," she said.

Related: Why some whales go through menopause

In this demonstration of defense defecation, the pod formed a circle with their heads together, and the whales fanned their tails in unison — forcing their excrement toward the unsuspecting orcas.

"This is called a rosette, another defensive mechanism they use when they're under attack," Tucker said.

Tucker told ABC she noticed that the sperm whales looked distressed and exhausted. However, their fecal warfare worked, and the orcas swam off in search of fresher waters. It was in the midst of this mayhem that researchers saw the big, blobby poop bubble rise to the water's surface.

There have been only a few documented instances of orca attacks on sperm whales, largely due to the sheer size differential between the two species.

"Sperm whales are considered an apex predator, and historically, it was thought that they were pretty much immune to killer whale attacks," Tucker said. "It's actually pretty adventurous for orcas to try to take on sperm whales. They're punching above their weight."

Beluga whales change the shape of their heads in order to express themselves and communicate with one another, researchers have discovered. They are the only toothed whales known to engage in this behavior, and scientists are now hoping to understand the role of this unique behavior in their social interactions. 

Many mammals use facial expressions to communicate emotion and intent, but cetaceans are largely expressionless. While they do have facial muscles, their contractions are concealed by turgid, rubbery skin. In comparison, primates, dogs, pigs and other animals known to communicate using their faces have highly flexible facial skin.

According to a new study published March 2 in the journal Animal Cognition, belugas (Delphinapterus leucas) get around this by altering the shape of their melons — the bulbous protrusions at the front of their heads — to communicate with other whales. 

These protrusions are composed of fatty tissue and are known to amplify auditory signals that are key to the whales' social interactions. But the scientists found that they may also serve as visual signifiers. 

Related: Why some whales go through menopause

"Melon shapes seem to function as visual displays, with some characteristics of intentional communication," the researchers wrote in the paper. "This ability could yield adaptive benefits to belugas, given their complex social structure and hypothesized mating system that emphasizes pre-copulatory female mate choice."

The researchers identified five different types of melon shape — flat, lift, press, push and shake. Footage shows the shifting shapes during social interactions. 

When the melon is flattened, it squashes downward, eliminating the curve at the top. When it is lifted, it extends above the skull, appearing taller than it does when relaxed. When the melon is pressed, it flattens along the top of the skull. When it is pushed, it extends forward above the upper jaw. And during the shake pattern, it wobbles back and forth.

In total, the researchers observed 2,570 expressions of these shapes in the study population — two male and two female belugas at Mystic Aquarium in Connecticut. Additional observations were made at MarineLand Canada in Ontario. Alterations to the shape of the melon mostly occurred in social contexts ranging from playful and amorous to aggressive, though they also occurred in non-social contexts. 

"Melon shapes occurred 34 times more frequently during social interactions (1.72 per minute) than outside of social interactions (0.05 per minute)," the researchers wrote. "Melon shapes occurring during social interactions were performed within the line of sight of a recipient 93.6% of the time."

Males changed the shape of their melons three times as frequently as females, often during mating displays but also during sociosexual and aggressive encounters with other males. 

The flat and shake patterns were most common during courtship displays. Flat and push patterns were most commonly observed during male socialsexual play, in which males interact in ways that elicit visible sexual arousal, affiliative encounters, where the whales form groups and swim alongside each other, as well as mouthing behaviors, which can be either aggressive or playful.

It is not yet known whether these facial expressions are produced as a reflex or whether they are intentional displays — or both. While they were cataloged in specific behavioral contexts, the exact meanings of the expressions also remain a mystery, the scientists said.

This research may be a crucial first step in understanding visual communication in belugas. Scientists already have a rough understanding of their sophisticated vocal repertoires, which include whistles, calls and echolocation clicks used in hunting. Analysis of their visual signaling capacities may provide further insight into how these highly intelligent mammals navigate their social interactions.

Editor's note: The headline of this article has been corrected after previously stating the behavior had not been documented before. 

Menopause evolves in toothed whales, like orcas and belugas, by lengthening their lives without changing how long they can reproduce. That allows older females to care for grandchildren without competing with their own daughters and sisters, a new study reveals.

The study, published today (March 13) in the journal Nature, is the first to examine menopause across several species.

"This is a piece of work that very much needed to be done," Megan Arnot, an evolutionary anthropologist at University College London, who was not involved in the study, told Live Science.

Living for an extended period after menopause is very rare in nature, with humans and five species of  toothed whales as the only mammals known to possess this trait. Chimps in one wild population also go through menopause, though whether it is encoded genetically or just an accidental byproduct of an optimal environment is unclear.

At first glance, menopause seems to violate the rules of evolution.  In order to have the most shot at passing on genes, it would make sense for an individual to breed until the end of its life.

So why did some species evolve menopause? According to the "grandmother hypothesis," females stop reproducing in order to help their children and grandchildren. This would indirectly help females pass on their genes by increasing the survival of their grandchildren.

Related: Chimps go through menopause. That could shed light on how it evolved in humans.

As for how menopause evolves, there are multiple ideas. One, called the "live-long hypothesis" posits that animals simply live longer over time, while their reproductive lives stay the same. Toothed whales are an interesting test case because menopause evolved independently multiple times.

"What we wanted to do with this study was leverage this repeated evolution to ask some really general questions about how and why menopause evolves," lead author Sam Ellis, a psychologist at the University of Exeter in the U.K., told Live Science.

To test different theories on how and why menopause evolves, the researchers looked at data collected by generations of scientists to reconstruct the life history, the total lifespan and the reproductive lifespan of as many species of toothed whales as possible. Then, they compared the data from species which go through menopause and the species that don't.

Females from the five species of toothed whales that have evolved menopause have a lifespan about 40 years longer than expected for species of their size, while their reproductive lifespan is the same as that of comparable-size species. These findings support the "live-long" hypothesis.

The researchers also showed that females from species with menopause, thanks to their longer life, are able to spend much more time with their offspring — showing that there is an important role for grandmothers helping the next generations. Furthermore, by not reproducing anymore, older females don’t go into competition with their own family members.

Together, the findings suggest that “The extended post-reproductive lifespan has been the target of evolution — it is a strategy," Ellis said.

How this translates to humans is unclear. "We don’t know that it's definitely the same way it evolved in humans," Arnot said, "but it’s certainly a best guess at the moment."

However, it provides supporting evidence that there is a "common pathway by which menopause evolves," in both whales and humans, Ellis said.

But it's worth being cautious in interpreting the results, Rebecca Sear, a professor of population and health at the London School of Hygiene and Tropical Diseases, who was not involved in the study, wrote in an accompanying commentary for Nature News and Views, as "studying whale demography is not easy […] The data therefore contain biases and might involve small sample sizes”. That's because the data often looked at populations of stranded whales, which may not be representative of the age distribution of healthy populations.

"Research on menopause in humans has tended to focus mainly, although not exclusively, on searching for evidence of helpful grandmothering, and has found this in abundance," she wrote.

But that doesn't mean menopause actually evolved to provide this benefit.

"Contemporary grandmothers might help grandchildren either because menopause evolved to create helpful grandmothers, or because menopause means that older women have no choice but to invest in grandchildren rather than children."

Around 7,000 humpback whales in the North Pacific Ocean may have starved to death following the disastrous effects of a marine heat wave, a new study reveals.

From 20 years' worth of data, researchers found that a 20% drop in the North Pacific humpback whale population coincided with a marine heat wave dubbed "the blob" — an event that was responsible for record-breaking mass mortalities of multiple seabird species around the world. 

In the 20th century, global populations of humpback whales (Megaptera novaeangliae) were under threat from commercial whaling. An estimated 31,865 humpback whales were killed during the years between 1900 to 1976, dropping the population of humpback whales in the North Pacific to an estimated 1,200 to 1,600 individuals at the end of commercial catches in 1976.

In the new study, published Feb. 28 in the journal Royal Society Open Science, scientists used automated image recognition artificial intelligence (AI) created by Happywhale, a database with thousands of photographs of humpback whale tails sourced from researchers and the public to find out if populations have rebounded.

The AI identified 30,484 individual humpback whales over 132,684 encounters from the photographs of their tail flukes. 

Related: Kelping is a 'global phenomenon' sweeping the world of humpback whales, scientists say

This data allowed the team to work out population changes from the past 20 years. It revealed a positive recovery between 2002 to 2012, with the population growing at an average rate of 5.9% per year.

However, further analysis revealed a massive decline from 2012 to 2021 as numbers dropped from around 33,488 individuals to 26,662.

This drop coincided with the emergence of "the blob" — a patch of water in the Pacific Ocean linked to changes in the climate. In 2013, when the blob was first detected, ocean temperatures were 4 to 10 degrees Fahrenheit (2.2 to 5.6 degrees Celsius) above average. According to Science, it grew to cover an area of ocean spanning 1.5 million square miles (4 million square kilometers), stretching from the Gulf of Alaska to Mexico. 

The heatwave persisted for 3 years, causing toxic algal blooms, distribution changes of fish species, countless crashes in commercial fishing and mortalities of marine life. The Northeast Pacific returned to cooler conditions at the end of 2016.

"Warmer waters are less productive, like a farm with less nutrients available to grow crops," Ted Cheeseman, co-founder and director of Happywhale and lead author of the study, told Live Science in an email. 

Marine heat waves kill off organisms at the bottom of the food chain, causing a domino effect that lowers the abundance of food for small animals and then larger ones."Whales expecting to be able to get fat … on krill, anchovies, herring and other bait fish were instead suffering from starvation," Cheeseman said.

Concerns for the stability of humpback whale populations continue to grow as climate change increases ocean temperatures. "Today's extreme may become the normal state in 20 years," Cheeseman said. "If that happens, the heatwave of the future may mean genuinely unlivable oceans." 

Scientists experienced an "incredibly rare event" last week when they saw a gray whale cruising through New England's coastal waters.

The gray whale (Eschrichtius robustus) was believed to be extinct in this part of the Atlantic Ocean; the species has not been spotted there in more than 200 years, according to a statement from Boston's New England Aquarium.

The gray whale is known for its mottled gray body and supreme size — females top out at 49 feet long (15 meters) and weigh 90,000 pounds (41,000 kilograms), on average. It lacks a dorsal fin; instead, it has a dorsal hump on its lower back, according to the National Oceanic and Atmospheric Administration.

While conducting aerial surveys on March 1, researchers from the aquarium noticed the lone whale swimming 30 miles (48 kilometers) south of Nantucket, Massachusetts. The animal, which appeared to be hunting, "dove and resurfaced," enabling those on board the plane to photograph the whale in action. The scientists had an idea of what they were seeing, but they didn't know for sure until they returned to the aquarium to review the images.

"I didn't want to say out loud what it was, because it seemed crazy," Orla O'Brien, associate research scientist at the New England Aquarium's Anderson Cabot Center for Ocean Life, said in the statement.

Related: Scientists finally figure out why hundreds of gray whales keep washing up dead along US coast

O'Brien shared her photos with fellow researchers, who confirmed that her suspicions were correct.

"My brain was trying to process what I was seeing, because this animal was something that should not really exist in these waters," Kate Laemmle, a research technician at the aquarium, said in the statement. "We were laughing because of how wild and exciting this was — to see an animal that disappeared from the Atlantic hundreds of years ago!"

While gray whales are common in the Pacific Ocean, the last recorded sighting in this part of the Atlantic occurred in the 18th century. In the past 15 years, only five of the creatures have been spotted in Atlantic and Mediterranean waters, including a rare sighting in December off the coast of Florida. Scientists think this could be the same whale. 

Experts are unclear as to why the whale traveled so far north, but they think climate change could be partially to blame. That's because the Northwest Passage, a sea lane in Canada connecting the Atlantic and Pacific oceans, has been "regularly ice-free " in recent years, partly due to rising global temperatures," according to the statement.

"These sightings of gray whales in the Atlantic serve as a reminder of how quickly marine species respond to climate change, given the chance," O'Brien said in the statement. 

For the first time ever, researchers have documented penetrative sex between two humpback whales. What’s more, both whales were male.

A private vessel spotted the adult whales off the Hawaiian island of Maui in January 2022. Citizen scientists on board the boat noticed one of the animals was an unusual, brownish color and deployed cameras underwater to record the encounter. What they captured is the first known case of a male humpback whale (Megaptera novaeangliae) inserting its penis into another male's genital slit.

"This is the first report of penetration by a humpback whale, and the first report of sexual activity between two male humpback whales," researchers wrote in a study published Tuesday (Feb. 27) in the journal Marine Mammal Science. 

The whales swam in circles around the boat for 30 minutes, with one of the humpbacks (Whale B) seemingly pursuing the other (Whale A), according to the study. Whale A looked emaciated, had a significant jaw injury and was covered in whale lice (Cyamus boopis) — parasites that indicate poor health and are the probable cause of the skin discoloration noted by citizen scientists at the start of the encounter. Whale B, on the other hand, appeared healthy and strong.

Related: Kelping is a 'global phenomenon' sweeping the world of humpback whales, scientists say

Whale B also had its penis extruded from its usual hiding place inside the genital slit during the entire encounter. "Whale B repeatedly approached from the rear of Whale A and penetrated the second whale, appearing to hold Whale A in place with its pectoral fins," the researchers wrote.

In response to Whale B's advances, Whale A contorted its body into an "S" shape — a posture which previous research suggests humpbacks in Hawaii adopt when they feel threatened or stressed.

"It is possible that the use of this posture by Whale A meant that this behavior was unwelcome, but that Whale A lacked the energy to engage in avoidance strategies," the researchers wrote in the study. "It was slowly attempting to swim away from Whale B but was not making any sudden or powerful movements and did not dive out of sight at any point."

After penetrating Whale A several times, Whale B dove and did not reappear, according to the study. Whale A remained at the surface for a few minutes before also plunging out of sight. It is unclear what caused Whale A's jaw injury, but the researchers suggested it may be the result of a collision with a ship.

Male-male sex in cetaceans — a group of marine mammals that includes whales, dolphins and porpoises — is well documented for common bottlenose dolphins (Tursiops truncatus) and several other species. Research suggests cetaceans engage in such homosexual activity to establish or reinforce dominance among males, to learn or practice reproductive behaviors, to form social alliances and even to reduce social tensions. 

Related: Orcas are learning terrifying new behaviors. Are they getting smarter?

Whale B may have mistaken Whale A for a female, the researchers suggested, or it could have been trying to reinforce their social relationship. But the sexual behavior may also have been "an expression of dominance over a weak and injured competitor," they wrote in the study.

While this is the first documented case of homosexual penetration in humpback whales, a similar incident reported in 1998 described a male humpback whale extruding its penis as it swam near the corpse of another male that had died shortly before.

"It is striking that the only two observations of such behavior in the scientific literature involve ailing or deceased whales," the researchers wrote in the new study. "Whether such behavior would occur between two healthy males is unknown."

Critically endangered North Atlantic right whales are getting smaller, which is impacting their ability to breed, scientists have discovered. 

In a study published Wednesday (Jan. 28) in the journal Royal Society Open Science, researchers analyzed decades of data and found that smaller females had fewer babies. 

"We provide strong evidence that the declining trend in right whale calving probability is associated with the decreasing body size of individuals in this population," lead author Enrico Pirotta, an ecologist at University of St Andrews, told Live Science. "This adds to previous evidence indicating that their health is also declining."

The researchers reviewed data from the North Atlantic right whale consortium collected between 1970 and 2020, including measurements taken using aerial photos. They used a statistical model to understand the relationship between a sexually mature female's length, health, survival, and ability to reproduce. 

They found that the animal's length cubed — indicative of body volume — was the main factor influencing the likelihood of having calves, the odds of which decreased in smaller females. On average, a 46 foot (14 meter) female had a 56% probability of giving birth while a 36 foot (11 meter) female had just a 14% chance. Length has a much larger impact on the probability of calving than health or random variables .

Whales use stored reserves of organic substances called lipids to give them enough energy to reproduce. "Being smaller means that a female can accumulate less energy in absolute terms, which in turn could affect her ability to successfully breed," Pirotta said.

Related: Hidden DNA found in blue whales reveals they've been mating with other species — and their hybrid offspring

North Atlantic right whales (Eubalaena glacialis) are the most endangered of all the species, which also includes North Pacific right whale (Eubalaena japonica) and Southern right whale (Eubalaena australis). The study focused on the critically endangered species because its vulnerability to human threats means effective protections are needed urgently — once decimated by whalers, there are just 356 individuals believed to be alive today. 

North Atlantic right whales have been getting shorter since 1981, as a result of stressors such as climate change. While the mechanisms behind their decreasing sizes are unclear, it is thought to be linked to the reduced availability of nutrients. Size reductions in response to climate change have been documented in terrestrial and marine species, the authors wrote. 

According to the National Oceanic and Atmospheric Administration (NOAA) 17 North Atlantic right whale calves have been born this season. To stop the species' decline, 50 or more would need to be born each year. 

"For one of the most endangered large whales on the planet, every single North Atlantic right whale calf is vital to avoid extinction," Julia Singer, a marine scientist at the ocean conservation group Oceana who was not involved in the study, told Live Science. 

"This year alone, the U.S. East Coast has become a graveyard for North Atlantic right whales after two young whales were struck by boats, another juvenile died from a painful entanglement in fishing gear, and two newborn calves are presumed dead after going missing," Singer said. 

During calving season (November to April), vessel speed limits are put in place in the southeastern U.S., and ships must travel under 10 knots (around 11.5 miles per hour) to protect mothers and calves from boat strikes. Oceana is calling for the U.S. government to update the rules to include smaller vessels, which have also been known to hit right whales. 

"This study shows the need for stronger protections to reduce the constant risks and stress North Atlantic right whales face every day from navigating a jungle of vertical fishing lines and speeding boats in their migration path," Singer said. 

An eerie image captures whale skeletons resting in their watery grave after being killed by hunters off Greenland. The whales had been taken to shore, stripped of the skin, blubber and meat, before being dragged back into the sea. There, they remain in the shallows to be consumed by marine invertebrates.

The photograph, taken by Alex Dawson, has won the Underwater Photographer of the Year 2024 competition after being selected from over 6,500 entries. "Whale Bones," was chosen as the winner because it "invites us to consider our impact on the great creatures of this planet," panel chair Alex Mustard said in a statement emailed to Live Science. 

"A very arresting image right from the start; for me this got bigger and better with every viewing," Mustard said. "The diver’s suit and torch give it a 'visiting alien' feel, the composition flows effortlessly and takes your eye on the right journey to tell the story." 

Dawson, from Sweden, took the photograph off Tasiilaq in Greenland, a town with a population of around 2,000 people that sits on the coast of the North Atlantic, roughly 66 miles (106 kilometers) south of the Arctic Circle. In the image, a freediver approaches one of two whale skeletons from above, with a gap in the ice above and a flashlight illuminating the bones. 

Related: Polar bear sleeping on tiny iceberg drifting in Arctic sea captured in heartbreaking photo

Minke whales are the smallest of the baleen whales — species that feed by sieving plankton through plates in their mouths. Common minke whales (Balaenoptera acutorostrata) are listed as of least concern by the International Union for Conservation of Nature Red List. Because of their size, they were generally considered too fast and small by the commercial whaling industry, and were only hunted when the numbers of other, larger species were depleted. The industry largely ended in the 1980s, however some minke populations are still killed as part of annual hunts. In east Greenland, an average of nine minke whales are killed each year. 

"In eastern Greenland the local hunters bring their catch and share it among each other," Dawson said in the statement. "From a stable population of over 100,000 minke whales in the North Atlantic the hunters of Tasiilaq typically take less than a dozen." Dawson said families from the town gather at low tide to cut off the skin, blubber and meat.

"Almost all the whale is consumed, however the skeleton is pulled back into the sea by the next high tide and the remains can be found in shallow waters where various marine invertebrates and fish pick the bones clean," he said. 

The Underwater Photographer of the Year competition was launched in 2015. This year, Dawson's image was the overall winner from 130 finalists. A selection of the other winning and highly commended images can be seen below. 

If marine mammals want to sleep, they can't just close their eyes and drift away for the night, as they need to intermediately surface for air. Nor can they float at the water's surface and slumber, because that exposes them to predators and heat loss. So how do marine mammals get any shut-eye without putting themselves at risk?

One solution is to shut down one half of their brain at a time. Called unihemispheric sleep, it's one way marine mammals, such as dolphins, can get some rest while in open water.

"Unihemispheric sleep is really valuable to these animals because it allows them to maintain a low level of activity while still sleeping half of their brain at a time," Patrick Miller, a biologist at the University of St Andrews in the U.K., told Live Science.

Dolphins are the best-studied marine mammals capable of this style of sleeping. Brain scans on captive dolphins show that while one hemisphere is in slow-wave, deep sleep, the other hemisphere is alert, allowing the animals to literally sleep with one eye open. This style of sleeping is common in cetaceans — the group of mammals that includes dolphins, whales and porpoises — but it's not unique to them. Many bird species are known to use unihemispheric sleep, often allowing them to doze while flying.

But according to Miller, birds and dolphins use their half-brain sleeping technique for different purposes. For instance, in a flock of birds, many of the ones on the outside of the group keep the eye facing away from the flock open, to watch for predators. But dolphins do the opposite: While sleeping, they tend to keep the eye open that faces the rest of the pod, likely to avoid becoming separated.

Related: Why do horses sleep standing up?

Not all cetaceans seem to be capable of unihemispheric sleep. Some use bihemispheric sleep, in which both hemispheres of the brain fall asleep, just like humans and most other mammals do.

"It's really difficult to measure brain activities for animals out at sea that you're not able to capture, like a sperm whale, blue whale or a humpback whale," Miller said. "In that case, behavioral records are our best indicator of sleep behavior."

In those cases, researchers can affix tags to the animals to monitor their behavior. A 2008 study led by Miller used suction tags attached to sperm whales (Physeter macrocephalus) to show that they sleep out in the open ocean for short bouts. The whales make shallow dives beneath the surface, slow their swim speed to a stop, and pitch lazily upward. Their upward pitch is likely due to the buoyant oil, known as spermaceti, in their heads.

While sleeping, whole pods of whales can be seen nose-up, just below the ocean's surface. During this time, the animals are completely unresponsive, which suggests they are in a form of deep sleep. However, the animals can rest only about 20 minutes underwater before they need to come back up for air. Once the whale has caught its breath, it slinks below the surface for more rest, and may continue this behavior for up to 3.5 hours.

Northern elephant seals (Mirounga angustirostris) are bihemispheric sleepers as well and snooze in similar short bouts. A 2023 study led by Jessica Kendall-Bar, a postdoctoral researcher at the Scripps Institution of Oceanography, a department of the University of California, San Diego, was able to, for the first time, monitor brain activity in a sleeping mammal at sea. Kendall-Bar and colleagues found that the seals dive to a depth of around 1,000 feet (300 meters), at which point their brains slow down and enter rapid eye movement (REM) sleep. Once in REM sleep, the seals flip upside down and spin in a slow circle while continuing to sleep.

"Seals sleeping in the ocean were upside down 100% of REM sleep time, suggesting that just like us, they become paralyzed during REM," Kendall-Bar said in a YouTube video describing the research.

Likely due to predation risk, elephant seals limit their total sleep time at sea to just around two hours per day, "rivaling the record for the least sleep among all mammals, which is currently held by the African elephant (about 2 hours per day)," the researchers wrote in the study.

Blue whales in the Atlantic Ocean are harboring a previously unknown and potentially alarming level of hybrid DNA, a new study shows. The findings hint that whale hybrids are much more reproductively viable than previously realized.

Blue whales (Balaenoptera musculus) are the world's largest animal, capable of reaching an astonishing 110 feet (34 meters) long, around three times longer than a school bus. 

The number of these giants plummeted in the early 20th century due to extreme levels of commercial whaling. As a result, blue whales are currently listed as endangered by the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species, although their numbers are starting to rebound worldwide. Of the four subspecies of blue whale, B. musculus musculus, which is found in the North Atlantic and North Pacific, is one of the most at-risk.  

In a new study, published Jan. 6 in the journal Conservation Genetics, researchers analyzed the genomes of B. m. musculus in the North Atlantic for signs of inbreeding, which could impede the recovery of this group. 

The researchers created a "de novo" genome for this population, meaning it was created from scratch, by piecing together bits of DNA from different individuals. The team then used this new genetic blueprint as a template to further analyze the full or partial genomes of 31 individuals from across this population's range.

"This is a long, laborious process akin to assembling a huge jigsaw puzzle with no picture on the box for guidance," study co-author Mark Engstrom, an ecological geneticist at the University of Toronto, told Live Science in an email. But once the puzzle has been solved, it becomes much easier to do it again and again, he added.

They found that each of the sampled whales had some fin whale (Balaenoptera physalus) DNA lurking within their genomes. Around 3.5% of the group's DNA came from fin whales on average.

Related: Nuclear bomb detectors uncover secret population of blue whales hiding in Indian Ocean

Scientists have long known that blue whales and fin whales can reproduce to create hybrids of the two species, despite blue whales being around 85 tons (77 metric tons) heavier on average, according to The New York Times. These hybrids are sometimes referred to as "flue" whales and often look like unusually large fin whales with the coloration and jaw structure of blue whales, according to a 2021 study. 

Until recently, it was assumed that these hybrids were infertile and could not have offspring of their own, similar to most other hybrid animals. However, a 2018 study revealed that at least some of these hybrids could successfully reproduce with blue whales.

Researchers believe hybrid whales have been reproducing with blue whales, resulting in "backcrossed" offspring with mostly blue whale DNA and some fin whale DNA. This type of DNA transfer from one species to another via interbreeding is known as introgression. 

The new study team had suspected they may find fin whale DNA among the genomes they sequenced. "But the amount of introgression between the species that we found was unexpected and much higher than reported previously," Engstrom said.

Similar studies on fin whales have found no evidence that the species have inherited any blue whale DNA via introgression, Engstrom said. So it seems that only blue whales are capable, or perhaps willing, to reproduce with these hybrids.

"We don't know why introgression appears unidirectional," Engstrom said. However, it could be because there are many more fin whales than blue whales, he added. 

There is also little evidence that introgression between fin whales and blue whales happens in any other part of the world. "As far as we know, this is a phenomenon in the North Atlantic only," Engstrom said. Although why that might be is unclear, he added.

There is no current evidence that carrying fin whale DNA negatively impacts blue whale individuals. However, Engstrom is concerned that if introgression continues, it could reduce the amount of blue whale DNA across the population, which could make these whales less resilient to adapting to new challenges, such as human-caused climate change. 

The genomes also revealed that there was much less inbreeding between North Atlantic blue whales than expected. The researchers found that there is a significant gene flow between whales from the western Atlantic, around North America, to the eastern Atlantic near  Europe, which is likely caused by western whales following the North Atlantic current eastward to feed. 

This is good news because it means the population is more connected and, therefore, more genetically diverse and resilient to changes, Engstrom said. "This gives me hope that with sustained conservation efforts, Atlantic populations can recover."

A whale with a broken backbone has been spotted off the coast of Baja California Sur, Mexico after a suspected ship strike. An image of the humpback whale (Megaptera novaeangliae) taken with a drone camera shows its spine badly deformed at the tail — an injury that will likely prove fatal.

The whale was spotted in December, 2023 by underwater photographer and videographer Alexander Schmidt, from Apex Ocean Divers, off Cabo San Lucas. He shared footage of the whale with the Pacific Whale Foundation, a Hawaii-based nonprofit. 

Scientists initially thought the whale could be Moon, a humpback that had swum 3,000 miles (4,800 kilometers) with a broken back from Canada to Hawaii. But closer analysis by Stephanie Stack, chief biologist at the Pacific Whale Foundation, confirmed they were different whales. 

"As with Moon, I suspect this is likely to be a fatal injury," she told Live Science in an email. "Whales are highly resilient creatures, but severe injuries like this can significantly reduce their chances of survival in the wild."

Related: Scientists finally figure out why hundreds of gray whales keep washing up dead along US coasts

A broken back would cause difficulty swimming, affecting the whale's ability to migrate, feed, come to the surface for air and evade predators, Stack said. "Humpback whales operate on an extremely tight energy budget and an injury that affects their ability to move normally could have catastrophic consequences," she added. "Beyond the physical challenges, a broken back is likely to cause significant stress and pain for the affected whale." 

How the whale off Baja California Sur got injured is unknown, but collisions with ships are a significant cause of whale deaths, with estimates suggesting thousands are killed every year, according to research by non-profit Friend of the Sea. In March, 2023, a 56-foot-long (17 meters) fin whale (Balaenoptera physalus) was spotted struggling to swim off the coast of Spain due to a severely broken back. Experts said the injury was also likely caused by a ship collision and that the whale would probably slowly starve to death.

Whale mortality is a significant problem off the U.S. West Coast as several endangered species frequent these waters. As a result, the National Oceanic and Atmospheric Administration (NOAA) put speed regulations in place so vessels over 65 feet (20 m) long can't travel over a maximum of 10 knots (11.5 mph, or 18.5 km/h) at certain times of the year. 

But research suggests slower speeds are not enough — a study published in 2021 found that 95% compliance with lower speed rules would reduce whale deaths only by between 25% and 30%. 

"We know that vessel collisions are one of the most significant and widespread threats that whales are facing today," Stack said. "Cases like these are tragic, but we hope they can be used to raise awareness and prevent future deaths." 

Humpback whale "conversations" provide valuable insight on how humans may one day communicate with life beyond Earth, new research claims. 

Researchers from the SETI Institute, University of California Davis and the Alaska Whale Foundation recently "conversed" with a humpback whale named Twain using an underwater speaker and recorded a humpback "contact" call. Twain responded to the researchers' call by matching the interval variations between signals of each playback call over a 20-minute period. 

If you're having a Star Trek flashback, yes, this is awfully reminiscent of that one film in which the crew receives alien whale transmissions that can only be decoded underwater. And in fact, mirroring our sci-fi fantasies, this demonstration of interspecies communication has implications for the search for extraterrestrial intelligence (SETI), according to a statement from the SETI Institute.

"We believe this is the first such communicative exchange between humans and humpback whales in the humpback 'language,'" Brenda McCowan, lead author of the study from U.C. Davis, said in the statement.

Much like how astronaut crews simulate missions to Mars or the moon on Earth, the Whale-SETI team is studying humpback whale communication systems to better understand how to detect and interpret signals from outer space. Their findings can be used to develop filters that can be applied to any extraterrestrial signals received, according to the statement. 

"Because of current limitations on technology, an important assumption of the search for extraterrestrial intelligence is that extraterrestrials will be interested in making contact and so target human receivers," Laurance Doyle, coauthor of the study from the SETI Institute, said in the statement. "This important assumption is certainly supported by the behavior of humpback whales."

Twain's response to each playback call showcases a sophisticated level of understanding and interaction. The humpback whale approached and circled the team's boat upon hearing the contact call played via an underwater speaker. Matching the interval variations between each call mirrors a human-like conversational style, according to the study.

Related: Orcas are learning terrifying new behaviors. Are they getting smarter?

"Humpback whales are extremely intelligent, have complex social systems, make tools — nets out of bubbles to catch fish — and communicate extensively with both songs and social calls," Fred Sharpe, co-author of the study from the Alaska Whale Foundation, said in the statement. 

Therefore, working with humpback whales offers a unique opportunity to study intelligent communication in non-human species. The team will apply principles of information theory to develop filters that can aid in processing extraterrestrial signals and the search for intelligent life beyond Earth.

Originally posted on Space.com.

A ghostly white lump of rotten flesh in the shape of a mermaid recently washed ashore on an island in Papua New Guinea — and experts baffled.

The strange sea creature was likely a marine mammal, but its exact origins are unclear, experts told Live Science.

The mysterious mass was discovered Sept. 20 by locals on Simberi Island — a small volcanic island with a population of around 1,000 people in the Bismarck Sea in New Ireland Province, according to a Facebook post by New Irelanders Only (NIO). 

It is known as a globster — an unidentified organic mass that washes ashore. The origin of these mystery lumps is hard to pin down because much of the corpse has rotted away and most are missing body parts that have fallen off at sea. In this case, most of the creature's head and large chunks of its flesh are missing.

There is no information on the size and weight of the corpse because it was not properly measured before locals buried it, NIO representatives told Live Science. And no one collected DNA samples, which makes a proper identification almost impossible.

Related: 10 bizarre creatures that washed ashore in 2022 

Experts were also unable to identify it from the images alone. 

Helene Marsh, an environmental scientist at James Cook University in Australia, told Live Science it looks like a marine mammal. "After that it is anyone's guess," she added.

Sascha Hooker, a marine mammal expert at the University of St Andrews in Scotland, narrowed it down further. "It looks like a very decomposed cetacean to me," she told Live Science. Cetaceans, or whales and dolphins, are known to turn this color when their skin falls off, she added.

The most common cetaceans in the area are short-finned pilot whales (Globicephala macrorhynchus), spinner dolphins (Stenella longirostris), pantropical spotted dolphins (Stenella attenuata) and sperm whales (Physeter macrocephalus), according to a 2021 study in the journal Pacific Science. 

Erich Hoyt, a researcher at Whale and Dolphin Conservation in the U.K. and author of several books on cetaceans, agrees that the globster could be a small whale. However, he believes that it could also be a dugong, or "sea cow," that is known to graze on sea grasses in shallow waters in Papua New Guinea.

Other experts also suggested it could be one of the pudgy marine mammals, which have previously inspired stories of mermaids. "My best estimate is that it might be a Dugong," said Jens Currie, chief scientist of the Pacific Whale Foundation in Hawaii. Based on what's left of the head, it looks too wide to be a cetacean, he added. And "the amount of blubber also indicates a marine mammal and not a shark," Currie said.

But not everyone thinks that the globster was a marine mammal. 

Gavin Naylor, a marine biologist at the University of Florida who runs the International Shark Attack Files, thinks the remains could be from a large shark. Although "it is a little weird that all of the skin appears to have rotted off," he told Live Science. 

Other shark experts disagree.

"At first, I was leaning toward a large shark, but now that I've spent a bunch of time looking at this, I am more confident it is a cetacean" due shape of the tail and location of the flippers, said Gregory Skomal, a marine biologist at the University of Boston and head of the shark program at Massachusetts Marine Fisheries. The vertebrae, which are exposed in one of the images, also look more like a whale's backbone than a shark's cartilaginous spine, he told Live Science.

Skomal also spotted what "looks like a trachea," or windpipe, hanging from the animal near where its head was. If true, this would rule out a shark. 

But whatever it is, it has likely "been dead for weeks," Hoyt said.

A strange series of mass deaths among gray whales in the northeastern Pacific Ocean may finally have an explanation, with scientists linking Arctic sea ice levels to the major die-off events. 

Three mortality events have struck gray whales (Eschrichtius robustus) living off the coast of North America since the 1980s, reducing the population by 15% to 25% each time, according to a new study. In total, more than 2,000 gray whales are known to have died. The first mass die-off took place between 1987 and 1989 and was the largest in magnitude, killing at least 700 whales. Reporting structures and survey efforts only expanded in the 1990s, however, meaning the number of strandings associated with this mortality event could be an underestimate, according to the study. The second took place between 1999 and 2000, killing 651 whales. 

The latest die-off began in 2019 and saw more than 70 gray whales wash up dead in just six months. It is ongoing and — as of Sept. 26, 2023 — a total of 688 whales have died. What caused each of the events was unclear. 

"These are extreme population swings that we did not expect to see in a large, long-lived species like gray whales," study lead author Joshua Stewart, an assistant professor at Oregon State University's Marine Mammal Institute, said in a statement.

Related: Could an impending rise in solar storms cause more whales to strand?

Commercial whaling until the mid-20th century drove the population of North Pacific gray whales to near-extinction, but it has since bounced back and currently numbers around 14,500 individuals, according to the statement. Scientists previously thought this successful recovery meant the whales were dying off periodically as their numbers exceeded what their habitat and prey could provide for.

But changing conditions and fluctuating sea ice levels in the Arctic may better explain what the National Oceanic and Atmospheric Administration (NOAA) termed "unusual mortality events," according to the new study, published Oct. 12 in the journal Science.

Sea ice cover and the amount of food available for gray whales may dictate how the population fares. Higher-than-usual ice cover in some years may block passage to the Bering and Chukchi seas, where the whales spend the summer months feasting on fatty crustaceans before migrating southward again. "When the availability of their prey in the Arctic is low and the whales cannot reach their feeding areas because of sea ice, the gray whale population experiences rapid and major shocks," Stewart said.

Gray whales quickly rebounded from the first two mortality events. But the most recent die-off is ongoing since 2019 and has cast us into "uncharted territory," Stewart said. 

Unlike the two previous events, a historic loss of Arctic sea ice could be to blame for the latest gray whale die-off. That's because sea ice hosts a carpet of algae on its underside, which decays and showers the seabed with food for bottom-dwellers, including the whales' preferred crustaceans. 

"With less ice, you get less algae, which is worse for the gray whale prey," Stewart said. Melting sea ice also frees up passage for strong currents that sweep away the sediment and leaves bottom-dwelling crustaceans and other creatures homeless. "All of these factors are converging to reduce the quality and availability of the food [gray whales] rely on," he said.

Climate change might be the reason this mortality event is dragging on for longer than the previous two, Stewart said. "What we're seeing is much more of a bumpy ride in response to highly variable and rapidly changing ocean conditions," he said.

While climate change could mean there is less food for gray whales, it probably won't put the northeastern Pacific population at risk of extinction, Stewart said. But "an Arctic Ocean that has warmed significantly may not be able to support 25,000 gray whales like it has in the recent past," he added.

Humpback whales frolicking in seaweed — a behavior known as "kelping" — is more widespread than previously thought and constitutes a "global phenomenon," new research has found.

Kelping was first observed in 2007, and scientists have described the behavior before — but only as isolated events. It turns out, humpbacks across the world enjoy the leafy caress of seaweed on their skin, both as a form of play and as a potentially soothing body scrub. 

"It's something they do together as a social event or by themselves," study lead author Olaf Meynecke, a research fellow at Griffith University's Coastal and Marine Research Centre in Queensland, Australia, told Live Science. "They put the seaweed on their head and roll around in it; they try to move it around with their pectoral fins as well."

For the new study, researchers examined 95 social media posts documenting kelping in humpback whales, spanning across the North-East Pacific and North Atlantic to the west and east coasts of Australia.

Related: Orcas and humpbacks clash in a violent melee of breaching and biting 

And while the term "kelping" suggests a preference for kelp — large brown algae that grow in relatively shallow waters near the shore — humpback whales (Megaptera novaeangliae) interact with different types of seaweed, Meynecke said.

"The whales don't seem to be that picky," he said. "Whatever was available in the region was what the whales interacted and played with."

Humpbacks belong to a group of filter-feeding whales known as baleen whales, which are known to interact with objects in their ocean habitat. Humpback whales sometimes play with logs and driftwood, as well as with fishing gear and jellyfish, according to the new study, published Sept. 15 in the Journal of Marine Science and Engineering.

Seaweed probably feels soft and pleasant against their skin, Meynecke said. Along their jaws and around their head, humpbacks have sensory, highly innervated hairs that may be stimulated when they brush against seaweed.

"It's very clear from drone footage that the whales are targeting the kelp and sometimes leaving a pod of whales to go straight for the kelp," Meynecke said. 

Kelping also may have therapeutic benefits, as it could help humpbacks shed parasites and bacteria that colonize their skin. "Just that rubbing will get rid of some of those little guys," Meynecke said. Seaweed is thought to have antimicrobial properties, but more research is needed to assess whether this applies to creatures that hitchhike on the whales.

Humpback whales sometimes bite down on seaweed and pull it underwater before letting go of it again, which may serve to scrub the insides of their mouths, Meynecke said. "They're grabbing it with their mouths — which is really interesting, because they're baleen whales that don't have teeth, and for them to bite something is not a natural instinct," he said. 

But parasites could be beating humpbacks at their own game by latching onto patches of seaweed and jumping across when whales come for a scrub, Meynecke said.

This wouldn't be the first evidence of these whales doing skin care. Earlier this year, for the first time, researchers filmed humpbacks treating themselves to a full body scrub on the seafloor. 

Playing in patches of seaweed could also enhance learning and strengthen social ties when several whales get involved, according to the study. "This is about coordination, mobility and the enjoyment of having something to play with," Meynecke said.

But climate change could ruin the whales' fun by shifting the distribution of seaweed, especially kelp, Meynecke cautioned. "Kelp has been under extreme stress with ocean warming," he said. The proliferation of species that feed on kelp, such as sea urchins, is also worrying, he added, because "they can turn an amazing, beautiful forest of kelp into a complete desert." 

An unusually explosive peak in the sun's solar cycle is fast approaching, which could spell trouble for a surprising group of animals — whales. 

Past research showed that some larger whale species are more likely to get lost and accidentally beach themselves during solar storms, which become stronger and more frequent during the solar maximum — the most active phase of the sun's roughly 11-year cycle. This is likely tied to whales' ability to navigate using Earth's magnetic field, which becomes harder when solar storms smash into our planet.

A "surprising number of animals" can perceive the Earth's magnetic field — an ability called magnetoreception — including lobsters, fish, sea turtles, migratory birds and some insects, said Kenneth Lohmann, a biologist at the University of North Carolina who has extensively studied magnetoreception. Some animals use it to orient themselves in a particular direction, like using a compass. But for others, it acts like a GPS system that lets them know exactly where they are and where they need to go, he told Live Science.

At least two whale species — gray whales (Eschrichtius robustus) and sperm whales (Physeter macrocephalus) — use magnetoreception. But studying exactly how it works for these cetaceans is difficult because scientists can't capture and study them in the lab, Lohmann said.  Other whale species, such as humpback whales (Megaptera novaeangliae), likely also use magnetoreception, but establishing this has proved equally tricky, he added. 

But it is becoming clearer that, however magnetoreception works in whales, solar storms majorly mess with it.

Related: Mystery orcas with bulbous heads wash up dead in unexplained mass stranding

In 2020, scientists discovered that migrating gray whales were more than four times more likely to beach themselves during periods of increased sunspot numbers on the sun between 1985 and 2018. (Sunspot numbers are a key indicator of solar activity. The number of sunspots sharply increases in the lead-up to and during a solar maximum.)

And in 2017, researchers linked an unusually high concentration of sperm whale strandings from early 2016 to a series of solar storms that occurred around the same time.

Researchers believe that increased radio frequency noise, which often accompanies solar storms, likely disrupts the whales' magnetic receptors, "effectively blinding them from being able to sense the magnetic field," rather than impacting the magnetic field itself, said Jesse Granger, a sensory biologist at Duke University and lead researcher of the 2020 study. This becomes more likely during solar maximum when solar storms become more frequent, she told Live Science. 

The next solar maximum was initially forecast to begin sometime in 2025 and be weak compared with past solar cycles. However, earlier this year, Live Science reported that the solar maximum could arrive sooner and be more active than previously predicted, possibly arriving  as soon as the end of 2023 or early 2024. 

If the upcoming solar cycle is more active than expected, it could pose a greater threat to whales, Granger said. Not only will there be more solar storms but they will also be stronger, which means there is a higher likelihood that their effects will be powerful enough to disrupt whales' magnetoreception, she added.

Lohmann agreed that a more active solar maximum will likely have a greater effect on whales and could lead to an increase in the number of strandings.

Related: Extremely rare white humpback whale washes up dead on Australian beach

However, there is still an element of uncertainty surrounding this area of research. 

"Our work is purely correlative, and correlation does not equal causation," Granger said. In other words, just because strandings occur more often during periods of increased sunspots doesn't mean for certain that storms are causing the strandings. 

Other possible causes could be noise pollution from commercial shipping and naval exercises, or diseases, such as bird flu, Granger said. More work is needed to strengthen the link between solar activity and whale strandings, she added.

Whales may not be the only animals to be impacted by the upcoming solar maximum. 

Homing pigeons and migratory birds are more likely to become lost if there are solar storms while they are flying, Lohmann said. Fish like salmon also likely rely on magnetoreception to make long migrations to spawning grounds, but scientists don't know whether solar storms disrupt their navigation, he added. 

A pint-size whale that lived 41 million years ago in what is now Egypt was the smallest of its kind and died young, leading researchers to name it after the ancient Egyptian pharaoh Tutankhamun, who died at age 18.

Called Tutcetus rayanensis, the newly described species of basilosaurid, an extinct family of fully aquatic cetaceans, was the smallest known basilosaurid whale ever to exist, according to a study published Thursday (Aug. 10) in the journal Communications Biology. The ancient whale measured approximately 8 feet (2.5 meters) long and weighed about 412 pounds (187 kilograms) — about the size of a modern-day adult tiger (Panthera tigris). 

While larger than humans, T. rayanensis was downright "miniature" when measured alongside other basilosaurids, which ranged from 13 to 59 feet long (4 to 18 m), according to a statement.

Paleontologists discovered the whale's fossilized remains five years ago in the Fayum Depression, a desert basin near the Nile River in Egypt. After analyzing the extinct marine mammal's preserved skull, jaw, teeth and fragments of vertebrae, they determined that because the bones within its skull and vertebrae had already fused and its adult teeth were still emerging, it was nearing adulthood when it died, according to the study.

The researchers couldn't help but notice the similarities between T. rayanensis' early death and the boy pharaoh who died in 1323 B.C.

Related: This colossal extinct whale was the heaviest animal to ever live

"King Tut died young as well," study co-author Hesham Sallam, a paleontologist at the Institute of Global Health and Human Ecology at The American University in Cairo, told Live Science. 

The animal's well-preserved sharp teeth not only provided insight into its age at death but also hinted at what the whale may have eaten in the prehistoric Tethys Ocean.

"We were lucky to have a complete set of T. rayanensis' lower teeth and discovered that it was almost-mature but still subadult," study co-author Abdullah Gohar, a doctoral candidate in the Department of Zoology at Mansoura University in Egypt, told Live Science. "Its teeth had very smooth enamel, which is an indication of very soft feeding mainly on fish, squids, octopus and other not-fast-moving prey."

Because its permanent molars emerged before its permanent premolars —  a common occurrence in mammals with shorter life cycles — the researchers deduced that the miniature whale may have reached sexual maturity at an earlier age but also died earlier than other basilosaurids, according to the statement.

"T. rayanensis lived fast and died fast," Gohar told Live Science. "This could also be an adaptation to climate change."

If that's the case, the whale's small stature and short life cycle could be a response to the Lutetian Thermal Maximum, a warming event that occurred about 42 million years ago and saw animals shrink, according to the study.

A pearly white baby humpback whale has been filmed off the coast of Australia, prompting speculation about whether it is an extraordinarily rare albino whale. Others also wondered whether the calf could be the offspring of "Migaloo", a completely white whale like the mythical Moby Dick.

Drone operator Jaydyn Mathewson spied the pale whale in late July, gliding alongside its mother through the turquoise waters off the northern tip of New South Wales. Humpback whales migrate to this stretch of eastern Australia’s coast between June and August to mate and give birth, having traveled north from the rich feeding grounds of Antarctica, where they return between September and November.

Humpback whales (Megaptera novaeangliae) are almost completely dark gray to black and typically feature white blotches only on their bellies, but in the video, the calf's milky-white tail and fins can be seen gleaming in the sunlight.

However, experts are hesitant to attribute the calf's features to albinism. This rare genetic condition is caused by a recessive gene which disrupts the cells’ ability to make melanin, the substance that produces pigmentation in skin, hair, and eyes. This results in pale skin and pinkish eyes.

Related: Whale sighting in Australia hints at 'extremely unusual' interspecies adoption

While rarely documented, lighter hues aren't unheard of in newborn whales, Wally Franklin, a cetacean research and marine scientist at The Oceania Project, a non-profit dedicated to the research and conservation of dolphins and whales, told Live Science. "They are born with a down covering which appears very light and whitish in the light and as a result they are mistakenly considered to be albino," he said. "The initial down covering dissipates usually within a week and the normal black and white pigmentation is established."

Photographers also captured footage of two other baby "Moby Dicks" off the state of New South Wales in recent weeks. One was spied near Burrewarra Point at the southern tip of the state by a drone in late June, almost seeming to glow beneath the waves. The other was spotted in mid-July at Lennox Head in the north, where it was filmed sidling up to its mother until it slipped out of view beneath her protective belly. 

Determining whether these youngsters have albino traits would require observation over time as well as skin samples. But whales confirmed to have albinism are extremely rare. "The reality is that the only albino in the eastern Australian humpback whale population is the very well known 'Migaloo,'" Franklin said. 

Migaloo, whose name means "White Fella" in several Australian Aboriginal languages, was first spotted in 1991 off the country's west coast, which falls along another humpback whale migration route from Antarctica. It took almost 15 years to confirm his albino status from sloughed off skin cells, which showed he has the genetic hallmark of albinism. 

Albinism can increase sensitivity to sunlight and cold and make creatures more vulnerable to predators. Yet Migaloo has survived to adulthood and is a healthy whale. "The observational evidence is that he gets along with other humpbacks in a very normal way," Franklin said.

Migaloo hasn't been spotted since 2020, though the sighting of a pale adult humpback off Australia's Queensland coast earlier this year raised hopes that it could be him. Even so, for the white calves to be his, Migaloo would need to have mated with a female who also carried the rare mutation for albinism.

What's more likely, Franklin said, is that the sightings are the result of a rare good news environmental story: conservation has led to the resurgence of the Australian humpback population in the last 60 years, from a few hundred in the 1960s to tens of thousands today. This means there’s an uptick in the number of young being born in the calving waters off of eastern Australia. 

"Hence there are increased sightings of newborns occurring along the coast," Franklin said. "With so much interest in the humpback migration, we are both sighting and receiving increased coverage of these beautiful light colored new born calves, which is wonderful."

Marine mammals like whales and seals need highly specialized bodies to dive far below the waves and withstand the crushing pressure of the deep ocean, while going without oxygen for an extended period of time.

That’s because mammals, unlike fish, can only get oxygen by breathing the air at the surface of the ocean. 

"For anything that breathes air and then forages at depth, you've got this real disparity that most animals don't have to deal with," Nicola Quick, a marine scientist at Duke University in North Carolina, told Live Science. "One of their critical resources, air, is in one place — and their other critical resource, which is food, is in another place." 

But which mammal is able to dive the deepest? 

That title likely belongs to Cuvier's beaked whales (Ziphius cavirostris), mid-size whales that live in temperate and tropical waters around the globe. In 2010, researchers started strapping satellite trackers to these animals off the coast of California to record their movements, and they uncovered the whales' astonishing diving abilities.

Related: This colossal extinct whale was the heaviest animal to ever live

One of the eight whales they tagged dove down 9,816 feet (2,992 meters), equivalent to about 32 times the height of the Statue of Liberty. What's more, the whales could dive for a long time — one stayed underwater for more than 2 hours.

In 2020, Quick and her colleagues witnessed a new record after observing a Cuvier's beaked whale staying underwater for 3 hours and 42 minutes. That dive was excluded from the official results of their study because it came after exposure to sonar, which could have affected the whale's behavior — but the study noted that a dive this long may indicate "the true limits of the diving behavior of this species."

Quick's paper noted three things that would allow whales to accomplish such long dives. First, their blood has high concentrations of the proteins myoglobin and hemoglobin, which lets them store a lot of oxygen. Whales can also limit how much blood flows to the outer parts of the body to make sure the vital organs get enough oxygen.

Second, the whales need a slow metabolism so they don't use up all their oxygen at once, the study noted. And to help conserve energy, the animals seem to glide a lot while swimming, Quick noted.

Lastly, the whales probably need a way to quickly buffer out the lactic acid their muscles produce while swimming — although Quick said it's unclear how they might do this . 

Deep-diving mammals also have to be able to withstand the pressure experienced when thousands of feet underwater. The hardest things to keep open in high pressure are the lungs, since lungs are pockets of air that could easily collapse under intense pressure. But diving mammals have the ability to flatten out their lungs as they dive to reduce the amount of air space they have to keep open under pressure.

Quick said that scientists believe Cuvier's beaked whales are foraging for food while they dive, but researchers don't know for sure what they're eating in the deep — though one 2017 paper suggested it's mostly squid.

Other marine mammals can also dive deep below the surface. Southern elephant seals (Mirounga leonina), for example, have been found diving to around 6,560 ft (2,000 m) deep — as have sperm whales (Physeter macrocephalus).

A colossal ancient species of whale that lived 39 million years ago was a true heavyweight, weighing more than double a blue whale and likely earning itself the title as the heaviest known animal to have ever lived. 

The newly described basilosaurid (a family of extinct cetaceans), called Perucetus colossus, eclipsed blue whales (Balaenoptera musculus) in sheer weight with an estimated body mass of between 187,000 to 750,000 pounds (85,000 to 340,000 kilograms). It had an estimated body length of about 66 feet (20 meters) — longer than a lane at a bowling alley, according to a new study published Wednesday (Aug. 2) in the journal Nature.

Paleontologists discovered the partial skeletal remains of the monstrous marine mammal 30 years ago in what is now Ica Province in southern Peru. Since then, they've unearthed 13 vertebrae, four ribs and a hip bone, according to a statement.

"[One of my co-authors] was looking for fossils in the desert in Peru and saw an outcropping of bones," lead author Eli Amson, a paleontologist and curator of fossil mammals at the Stuttgart State Museum of Natural History in Germany, told Live Science. "Digging out the fossils took a lot of time because of their sheer size. Each vertebra alone weighs 150 kilos [330 pounds]."

Related: 'Truly gigantic' Jurassic sea monster remains discovered by chance in museum

Researchers can only estimate how enormous P. colossus was using the limited number of bones they unearthed, as much of the animal's remains have decayed over time — including all of its soft tissues. 

However, the bones they did recover were very dense, meaning they weighed a lot. To compensate for this heavy skeleton, the team believes the whale's soft tissues were likely lighter in weight than the bones, offsetting its heavy skeleton and helping it become more buoyant, according to the study.

As a result, P. colossus likely had a very weird appearance. The team likened it to a modern manatee, but with a tiny head, an enormous body and little arms and legs. "It might have looked much weirder than we think," Amson said. 

"In terms of weight, P. colossus was definitely bulkier than a blue whale. But the overall body length was shorter than the blue whale [and measured] 20 meters (66 feet). It's hard to estimate exactly how much blubber and soft tissues surrounded its skeleton, and so we went with a rather conservative approach with our size estimates," Amson said.

But that weird appearance may have helped it to remain buoyant and enabled it to glide slowly through the water, similar to manatees (genus Trichechus), the researchers wrote in the study.

Not only does P. colossus shatter our perceptions of what the world's heaviest animal might have looked like, it also challenges what we know about the evolution of cetaceans. This discovery means they reached their peak body mass 30 million years earlier than originally thought.

"P. colossus completely changes our understanding of evolution and extreme gigantism in cetaceans," Amson said. "It was most likely a slow traveler and a shallow diver. We're not sure what it ate since its head and teeth didn't survive. It's only speculative, but we think it spent most of its time at the bottom of the ocean not burning a lot of energy to get its sources of food."

Jeremy Goldbogen, an associate professor of oceans with the Hopkins Marine Station at Stanford University in California, who was not affiliated with the paper, said that studying P. colossus can offer new insights into the evolution of marine giants.

"The described species, Perucetus colossus, was clearly a large animal, and it had a heavy skeleton," he told Live Science in an email. "Was it bigger than a blue whale? Maybe it was and maybe it wasn't. I would argue that [the] more important questions relate to the evolution of entire groups of related species and the biology underlying when and why they got big."

The specimen is currently being housed at the Natural History Museum in Lima.

Wildlife experts were recently forced to abandon the autopsy of an enormous fin whale corpse that washed up on a beach in Ireland after sounds coming from the giant creature's gut suggested that it could explode if they cut it open.

The dead fin whale (Balaenoptera physalus), which was around 62 feet (19 meters) long, washed up in the early hours of July 9 at Baile Uí Chuill Strand, in County Kerry, the Irish Examiner reported. The cause of death is unknown but the hefty whale had likely been dead for up to three weeks before it washed ashore, based on the level of decomposition. 

Experts from the Irish Whale and Dolphin Group (IWDG) arrived at the scene to collect samples for a necropsy, or animal autopsy, but were forced to stop due to fears that the body could explode.

"I got blubber, baleen and skin," Stephanie Levesque, strandings officer at IWDG, told the Irish Examiner. "I was going to attempt to get some muscle but I heard some sounds and was like, this is going to explode in my face if I go any deeper." 

Related: $500,000 chunk of 'floating gold' found in dead whale

When whales die, their guts begin to fill with methane gas, which often causes the corpses to inflate like a balloon, float on the ocean's surface — and occasionally float onto shore like the dead fin whale. In high enough concentrations, and when mixed with oxygen in the air, the gas can cause whales to explode, either spontaneously as pressure increases, or when the remains are cut open; although this is very rare, Levesque told Live Science in an email.

In 2013, a marine biologist in the Faroe Islands had a lucky escape after a sperm whale (Physeter macrocephalus) that washed up dead violently exploded when the scientist cut into its stomach, The Guardian reported at the time. And in 2019, an unidentified baleen whale spontaneously exploded on the surface of the sea off the coast of California, spraying blood and guts into the water, according to IFLScience.

Occasionally, wildlife officials will deliberately detonate the gas-filled corpses when they wash up to prevent them from slowly decomposing and releasing foul smells that drive away visitors. The most infamous example of this came in 1970, when a 45-foot-long (14 m) sperm whale that washed ashore in Florence, Oregon, was blown up with half a ton of dynamite, creating an enormous blast that obliterated the remains. 

Related: Weird 'alien' sacks wash up on UK beach, most likely a whale's stomach

With the fin whale in Ireland, it later became clear that the whale was unlikely to explode and it has been left to decompose naturally, Levesque told Live Science. "There was some bubbling [sounds] but nothing that led me to believe it would actually explode." The necropsy was abandoned as a precaution to make sure that the body cavity stayed intact, she added.

Typically, about one to two fin whales wash up in Ireland a year, Levesque told the Irish Examiner. 

There are around 100,000 fin whales worldwide, but the species is still considered vulnerable to extinction due to pressures such as climate change, plastic pollution and overfishing of krill — their preferred food source — by humans, according to the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species.

However, most populations are starting to increase from historic lows caused by the whaling industry in the 19th and 20th century. In January 2022, almost 1,000 individuals — the largest aggregation of the species ever witnessed — were spotted feeding on a giant mass of krill in Antarctica. 

A massive chunk of "floating gold"  has been found in the belly of a dead whale beached on the Spanish island of La Palma. The highly valuable substance — called ambergris — is a waxy material secreted by sperm whales when they swallow indigestible material such as squid beaks. 

Ambergris is used to make perfumes and can sell for thousands of dollars per pound. The chunk found in the Canary Islands weighed about 21 pounds (9.5 kilograms) and could sell for approximately $550,000, according to The Guardian, which first reported the story.

Antonio Fernández Rodríguez, an animal health researcher at the University of Las Palmas, was digging inside the washed-up whale's carcass to try and figure out how it died when he came upon a chunk of something stuck in the whale's intestine, The Guardian reported.

The ambergris seemed to have ruptured the whale's intestine, leading to its death and eventual beaching.

Related: Weird 'alien' sacks wash up on UK beach, most likely a whale's stomach

Only 1% to 5% of sperm whales (Physeter macrocephalus) are found with ambergris — a secretion from the bile duct that is believed to coat indigestible objects the animal has eaten. Normally whales regurgitate these objects, but when they don't, the ambergris helps protect the whale's organs from the sharp material.

This rare substance has been used in perfume-making for hundreds of years because it can help a scent stick to a person's skin — and while synthetic alternatives have since been invented, some companies still use it for certain fragrances.

Sperm whales were one of the most sought-after species in the historical whaling industry, and over-hunting caused their population to plummet. But while the global sperm whale population appears to have stabilized since the decline of whaling in the late 20th century, the species is still considered vulnerable.

Sperm whales are given the highest level of protection under the Convention on International Trade in Endangered Species, an international treaty banning the sale of various threatened species and their parts. But because ambergris is considered an animal waste product, it isn't covered by the treaty and is legal to sell in many countries. (Though not, notably, in the United States, where it is banned from sale and ownership because it is part of a protected animal.)

In the European Union, which includes the Canary Islands, trade of ambergris is legal. Rodríguez told The Guardian he's hoping to sell this newly discovered chunk and use the proceeds to support victims of a 2021 volcanic eruption on La Palmas, which devastated parts of the island, causing an estimated $929 million in damages.

A mysterious, deep-diving whale has died after a "highly unusual" stranding in Gloucester, Massachusetts — and it may have been infected with bird flu, scientists say.

The animal was still breathing when a response crew arrived on the scene at Wingaersheek Beach on May 18. The team had never seen anything like it before.

"It was alive when it initially stranded, and was noted to be somewhat lethargic, but still thrashing occasionally," said Brian Yurasits, a member of the Seacoast Science Center's (SSC) Marine Mammal Rescue team. The long-beaked creature looked like "a mix between a whale and a dolphin," Yurasits told New Hampshire Public Radio (NHPR).

Experts identified the 13.8-foot-long (4.2 meters) animal as a juvenile female Sowerby's beaked whale (Mesoplodon bidens) — one of the "deepest diving animals in the ocean," Yurasits said.

When the tide began to recede, the team decided not to move the whale back into the water due to concerns that it would cause the whale additional harm and distress. The animal was also far from its preferred habitat, which it may have struggled to get back to.

"[Sowerby's beaked whales] spend most of their time off of the continental shelf of the North Atlantic," Yurasits said. "You would never expect to see these things near shore, let alone in a few feet of water."

Related: Mysterious dead beaked whale covered in unusual injuries washes up on California beach 

The whale died a few hours later. Under its stranding agreement with the National Oceanic and Atmospheric Administration (NOAA), the SSC team called scientists at the University of New Hampshire to the scene for a full animal autopsy, known as a necropsy.

The results indicated that the beaked whale had a viral infection that caused its brain to become inflamed and swollen. "The degree of inflammation explains the death of this animal, as well as why it might have been disoriented and strayed into shallow waters," said Inga Sidor, a senior veterinary pathologist at the New Hampshire Veterinary Diagnostic Laboratory and lead veterinary pathologist on the necropsy.

Scientists are still testing the animal's cerebral tissue to determine which virus caused the infection, but "avian influenza is a top consideration," Sidor told Live Science in an email. Only a very small number of cetaceans have been diagnosed with avian influenza, or bird flu, so "it'll be a big deal (at least in the marine mammal world) if it does turn out to be influenza," she added.

The whale's body was otherwise in good condition and showed no signs of injury or trauma.

It is "highly unusual" for a Sowerby's beaked whale to become stranded, SSC staff wrote in a blog post. This recent beaching has given scientists a rare chance to study the enigmatic species, whose lifespan remains a mystery. "Although the loss of an animal like this is unfortunate, we don't often get the opportunity to examine a fresh specimen," Sidor said.

Sowerby's beaked whales can grow up to 21 feet (6.4 m) long and weigh 2,900 pounds (1,300 kilograms), according to NOAA Fisheries. Their range extends from cold, deep waters in the Norwegian Sea to the northeastern coast of Canada and south to the Canary Islands. To feed, these whales dive to depths of around 4,900 feet (1,500 m) and can spend half an hour below the surface.

Closely related species can dive for even longer, such as Cuvier's beaked whale (Ziphius cavirostris), which can hold its breath for over three hours. 

A beluga whale suspected of being an unknowing Russian spy is on the move, possibly in search of love. But it appears that he is headed in completely the wrong direction.

The covert cetacean, known as Hvaldimir, is a male beluga (Delphinapterus leucas) and is believed to be between 13 and 14 years old. Hvaldimir was first spotted in April 2019 in the frigid waters off the coast of Finnmark in northern Norway wearing a harness featuring the words "Equipment of St. Petersburg." The harness was not part of any known beluga whale research project and appeared to have spaces to attach a GoPro camera and other potential spy gear, although nothing was attached at the time. Hvaldimir also displayed no fear of humans, suggesting he had been reared or at least trained by people, which further fueled speculation that he was a spy. Russia has never officially commented on the accusations. (The harness was removed when Hvaldimir was first discovered).

OneWhale, a Norwegian non-profit organization dedicated to protecting Hvaldimir, said that over the last three years, he has spent most of his time in northern Norway. But on May 28, OneWhale spotted Hvladimir near Hunnebostrand, off Sweden's southwestern coast, after rapidly making his way south, French news agency AFP reported. 

"We don't know [exactly] why he has sped up so fast," Sebastian Strand, a marine biologist with the OneWhale organization, told AFP. "It could be hormones driving him to find a mate." However, Hvaldimir's current course is taking him "very quickly away from his natural environment," Strand added.

Related: Lone beluga whale spotted 1,500 miles from home, and nobody knows why

Most male belugas reach sexual maturity by the time they are 15 years old, according to the National Oceanic and Atmospheric Administration (NOAA). So Hvalidimir's hormones could be driving him to search for a mate. 

But the lone whale could also just be looking for other belugas regardless of their gender, Strand said. Belugas are very social creatures, and researchers suspect that Hvaldimir has not come into contact with another member of his own species since they began tracking him in 2019.

Regardless of his motivations, Hvaldimir is traveling in the wrong direction. Beluga whales only live in the high Arctic in areas such as Norway's Svalbard archipelago, Greenland, Canada and Russia. There are no known beluga populations in the waters around Sweden.

Experts aren’t sure why Hvaldimir is going in the wrong direction, but it could be that he was released into Norwegian waters from his Russian home as part of his mission, so he has no knowledge of this part of the world. It is also possible that he spent a prolonged amount of time in captivity, which may have dulled his natural instincts, AFP reported.

So far, Hvaldimir seems to be in good health and has been seen hunting wild salmon near fish farms along Norway's border with Sweden. But previous sightings suggest he may have lost some weight, and experts are concerned that he will struggle to find enough food this far south, AFP reported.

OneWhale is now seeking permission from Swedish authorities to catch Hvaldimir and transport him to a fjord in Norway, which can be turned into a refuge for the whale to spend the rest of his days in peace. A pair of captive belugas from China were successfully released into a similar refuge in Iceland in 2020. (Beluga whales frequently live to around 40 years old but can live up to 70 years, according to NOAA).

This is not the first time Russia has been suspected of training cetaceans for military purposes. In April 2022, satellite images suggested the country had trained dolphins to guard one of its Black Sea bases in Crimea. The U.S. Navy has also trained dolphins and sea lions for military operations since 1959, according to the Naval Information Warfare Center.

Stunning new video shows a pod of orcas attacking two adult gray whales in California's Monterey Bay, in a rare case of predation. Monterey Bay Whale Watch videographer Evan Brodsky, who captured the dramatic footage March 30 using a drone, counted more than 30 orcas. The attacked whales split up and eventually made it to safety in shallower waters after a 6-hour melee, Brodsky wrote in an Instagram post.

The video, which was posted to Facebook April 2, shows the gray whales huddled together as the orcas swoop in from the sides. Monterey Bay Whale Watch said both whales were "badly wounded" during the encounter. 

Orcas (Orcinus orca), also known as killer whales, are the only major predators of gray whales (Eschrichtius robustus), according to the Alaska Department of Fish and Game. But killer whales usually hunt calves rather than adults, opting to "take advantage" of calves that migrate up the coast with their mothers in the first year of their lives, Ari Friedlaender, a marine mammal ecologist at the University of California, Santa Cruz, told Live Science. And even going after a young whale is no easy feat as the pod must still contend with its protective mother. 

That makes the newly filmed attack on the adults unusual.

Related stories: Killer whales spotted for the first time killing blue whales

Still, one attack doesn't necessarily imply a troubling pattern, Friedlaender said. 

"A single event is really something you don't want to raise too big a flag over," Friedlaender explained.

However, if orcas continue to attack adult gray whales, scientists might see the behavior as a sign of an underlying problem, Friedlaender continued. For instance, one potential reason for orcas to continually attack adults is that significantly fewer gray whale calves are available. In that case, the attacks could signify an underlying problem with the gray whale population.

While taking on adults is a big challenge, hunger is also a potent motivator. Friedlaender said the gamble to attack two adults was a matter of "risk-reward," meaning the reward of feasting on more whale meat must be weighed against the higher risk of sustaining injury. At the moment, he said there's not enough information to determine whether the orca population is suffering from food deprivation. Should this trend continue, drone footage showing the whales' size and thickness could be a clue to their wellness. He added that orcas have been known to prey on adult blue, fin and humpback whales, all of which can grow to be bigger than grays.

Orcas can grow up to 32 feet (8 meters) long and weigh over 12,000 pounds (5,400 kilograms), according to National Oceanic and Atmospheric Administration Fisheries. An adult gray whale can reach up to 49 feet (15 m) long and weigh about 90,000 pounds (40,800 kg). Gray whale newborns are around 15 feet (4.6 m) long and weigh 2,000 pounds (900 kg).

Friedlaender said that the whale-watching community will keep an eye out for future oddities. For now, this isolated incident offers an insight into the orcas' hunting prowess and ambition. 

"It never ceases to inspire a lot of awe for the animals," Friedlaender said. "Killer whales are pretty amazing and there's nothing that's too big for them."

A fin whale with a severely deformed spine was recently filmed struggling to swim off the Mediterranean coast of Spain. This extreme case of scoliosis was likely caused by a vessel strike and will probably cause the gentle giant to slowly starve, experts say.

The injured, 56-foot-long (17 meters) fin whale (Balaenoptera physalus) was spotted March 4 by a boat's crew off a beach at Cullera near Valencia. The boat's captain thought the whale was trapped in a fishing net and alerted the Spanish Civil Guard, who sent out a team of biologists and veterinarians from the Oceanographic Valencia aquarium. After arriving on the scene, it became obvious that the whale was not trapped; Instead, it had "scoliosis of unknown origin," according to a Facebook post from Oceanographic Valencia.

The researchers attempted to put a tracking device on the injured animal's back, but it was too deformed for the satellite tag to successfully attach. After "a few hours of attention," the fin whale slowly headed away from the coast and out into deeper waters where it disappeared from view, Oceanographic Valencia representatives wrote. 

Experts told Live Science that the scoliosis was probably caused by a vessel strike that broke the whale's back.

Related: Breaching humpback whale body slams boat in Mexico, injuring everyone on board 

"The term scoliosis simply refers to an abnormal lateral curvature of the spine," Jens Currie, chief scientist of the Pacific Whale Foundation in Hawaii, told Live Science in an email. "The cause of scoliosis can take many forms, but the most common is blunt force trauma." 

It's is likely that the whale "was recently struck by a vessel," Currie said, an opinion shared by Erich Hoyt, a research fellow at Whale and Dolphin Conservation (WDC) in the U.K., and Simone Panigada, president of the Tethys Research Institute in Italy. But the experts also noted that it's hard to know exactly what happened. 

It's possible for large whales to be born with scoliosis or develop it in their early years. But young whales that develop scoliosis almost never live to adulthood, Currie said.

Baleen whales — a group that includes fin whales, blue whales (Balaenoptera musculus), humpback whales (Megaptera novaeangliae) and others — feed by lunging through large shoals of tiny crustaceans known as krill. To do this, they rely on their enormous tails, or flukes, to rapidly propel themselves through the water. But according to the footage, the injured whale is unable to do this, which means it is probably starving. 

"We can see from the video that the whale is already very skinny and beginning to look unhealthy," Currie said. "It is very unlikely it will survive." Baleen whales can survive for many months without properly eating, which means that injuries like this can lead to a "slow and painful death," he added.

Related: Watch footage of 1,000 baleen whales in record-breaking feeding frenzy in Antarctica

This is not the first case of whale scoliosis linked to vessel strikes. In December 2022, a humpback whale called Moon was spotted in Hawaii with a broken back, after swimming more than 3,100 miles (5,000 kilometers) from British Columbia, Canada using only her flippers, according to The Guardian. Last year, Panigada spotted another fin whale with scoliosis near Barcelona, although its spinal deformity was less severe. 

But most whales don’t survive an encounter with a vessel. In total, around 20,000 whales are estimated to be killed by vessel strikes every year, due to a more than 300% increase in global shipping traffic since 1992, according to Friend of the Sea, a non-governmental organization based in Italy. But it's hard to track this because strikes are often unreported and most killed whales will never be found, Hoyt said.

In addition to vessel strikes, whales are also exposed to a lot of noise from shipping that can disrupt their navigation, feeding and communication. "I would say it [ship traffic] is one of the main problems cetaceans face globally," Currie said.

A pair of killer whales has embarked on yet another killing spree, eating the livers of 19 broadnose sevengill sharks (Notorynchus cepedianus) and leaving their carcasses to wash ashore off the coast of Pearly Beach, a village located along the southernmost tip of South Africa.

The baffling carnage caught the attention of Alison Kock, a marine biologist with South African National Parks who tweeted about the "infamous" duo of male orcas (Orcinus orca) known as Port and Starboard and the feeding frenzy that ensued on Feb. 23.

However, this isn't the first time that the orca duo has wreaked havoc in this area. In 2017, the pair slaughtered at least eight great white sharks. And in all but one case they dined solely on the sharks' livers, leaving the rest of their bodies to rot.

So, what is it about shark livers that seemingly whet the appetite of these blood-thirsty orcas? 

Related: Photos: Orcas are chowing down on great-white-shark organs

In her tweet, Kock explained that "they likely initially learn by experience when first predating a new species," meaning that once the orcas were aware of the liver's location on a shark "they will remember it forever and become more efficient [hunters]."

It also helps that shark livers are "highly nutritious and have large quantities of fats and vitamins," Kock told Live Science in an email. "Orcas may have learned that consuming shark livers provides high energy and nutrients. Sharks' livers are large and buoyant, and they float to the surface of the water when a shark is killed. This makes them easy for orcas to spot and access, compared to other organs that may sink to the bottom or be harder to locate."

Similar to tag team wrestling, orcas often hunt in groups or pairs so they can corner sharks. This is important because this gives them an advantage over their prey.

"One orca may distract the shark while another goes in for the kill," Kock said. "This hunting strategy requires high intelligence and social cooperation among the orcas. The orcas may also use their large tails to slap and incapacitate sharks or flip them over to induce tonic immobility. Tonic immobility occurs when a shark is flipped upside down and goes into a trance-like state."

Kock said this kind of behavior has been documented worldwide, including in South America, North America, Australia and New Zealand. However, it wasn't until fairly recently that these attacks were becoming more commonplace amongst sevengill and great whites in South Africa. And the fact that so many sharks died on a single day raises concern.

"This is a large number for a single day of hunting," Kock wrote in her email. "However, the real impact is not on the number of sevengills killed but on how the sharks respond to predation risk by leaving an area, sometimes abandoning aggregation sites. The absence of these top predators (the sharks) could have knock-on impacts on the local ecosystem."

Last year, passengers on board a cruise ship near Antarctica were treated to an extremely rare and spectacular sight: a giant congregation of baleen whales feeding on a gargantuan volume of krill for as far as the eye could see. Although initially estimated at several hundred individuals, the true number of whales in the feeding frenzy may have been closer to 1,000, according to a new study that analyzed footage captured by the lucky whale watchers. 

The incredible spectacle was witnessed Jan. 13, 2022, by guests on board the National Geographic Endurance, a polar exploration cruise ship run by Lindblad Expeditions, which is partnered with National Geographic. The ship was around 9.3 miles (15 kilometers) north of Coronation Island, the largest of the South Orkney Islands, when it came across the feeding frenzy, National Geographic reported. The aggregation mainly comprised fin whales (Balaenoptera physalus), which can grow to around 85 feet (26 meters) long and are second in size only to the blue whale (Balaenoptera musculus).

A video of the massive feeding event, which shows fin whales lunging for food at the surface and filling the air with jets of water ejected from their blowholes, was released on the Lindblad Expeditions-National Geographic YouTube channel on March 8, 2022. 

"We are absolutely surrounded by them," Conor Ryan, a resident zoologist on board the vessel, said in the video. "They are literally bumping into each other because there are so many of them." There were so many whales that you could even smell the whales' breath, which had an odor similar to "rotten broccoli," he added.

Related: Extremely rare gray whale birth captured on camera, possibly for the first time

Ryan initially estimated that there were between 200 and 400 individuals in the aggregation. But it was hard to tell exactly how many there were, because you could see only the whales that were at the surface and not those feeding below, he noted.  

In a new study, published Feb. 20 in the journal Ecology, Ryan and colleagues reanalyzed photos and videos from the event to better estimate how many whales were present. The researchers determined that there were around 970 fin whales in the "supergroup," which makes it the largest aggregation of the species ever recorded. There was also at least one blue whale and a pair of humpback whales (Megaptera novaeangliae) in the area, as well as Antarctic fur seals (Arctocephalus gazella) and thousands of seabirds, including petrels, penguins and albatrosses.

All of the hungry marine animals were feeding on Antarctic krill (Euphausia superba), tiny swimming crustaceans that form massive swarms, as well as the smaller fish that were also feeding on the shrimp-like critters.

This area of the Scotia Sea, which surrounds the South Orkney Islands, is a massive upwelling zone, meaning ocean currents force nutrient-rich waters from the deep to the surface. The feeding event occurred at the end of "a large spring phytoplankton bloom," which provided the necessary food for a rapid explosion in the population of krill, the researchers wrote in the paper.

"There must be millions, if not billions, of tons of krill below us," Ryan said in the video.

Fin whale numbers are on the rise again after historic whaling almost decimated the species in the mid-20th century. There are now around 100,000 individuals worldwide, but they are still considered "vulnerable" to extinction due to pressures such as climate change, plastic pollution and overfishing of krill by humans, according to the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species.

Nevertheless, the sight of such a large group provides hope for conservationists about the species' future.

"A little more than a hundred years ago, seeing something like this probably wouldn't have been that uncommon," study co-author Matthew Savoca, a marine ecologist at Stanford University's Hopkins Marine Station, told National Geographic. This is a sign that we are heading in the right direction, he added.