WASHINGTON: Paleontologists have found a well-preserved fossil of a four-legged amphibious ancestor of whales, a discovery that sheds new light on the mammals’ transition from land to the ocean.
The ancestors of whales and dolphins walked on Earth about 50 million years ago in the regions that now comprise India and Pakistan.
Paleontologists have previously found partial fossils of the species in North America that were 41.2 million years old suggesting that by this time, the cetaceans had lost the ability to carry their own weight and walk the Earth.
The new specimen, described in a study published Thursday in the journal Current Biology, is 42.6 million years old and provides fresh information on the evolution of cetaceans.
The fossil was found about 0.6 miles (one kilometer) inland from Peru’s Pacific coast, at Playa Media Luna.
Its mandibles grazed the desert soil and during excavations, the researchers found the lower jaw, teeth, vertebrae, ribs, parts of front and back legs, and even the whale ancestor’s long fingers that were likely webbed.
Based on its anatomy, the scientists say this cetacean of about 13 feet (four meters) long could both walk and swim.
“Part of the tail’s vertebrae showed similarities with that of present-day semi-aquatic mammals like otters,” lead author Olivier Lambert of the Royal Belgian Institute of Natural Sciences told AFP.
“This would therefore have been an animal that would have started to make growing use of its tail to swim, which differentiates it from older cetaceans in India and Pakistan.”
Pieces of four-legged whales were found in Egypt, Nigeria, Togo, Senegal and Western Sahara, but they were so fragmented that it was impossible to decisively conclude whether they could swim.
“This is the most complete specimen ever found for a four-legged whale outside of India and Pakistan,” said Lambert.
If the whale in Peru could swim like an otter, the researchers hypothesized that it likely crossed the Atlantic from the western coast of Africa to South America. As a result of continental drift, the distance was half that of today, around 800 miles, and the east-west current of the time would have facilitated their travel.
This finding would make less likely another hypothesis according to which whales reached North America via Greenland.
The Pisco Basin, off Peru’s southern coast, likely holds numerous fossils, given its excellent conditions for preservation.
“We have work for at least the next 50 years,” said Lambert, the paleontologist.
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Four-legged prehistoric whale fossil found in Peru
Four-legged prehistoric whale fossil found in Peru
- The new specimen, described in a study published Thursday in the journal Current Biology, is 42.6 million years old and provides fresh information on the evolution of cetaceans
Viral phenomenon in Argentina has young people identifying themselves as animals
BUENOS AIRES: On a recent Sunday, a Buenos Aires plaza transformed into a makeshift wilderness for an unusual group of teenagers.
Sofía, wearing a lifelike beagle mask, ran across the grass on all fours. Nearby, 15-year-old Aguara leapt through the air, clearing an obstacle course while imitating the precise movements of a Belgian breed dog. Others dressed as cats and foxes perched in the branches of trees, keeping their distance from curious onlookers.
It was the latest gathering of “therians,” individuals who say they identify mentally, spiritually or psychologically with non-human animals. The trend has taken over Argentine social media over the past few months, gaining traction on platforms like TikTok, where the hashtag #therian has surpassed 2 million posts, with Argentina leading all other Latin American countries in engagement. The surge has drawn the attention of influencers and media outlets alike, sparking reactions that range from laughter and bewilderment to outright anger.
And as the movement gains traction, psychologists are stepping in to analyze the phenomenon and its place in public discourse.
Aguara, who claims to identify as a Belgian Malinois and counts her age as the equivalent of two years and two months in dog years, says she’s a lot like any other teenager.
“I wake up like a normal person and live my life like a normal person,” she said. “I simply have moments when I like being a dog.”
As the leader of what she calls her “pack,” Aguara — the name she identifies with — boasts more than 125,000 followers on TikTok and coordinates regular meetups around the Argentine capital.
Aru, a 16-year-old who wore a seal mask to the park meetup, said she considers herself part of the “otherpaw” branch of therians: individuals who wear masks and tails or move on all fours just for fun. “It’s not necessarily about identifying as an animal,” she said.
She reckons the therian trend took off in Argentina because of the country’s “fairly free” environment. For other young Argentines, the movement has provided a vital community where they can feel truly accepted.
Should parents be worried?
Débora Pedace, a psychologist and director of the Integral Therapeutic Center in Buenos Aires, acknowledged that the phenomenon generates a complex mix of confusion, laughter and even anger.
“From a psychological standpoint, this is a symbolic identification with an animal,” Pedace said. “It becomes pathological or alarming only when it turns into a deeply rooted belief and the person fully assumes the role of an animal, potentially leading to self-harm or hurting others.”
Sofía, wearing a lifelike beagle mask, ran across the grass on all fours. Nearby, 15-year-old Aguara leapt through the air, clearing an obstacle course while imitating the precise movements of a Belgian breed dog. Others dressed as cats and foxes perched in the branches of trees, keeping their distance from curious onlookers.
It was the latest gathering of “therians,” individuals who say they identify mentally, spiritually or psychologically with non-human animals. The trend has taken over Argentine social media over the past few months, gaining traction on platforms like TikTok, where the hashtag #therian has surpassed 2 million posts, with Argentina leading all other Latin American countries in engagement. The surge has drawn the attention of influencers and media outlets alike, sparking reactions that range from laughter and bewilderment to outright anger.
And as the movement gains traction, psychologists are stepping in to analyze the phenomenon and its place in public discourse.
Aguara, who claims to identify as a Belgian Malinois and counts her age as the equivalent of two years and two months in dog years, says she’s a lot like any other teenager.
“I wake up like a normal person and live my life like a normal person,” she said. “I simply have moments when I like being a dog.”
As the leader of what she calls her “pack,” Aguara — the name she identifies with — boasts more than 125,000 followers on TikTok and coordinates regular meetups around the Argentine capital.
Aru, a 16-year-old who wore a seal mask to the park meetup, said she considers herself part of the “otherpaw” branch of therians: individuals who wear masks and tails or move on all fours just for fun. “It’s not necessarily about identifying as an animal,” she said.
She reckons the therian trend took off in Argentina because of the country’s “fairly free” environment. For other young Argentines, the movement has provided a vital community where they can feel truly accepted.
Should parents be worried?
Débora Pedace, a psychologist and director of the Integral Therapeutic Center in Buenos Aires, acknowledged that the phenomenon generates a complex mix of confusion, laughter and even anger.
“From a psychological standpoint, this is a symbolic identification with an animal,” Pedace said. “It becomes pathological or alarming only when it turns into a deeply rooted belief and the person fully assumes the role of an animal, potentially leading to self-harm or hurting others.”
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