Along The Coast of Peru, Ancient, Four-Legged Whale Are Found

The presence of small hooves at the tip of the whale's fingers and toes and its hip and limbs morphology all suggest that this whale could walk on land, according to the researchers. On the other hand, they say, anatomical features of the tail and feet, including long, likely webbed appendages, similar to an otter, indicate that it was a good swimmer too.

Olivier Lambert, from the Royal Belgian Institute of Natural Sciences said that for the very first time, a quadrupedal whale skeleton was found in the whole Pacific Ocean, which is the oldest for the Americas and definitely outside of India and Pakistan.

A few years ago, an unexplored new area was discovered for digging fossils in the coastal desert of southern Peru, named Playa Media Luna. This was founded by Mario Urbina – study co-author from Museo de Historia Natural-UNMSM, Peru. In a field expedition organized by an International team that included members from different countries like Peru, France, Italy, the Netherlands, and Belgium in the year 2011, the team unearthed the remains of an ancient whale, that was named as Peregocetus pacificus, by the team. The meaning of this term is - the traveling whale that reached the Pacific.

Lambert further adds that while digging the nearby areas of the outcropping bones, the team understood the fact that this skeleton belonged to a  quadrupedal whale, that had both forelimbs and hind limbs.

With the help of microfossils, the sediment layers where the skeleton was positioned were precisely dated to the middle Eocene, 42.6 million years ago. Anatomical details of the skeleton allowed them to infer that the animal was capable of maneuvering its large body (up to 4 meters long, tail included), both on land and in the water. For instance, features of the caudal vertebrae (in the tail) are reminiscent of those of beavers and otters, suggesting a significant contribution of the tail during swimming.

The researchers report suggests that early cetaceans reached the New World across the South Atlantic, from the western coast of Africa to South America. This hypothesis strongly backs the geological age of the new four-limbed whale and its presence along the western coast of South America.

The whales would have been assisted in their travel by westward surface currents and by the fact that, at the time, the distance between the two continents was half what it is today. The researchers suggest that, only after having reached South America, the amphibious whales migrated northward, finally reaching North America.

The international team continues to study the remains of other whales and dolphins from Peru. Concluding the discussion, Lambert says that the team will continue to march forward and will search in localities that have layers which are extremely ancient, even more than the Playa Media Luna. They are hopeful that older older amphibious cetaceans might get discovered in the near future.

By: Preeti Narula

Content: https://www.sciencedaily.com/releases/2019/04/190404114455.htm