Fossil of a whale species weighing 340 t found in Peru – 03/08/2023 – Science

About 20 meters long and weighing up to 340 tons (surpassing the body mass of even the largest dinosaurs), a species of whale that inhabited the region where Peru is today may have been the heaviest animal ever recorded. on planet Earth.

In an article published in the latest edition of the journal Nature, a team of scientists presents the animal, baptized, due to its geographic origin and its colossal dimensions, as Perucetus colossus.

The remains were found in Peru, in the Ocucaje desert, which is home to a series of fossil treasures from the ancient Peruvian sea. When they came across the remains of the whale, scientists came to think that they were rocks, due to the unusual hardness of the material.

The discovery was actually a set of gigantic bones from “an animal that we didn’t think could exist”, reports Aldo Benites-Palomino, a researcher at the University of Zurich and one of the authors of the work.

The paleontologist made a series of publications on social networks to provide details and present the backstage of the research. “We excavated the remains of this animal in a huge job of extracting vertebrae that weigh more than 180 kilos,” he revealed.

Scientists were able to recover a partial skeleton, including 13 vertebrae, 4 ribs and 1 hip bone, all of which were large.

When they began to analyze the material, the scientists were surprised by the density and compactness of the bones identified, and then proceeded to a detailed analysis of the composition.

The next step was the construction of a 3D model of the ancient whale, which made it possible to estimate the anatomical details of the species more clearly and compare it to other animals.

The results of the simulations revealed the expressive dimensions of the Peruvian species, indicating that the animal’s mass would be at least 85 tons. The estimated maximum weight, in turn, was 340 tons.

The result, according to the work, “potentially represents the heaviest animal ever described”.
Currently, the title of heaviest animal in the world belongs to the blue whale (Balaenoptera musculus), whose largest specimens reach around 190 tons.

“Discoveries of such extreme body shapes are an opportunity to re-evaluate our understanding of animal evolution. It seems that we are only vaguely aware of just how amazing whale shapes can be”, evaluate JGM Thewissen and David A. Waugh, two specialists in the subject. to the Medical University of Northeast Ohio.

The duo, who did not participate in the research, published an article analyzing the discovery, also in the journal Nature.

Due to the absence of important parts of the fossil, such as the skull and teeth, there are still many doubts about the percetus colossus. Scientists already know, however, that it lived in shallow waters and moved slowly.

Unlike most whales, though, the new species was probably not an active predator. One of the hypotheses for the animal’s diet is that it was a type of scavenger, feeding on the carcass of sunken vertebrates.

In addition to a possible new heavyweight in the animal world, the work also contributes to understanding the evolution of cetaceans — a suborder of mammals that includes dolphins, whales and porpoises.

The discovery of percetus colossus and the conclusions presented by the group indicate that the trend towards gigantism in cetaceans may have happened around 30 million years earlier than indicated by previous studies.

For all this, although they highlight the limitations of the work and the many gaps that still exist about the life and behavior of the Peruvian whale, the analysis published by Thewissen and Waugh says that it can mean more than just a new species for science.

“It is too early to say, but such considerations demonstrate that the importance of this fossil goes beyond documenting a hitherto unknown form of life,” they write.