Mysterious skull of ancient whale

According to the results of fossil skeleton research of an ancient whale, scientists have come to the conclusion that the whale's skull is originally spiral.

They explain, with this distorted skull structure, that whales can adapt to aquatic habitats, making them better able to hear.

The discovery adds new features, interesting, and mysterious things about the evolutionary process, adapting to the habitat of the largest animal that once lived on Earth.

The Whale contains about 90 species, almost all of which are ocean animals, except for 5 freshwater dolphins. The surviving species in this set are divided into 2 sub-groups of toothed whales (sperm whales) , which perform the positioning by echoes and baleen whales . This whale has horns in its jaws (instead of teeth), which are used to filter food from seawater but have little need for echolocation and have symmetrical skulls.

Picture 1 of Mysterious skull of ancient whale
Whales play 'against' the sea

Scientists have argued that archaeocetes , one of the original whales, also known as Basilosaurus , evolved from terrestrial mammals and later evolved into two modern whales today that have skulls. symmetrical similar to mammals. One hypothesis is that toothed whales have evolved with twisted skulls to match the echolocation. These coils help them hear more clearly underwater.

However, the researchers found that the history of whale evolution is a complex story, not as simple as we thought when constructing the skull of archaeocetes, one of the ancient whales. Great re-asymmetry. This is in stark contrast to previous studies.

"This shows that the asymmetry has existed for a long time compared to previous thoughts, even before the whale period was divided into two main groups: the horned whale and the toothed whale. " , researcher Julia Fahlke, a paleontologist from Ann Arbor University, Michigan, USA.

The brain is deformed

Fahlke started the study with the help of another expert, Philip Gingerich, from the University of Michigan Paleontology Museum to learn about the evolutionary processes of these 'aquatic monsters' . . Thereby will provide more for her research on the structure and change of evolution of this species over time is like.

Fahlke started his work by studying Basilosaurus, a species of whale that lived 40 to 34 million years ago in the late Eocene that has a long body like a reptile. It is one of the 10 most frightening sea creatures.

"We had a 3-D model of the skull created from a 3-dimensional CT scan, and found that it was" deformed , " Fahlke said in the US LiveScience Science journal. "Like everyone, we think this may have happened in the process of burial and fossil."

"Maybe the skull of this ancient whale is not symmetrical ," she said. However, it also takes time to confirm this information before making an official conclusion.

Picture 2 of Mysterious skull of ancient whale
Whales always contain interesting things for scientists (Source: Livescience.com)

A mysterious story

To pursue this research, Ms. Fahlke conducted a follow-up of the archaeocete's skull, currently on display at the University of Michigan Paleontology Museum. It is home to the world's largest and most complete fossil collection of extinct whales.

The researchers analyzed this asymmetry by comparing the six skulls of different ancient whales. The results showed no signs of artificial distortion. Next, the team measured skulls deviating from a straight line.

In general, six archaeocete skulls are all symmetrical in shape. And two of the six skulls don't have symmetry.

These findings suggest that the asymmetry in whale skull construction has not evolved with the development of echolocation. However, the researchers believe that the spiral is capable of connecting to sound, helping whales improve their hearing.

The finding also suggests that the baleen whales, one of the largest animals that ever lived, the blue whales initially had distorted skulls, which later came straight out.

"It is very interesting to study the horned whale's skull to see if it is symmetrical, and when evolution is symmetrical, is it altered," she said.

Fahlke, Gingerich, Wood and their colleagues, Robert Welsh, described this study in detail in the Science Journal of the National Academy of Sciences on August 22.