The story of evolution takes place over the course of millions of years, and it is often so wild that nobody could come up with it on their own. One of the most interesting things that has occurred was that long ago, sea creatures walked, swam, or slithered out of the oceans and evolved to become land animals.

This would occur over the course of many generations where an animal that was once lived its entire life in the water would develop the ability to come out of the water for a period of time, then it evolved to spend more time out of the water, and eventually became entirely terrestrial.

All the land animals can trace their beginning back to this type of event since life began in the oceans.

One the animals were on land, they expanded and specialized to become thousands of different species. Eventually, however, some of those species started going back into the water.

This was undoubtedly just to hunt, avoid predators, cool down, or maybe even for fun at first. Once again, over the course of generations, they began spending more and more time in the oceans until eventually, they were marine animals.

This raises the question about how and when this happened. Of course, since these things happened in the distant past, it can be hard to figure out. A team of researchers, however, looked at the details of hundreds of different museum specimens. They took over 11,000 new measurements, added photos, and even took CT scans.

All of this data was fed into system that could study them in greater detail than was possible before. Bhart-Anjan Bhullar is an associate professor of Earth and planetary sciences in Yale’s Faculty of Arts and Science. He is also the associate curator of vertebrate paleontology and vertebrate zoology at the Peabody Museum, and the senior author of this new study, which was published in Current Biology. In a statement about the study, he said:

“Reconstructing the lives of extinct life forms in a scientifically rigorous way, as opposed to just telling stories, is a precise and delicate undertaking. It requires a careful interweaving of data from modern organisms, of which our understanding is necessarily far deeper, and knowledge of these living organisms’ genealogy relative to fossil forms.”

The team had to overcome many challenges in interpreting the data. For example, some species of animals have clear aquatic adaptations on their limbs, but others are more ambiguous. This could indicate that they were once terrestrial, or their aquatic adaptations took an unusual turn. In the statement, Caleb Gordon, the lead author and a postdoctoral researcher at the Florida Museum of Natural History, said:

“In these cases, paleontologists are often stuck, as different lines of evidence disagree about what the ancient animal was like.”

In their research, the team was able to find that the best way to determine the animal’s history with the water was through hand length measurements, which they determined to be around 90% accurate.

Understanding the historical journey that these animals took gives a more complete picture of how various animals evolved. This is not only interesting for understanding the environment better, but also for looking forward at how animals will continue to adapt to an ever changing world.

If you thought that was interesting, you might like to read about a second giant hole has opened up on the sun’s surface. Here’s what it means.