Evolution was a snap behind the success of an old crocodile

New research led by the University of Bristol has revealed that pottery once flourished on land and in the oceans as a result of rapid evolution.

Today’s crocodiles are predators that live in rivers, lakes and wetlands, catching fish, reptiles, birds and mammals with their prominent jaws and powerful jaws.

However, new research was published today in the journal Proceedings of the Royal Society B., showing that ancient crocodiles were far more diverse due to rapid evolution.

In the time of the dinosaurs, some crocodiles were experimenting with dolphin-like adaptations to live in the oceans, while others lived on land as eaters of fast-moving plants. .

The researchers studied more than 200 skulls and jaws, including fossils from the entire history of a 230-million-year-old crocodile and their extinct relatives. They studied shape differences to reveal differences between species and analyzed how quickly crocodile groups changed over time.

It turns out that some extinct crocodile groups, including dolphin-like thalattosuchians and small-landed notosuchians, grew rapidly over many millions of years, and became to major changes in their skulls and jaws as they expanded into areas that were present in another animal. groups, especially mammals.

The research also shows that crocodiles, crocodiles and garials, the only living crocodiles, are more conservative than the extinct fossil groups, which have gradually evolved over the last 80 million years. , but there is no evidence that they are slowing down and are not ‘living fossils’, as was once thought.

Lead author Dr Tom Stubbs, Senior Research Associate at Bristol University’s School of Earth Sciences, said: “Crocodiles and their ancestors are an amazing group for understanding the rise and fall of biodiversity.

“There are only 26 crocodile species around today, and most of them look very similar. However, there are hundreds of fossil species with a remarkable difference, especially in their feeding equipment.”

Dr Armin Elsler, Research Associate at Bristol School of Earth Sciences and co-author, said: “New state methods now mean we can test for differences in the rate of evolution over time and across organizations. “

It has long been said that dramatic changes in habitat and diet can stimulate rapid evolution, but these patterns are usually only reported in highly mixed groups today, such as birds, mammals and mammals. fish. This is the first time this trend has been demonstrated in pottery, a group with a rich fossil history, but low modern diversity.

Dr Stephanie Pierce, Associate Professor of Organic Biology and Evolution at Harvard University, said: “Ancient pottery came in a variety of forms. They were transformed into running on land, swimming in the sea. water, carving fish, and even chewing plants.

“Our study shows that these very different lifestyles developed very quickly, allowing crocodiles to become extinct quickly and to gain control of novel ecological areas. over many millions of years. “

Professor Michael Benton from Bristol said: “It is not clear why today’s crockery is so limited in their adaptations. If we only had the living species, we could say that they are limited in the methods their lives by being cold with blood or because of their anatomy.

“However, the fossil record shows their remarkable capabilities, including large numbers of species in the oceans and on land. They may have only done well when the global climate was more warmer than today. ”

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