Research explains why jars have changed so little since the age of dinosaurs

New research by scientists at Bristol University explains how an evolutionary pattern could be ‘stopped’, governed by environmental change, explaining why crocodiles have changed so little since the age of dinosaurs.

Crocodiles today look very similar to those from the Jurassic period about 200 million years ago. Very few species survive today – only 25. Other animals such as berries and birds have achieved a diversity of thousands of species in the same period or less.

Prehistory also saw pottery that we do not see today, including giants as big as dinosaurs, plant eaters, fast runners and serpentine creatures that lived in the sea.

In the new research, published today in the journal Nature Communication Biology, the scientists explain how jars follow an evolutionary pattern called ‘punctuated equilibrium’.

Their rate of evolution is generally slow, but sometimes they accelerate as the environment has changed. In particular, this new research suggests that their evolution goes faster when the weather is warmer, and that their body size increases.

Lead author Dr Max Stockdale from Bristol University’s School of Geography Sciences said: “Our analysis used a machine learning algorithm to estimate evolution rates. The rate of evolution is the rate of change that has occurred over time. specific, which we can work out by comparing measurements from fossils and taking into account age.

“For our study we measured body size, which is important because it interacts with how fast animals grow, what food they need, how big they are. numbers and their likelihood of extinction. “

The results show that the limited diversity of crocodiles and the lack of evolution seem to be due to a slow rate of evolution. The crocodiles seem to have come up with a body plan that was very efficient and flexible enough that they would not have to change in order to survive.

This flexibility could be one explanation for why pottery survived the meteor effect at the end of the Cretaceous period, in which the dinosaurs disappeared. Crocodiles usually thrive better in warm weather because they cannot control their body temperature and need warmth from the environment.

The climate at the age of dinosaurs was warmer than it is today, which may explain why there were so many more crocodile species than we see now. Being able to draw energy from the sun means they don’t have to eat as much as a warm-blooded animal like a bird or mammal.

Dr Stockdale said: “It’s interesting to see the close relationship between the earth and the living things we share with it. The pots have come up with a way of life that is flexible enough to accommodate change. environmental strikes that have occurred since dinosaurs were around. “

The next step for the team’s research is to find out why some types of prehistoric crocodile became extinct, but others did not.

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