Question Corner: Why haven’t crocodiles evolved much since the age of the dinosaurs?
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The crocodiles of today look very similar to those that lived during the Jurassic period some 200 million years ago. Though lizards and birds have evolved and diversified into many thousands of species, crocodiles have only a few species – just 25.
Now, scientists at the University of Bristol explain how a particular pattern of evolution known as the ‘stop–start’ pattern and certain environmental changes could explain why crocodiles haven’t changed much.
In a paper published in the journal Communications Biology, the scientists explain that crocodiles have a very slow rate of evolution. The team used a machine-learning algorithm to estimate the rates of evolution.
Lead author Max Stockdale from the University of Bristol’s School of Geographical Sciences said in a release that it was fascinating to see how intricate a relationship exists between the Earth and the living things we share it with. He explains that the crocodiles landed upon a lifestyle that was versatile enough to adapt to the enormous environmental changes that have taken place since the dinosaurs were around. The team is also working to identify why some types of prehistoric crocodiles died out, while others didn’t