One of the most enduring tropes about crocodiles is to describe them as “living fossils”. They are cold, slow-moving and scaly, so they look like how one might picture a dinosaur. Like many clichés, there is an element of truth to this comparison. The crocodiles from 200 million years ago look surprisingly like the ones we know today.
But why have the modern crocodilians, including crocodiles, alligators and caimans, changed so little over such an immense span of time? In new research, we have attempted to answer this question using advanced evolutionary modelling.
Relatives of crocodiles have been around for an extraordinary length of time, their fossil remains having been found in rocks from the early Jurassic period, around 200 million years old. Stranger still, these crocodiles from the age of the dinosaurs often look surprisingly like the crocodilians of today. All modern forms have long snouts, powerful tails, armoured skins and a sprawling gait, and many fossil…