Study examines how developmental changes modified the reptiles’ snouts
The story that’s often told about crocodiles is that they’re among the most perfectly adapted creatures on the planet — living fossils that have remained virtually unchanged for millions of years. The reality is far more interesting. Throughout their evolutionary history, crocodiles, alligators, and their kin have repeatedly evolved similar skull shapes in response to dietary specializations: long snouts for eating fish; short snouts for harder prey; and moderate snouts for large prey. But how is such broadscale convergence generated? Research led by Stephanie Pierce, associate professor of Organismic and Evolutionary Biology, and Zachary Morris, Ph.D. ’20, aims to tackle this question by comparing embryonic development with later growth in all species of living crocodiles. Their work demonstrates that the diversity of skull shapes found today was realized by altering developmental patterns during evolution. The study is described in a Feb. 20 paper published in the Proceedings of the Royal Society B. The work...