Scientists Keegan Melstom and Randall Irmis at the National Museum of Utah at the University of Utah have found multiple ancient groups of crocodyliforms – the group including living and extinct relatives of crocodiles and alligators – were not the carnivores we know today. Evidence suggests that a veggie diet arose in the distant cousins of modern crocodylians at least 3 times.
Through studies of the complexly shaped teeth showed that extinct crocodylians ate plants at least three times and maybe as many as six. All living crocodylians posses a similar general body shape and ecology to match their lifestyles as semiaquatic generalist carnivores, which includes relatively simple, conical teeth. However, the extinct species showed a different pattern.
The extinct species showed much more complex teeth – which suggests that they are plant eating crocodiles. To infer what those extinct crocodyliforms most likely ate, Melstrom and his graduate advisor, chief curator Randall Irnis, compared the tooth complexity of extinct crocodyliforms to those of living animals using a method originally developed for use in living mammals. Overall, they measured 146 teeth from 16 different species of extinct crocodyliforms.
Results show that these animals had a wider range of dental complexities and presumed dietary ecologies than had been appreciated previously. This study demonstrates that extinct crocodyliforms had an incredibly varied diet. Some were like living crocodylians and where primarily carnivorous while others were omnivores and still others likely specialised in plants. The herbivores lived on different continents at different times, some alongside mammals and mammal relatives, while others did not.
The research helps in understanding of the extinct relatives of crocodiles and more studies will be conducted to further understand why the crocodiles were diversified so radically after one mass extinction but not another, and if dietary ecology could have played any role.
Source material from Science Daily