Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

Summary

A first-of-its-kind study traces the rise of ant- and termite-eaters, revealing how mammals returned to the evolutionary table — at least a dozen times — to hone traits for feasting on the social insect bonanza that exploded after the extinction of the dinosaurs. Mammals have developed some unusual eating habits over the past 100 million years, but a new study has uncovered the surprising lengths some have gone to satisfy one of the more peculiar — a taste for ants and termites. Findings published in Evolution reveal that mammals independently evolved specialized adaptations for exclusively feeding on ants and termites at least 12 times since the Cenozoic era began, roughly 66 million years ago. Researchers say the convergent evolution among mammals toward this dietary strategy — called myrmecophagy — emerged following the K-Pg extinction and fall of non-avian dinosaurs, which reshaped ecosystems and set the stage for ant and termite colonies to rapidly expand worldwide, driving extreme shifts in feeding modes for certain species. “There’s not been an investigation into how this dramatic diet evolved across all known mammal species until now,” said Phillip Barden, the study’s corresponding author and associate professor of biology at New Jersey Institute of Technology (NJIT). “This work gives us the first real roadmap, and what really stands out is just how powerful a selective force ants and termites have been over the last 50 million years — shaping environments and literally changing the face of entire species.” Over 200 mammal species are known to eat ants and termites today, yet only about 20 true myrmecophages — such asgiant anteaters, aardvarks and pangolins — have evolved traits like long sticky tongues, specialized claws and stomachs, and reduced or missing teeth, to efficiently consume thousands of these insects daily as their sole food source. To understand how often and when mammals evolved such traits, the team compiled dietary data for 4,099 mammal spe...