Paleontologists have identified a new dinosaur species, Infernogallus jamesi, nicknamed the "Hell Chicken," that is the first known dinosaur to have subsisted solely on fruit. The discovery, detailed in the journal Nature, challenges previous assumptions about dinosaur diets and highlights their diverse ecological roles.
Residing approximately 66 million years ago during the Cretaceous period, Infernogallus jamesi lived in what is now the Hell Creek Formation, spanning parts of Montana, North Dakota, South Dakota, and Wyoming. This region was then a subtropical coastal plain inhabited by well-known dinosaurs such as Triceratops and Tyrannosaurus Rex. Despite belonging to the theropod group, which includes carnivorous dinosaurs like T. Rex, the "Hell Chicken" possessed specialized adaptations for a frugivorous diet.
The five-foot-tall, 25-pound dinosaur exhibited unique mouthparts, including jaw muscles capable of chewing motions and ridges on its beak designed to snip and mash fruit. These features are similar to those found in modern turtles and parrots, but have never before been observed in a single dinosaur species. Researchers suggest these adaptations were crucial for processing fruits and separating seeds from flesh.
"It's pretty rare for animals to become specialized for a diet of fruit, so when it happens, it comes with some remarkable adaptations," said Dr. Thomas Dudgeon of the Royal Ontario Museum, a co-author of the study. The specific fruits consumed by Infernogallus jamesi remain unknown, but potential candidates include berries and drupes.
The discovery sheds light on the evolving relationship between dinosaurs and flowering plants, which emerged earlier in the Cretaceous period. As fruits became more prevalent, dinosaurs like Infernogallus jamesi evolved to exploit this food source. This dietary specialization also indicates dinosaurs may have played a significant role in seed dispersal, contributing to the evolution and spread of flowering plants, a niche now occupied by modern reptiles, small mammals, and birds.
"This definitely expands the range of lifestyles we thought dinosaurs had, and it shows how adaptable theropods were," noted Dr. Gregory Funston, an assistant professor at Stony Brook University and study co-author. Like many theropods, the "Hell Chicken" likely possessed feathers, further diversifying the known characteristics of this group of dinosaurs.