Infernogallus jamesi Shows 15-Millimeter Sliding Jaw Adapted to Mash Fruit

3 articles · Updated · The Brighter Side of News · Oct 28

Nature Communications researchers described Infernogallus jamesi, a 12-kilogram, turkey-sized caenagnathid whose nearly complete skull points to a diet of soft plants, with fruit likely among its foods.
CT scans and digital reconstructions showed a toothless lower jaw that could slide forward and backward by as much as 15 millimeters, while ridged mouth surfaces and muscle orientation favored mashing over a strong vertical bite.
Comparisons across 19 dinosaur and bird species found the closest functional match in the fruit-eating vulturine parrot, though the authors said the fossil does not prove an exclusively fruit-based diet or seed dispersal.
The five known specimens come from the latest Cretaceous Hell Creek Formation and nearby sites, adding a small specialist to a fauna better known for giants such as T. rex and Triceratops.
The study argues that such feeding adaptations may have tracked the Cretaceous spread of flowering-plant fruits, suggesting dinosaur diets were more specialized than isolated bones had indicated.