The Tyrannosauridae family, colossal carnivorous dinosaurs reigning over terrestrial ecosystems around 80-66 million years ago during the Late Cretaceous Period, underwent substantial physical transformations throughout their growth stages.
They transitioned from agile and slender forms to more robust and stout shapes, indicating an adaptation to higher ecological niches that coincided with changes in their prey. While it’s established that adult tyrannosaurs hunted large herbivorous dinosaurs like Triceratops, the dietary habits of juvenile tyrannosaurs have remained a mystery.
In a groundbreaking revelation, scientists unearthed an almost complete skeleton of a juvenile Gorgosaurus, a species within the Tyrannosauridae, retaining remarkably well-preserved stomach contents in its abdominal cavity.
This find shed light on the feeding preferences of young tyrannosaurs. The stomach contents unveiled the hind limbs and remnants of two small juvenile dinosaurs, recognized as Cytipes. Intriguingly, the two Cytipes were preyed upon at different intervals, evident from their placement in the abdominal cavity and varying degrees of digestion.
This discovery implies that juvenile Tyrannosauridae favored preying on smaller dinosaurs, a dietary divergence from the adults that predominantly targeted large herbivorous dinosaurs.
Consequently, these revelations reinforce the theory that the diet and ecological roles of Tyrannosauridae shifted as they matured, offering invaluable insights into the life cycle of these captivating creatures.
Header Image Credit : University of Tsukuba