Cat-Sized T. rex Babies Were Quick to Hunt, Study Finds

A Biology (2026) study of tyrannosaurid hatchlings, including T. rex and Gorgosaurus libratus, shows newborns weighed about 2.5 kg (cat-sized) but grew rapidly, with vascularized bones and tooth wear suggesting early hunting. CT scans indicate these young dinosaurs left the nest quickly, likely hunted soon after hatching, and the brood may have comprised 20–30 eggs, implying a strategy of many small young with relatively light parental investment.