Why did T. rex have such tiny arms? Scientists now think it’s because its giant head became the ultimate hunting tool. Across ...

The newly described mosasaur Tylosaurus rex spanned up to 43 feet (13 meters) long and may have been one of the fiercest ...

A new study explores the reason why the dinosaur T. rex has tiny arms.

It ran on the tips of its toes. Its bite was brutal enough to take down a titan. And its neck was so strong, there was no way ...

The evolution of tiny arms in several groups of meat-eating dinosaurs was likely driven by the development of strong, ...

Five different groups of predatory dinosaurs independently evolved disproportionately small arms, and it seems they did so because their heads became so large and powerful ...

Scientists have long puzzled over the origins of a mysterious dinosaur excavated in the 1940s: Was it a young T. rex or another type of dinosaur? At first, researchers had only a tyrannosaur skull to ...