Tyrannosaurus rex has a reputation for being one of the biggest and fiercest dinosaurs ever to have lived. But it probably wasn’t the brightest: it had a simpler brain than an earlier, smaller tyrannosaur. The change could be a consequence of growing so large.
Fossils suggest that T. rexcould reach 12 metres in length and between 8 and 14 tonnes in weight. It belonged to a family of dinosaurs called the tyrannosaurs – but not all of them were large, for instance, the Dilong paradoxus which was 1.6 m (5ft 2 inches) in length. However, this specimen was a juvenile and would have become 2 m (6 feet) fully grown.
Now, the solution that New Scientist has for this dinosaur, is that it “dumbed down” its brain.
Did not know that dinosaurs had that faculty.
Ye, Yvaine. 2018. T. rex evolved into a monster predator by dumbing down its brain. New Scientist (3 October).