Since the discovery and classification of Tyrannosaurus remains, scientists have been troubled by the question: why are very similar but very small carcasses found around the world from time to time? Are they Tyrannosaurus cubs or a separate species of ancient reptile? A new study by scientists from the University of Bath and the University of Chicago points to the second option.
The creatures were named Nanotyrannus lancensis, an example of scientific humor. “Nanotyrannosaurs” were up to 5 meters long and weighed 1500 kg, but that’s only 15% of the size of an adult Tyrannosaurus, so they really did look small. About 150 differences in the bones of these two species have been found, revealing their main difference. Nanotyrannosaurs had long, tenacious, functional forelimbs, rather than rudimentary offshoots like the larger Tyrannosaurs.