I’m on the road in Japan having just made it to Katsuyama, home of the famous Fukui Prefectural Dinosaur Museum. That I’ll get to see tomorrow and in due course posts will follow, but in the mean time you will have to be satisfied by this very quick post. The title is hardly spectacular – I’m not sure anyone with even a passing knowledge and interest in dinosaurs is not aware of the fact that the giant tyrannosaurs like Tyrannosaurus had proportionally small arms. However, this photo is a really good illustration of just how small some of them were.
The humerus (upper arm bone) in question is a genuine one of a Tarbosaurus (basically the asian Tyrannosaurus and very simiular in size and shape) that I found in the collections in Okayama a few days ago. As you can see, it is essentially the same size as my own upper arm, yet I am notably not an 8 metre and 6 ton theropod dinosaur (it’s from a sub-adult animal, and admittedly an adult would have been quite a bit bigger, but you get the general idea). In short, tyrannosaurs really do have small arms.