The Evolution of Throwing Things

So far as we know, only one animal can throw projectiles with enough speed and accuracy to make them deadly weapons: us. Lots of animals sometimes throw things, and chimps sometimes throw things at leopards or baboons. But compared to us they are absurdly clumsy.

I was actually thinking about this the other day on the basketball court, pondering how much subconscious calculation must be involved in lofting a ball into a metal hoop from 20 feet away, something I do without giving the details of the motion any thought whatsoever. My eye is on the basket, and the ball follows it.

When did we evolve this ability? Neil Roach of Harvard and his colleagues have approached this question by analyzing in detail the anatomical underpinnings of throwing. They find that the most important difference between humans and chimpanzees is the reconfiguration of the shoulder so that the tendons can store energy during the back swing and release it during the throw. Based on their study of hominid skeletons, they think the first proficient throwers were Homo erectus, around 2 million years ago.

Fascinating.