Humans are really good at throwing things. That’s what separates us from chimpanzees. Well, that and single malt Scotch.
How good are we? Well, an adult male chimp can hurl things (like faeces) at thirty kilometres an hour, but human teenagers can easily double that. IN fact, of all the primates, only humans can throw things with great speed and accuracy.
A recent study by Neil Roach, a biological anthropologist at George Washington University used high-speed motion cameras to film twenty college athletes throwing. They then handicapped the athletes with therapeutic braces, constraining their arms such that their range of motion was limited to what early hominids could achieve, based on the fossil record.
They concluded that muscle power only accounts for half of throwing power; the remaining amount comes anatomical features evolved by modern humans (our flexible waists, orientation of the shoulder joint, extended range of motion, etc) that help store kinetic energy. The paper concludes that selection for throwing for the purposes of hunting probably played a role in the evolution of hominids.
That isn’t to say that the modern baseball pitch is a direct result of our spear-throwing past; merely that our spear-throwing past allows for the modern baseball pitch. In conclusion, here’s Matt Cain whipping fastballs at targets.