Evidence from the Boxgrove (England) excavations show that hominids were capable of killing large animals already 500000 years ago. There are other ways to hunt than running up a prey and hit it with a stick. Probably animals were not so afraid of people in those times. I have a theory about expansion waves. When early humans first learned to hunt, the animals where not more afraid of them than of chimpanzees, so they were easy to hunt. After some time only the ones with the trait to flee from man would remain. So man had to move to new hunting areas, where animals were still not so scared. But also some people remained and after some time developed better hunting techniques. So they could get the game that was a little harder to hunt. And after some hundreds of thousands of years it was time to move again, into areas occupied by more "old fashioned" people. And so on. The inventions and environmental pressure has in this way been highest in the kernel area, Africa, and new "versions" of Homo has spread from there in the need for game that was easy enough to get. - Hans