Far far more kills than was necessary for caloric content. This idea that early humans "took only what they needed from nature" is quaint. They took what they could use, which means basically whenever usefulness outweighed the risk of the hunt. I remember an early history class about a buffalo jump. Teacher told us that "all parts of the animal were used." Well, not that giant pile of bones. If the dogs were hungry, or one needed some fresh bones to carve a tool, some large herbavore was killed. Im sure that lots of useful meat was left to the elements, just as with hunters today.