I have read that there were several different Homo species in prehistoric times (H. heidelbergensis, H. neanderthalensis, H. erectus, etc.). Why is it that only the Homo sapiens went from hunter-gatherer to agricultural farming in the Neolithic Revolution, and all the others died out? Maybe the...
Cannibalism has been documented again and again in archaeological contexts, as part of normative human behavior. Here's a recent report (I've not looked yet at the original) from the German Neolithic:
Archaeologists have found evidence of mass cannibalism at a 7,000-year-old human burial site...