...In little more than a single century from 1820 to 19450, no less than fifty-nine million human animals were killed in inter-group clashes of one sort or another.... We describe these killings as men behaving "like animals," but if we could find a wild animal that showed signs of acting this way, it would be more precise to describe it as behaving like men.

Sexual behavior in our species goes through three characteristic phases: pair formation, precopulatory activity, and copulation, usually but not always in that order. The pair-formation stage, usually referred to as courtship, is remarkably prolonged by animal standards.

This gives the agents of the gods a powerful area of support. All they need to do is to remind their followers constantly of their mortality and to convince them that the afterlife itself is under the personal management of the particular gods they are promoting. The self-protective urges of their worshippers will do the rest.

Biologically speaking, if something bites you it's more likely to be female.

Under crowded conditions the friendly social interactions between members of a group become reduced, and the destructive and aggressive patterns show a marked rise in frequency and intensity.

Artists like cats; soldiers like dogs.

We may prefer to think of ourselves as fallen angels, but in reality we are rising apes.