[Happy Monkey]

I'm worried that you will attempt to twist this into some sort of implied justification, since this is a subject that can be difficult to discuss without emotional tension. But yes, just about any behavior that occurs in the animal kingdom has an evolutionary basis, either directly or as a side effect of another strategy. However, humans have developed a more important (IMHO) strategy of empathy and cooperation, that gives us the ability to override any baser animal instincts, and those who don't do so should be considered defective and removed from society.