An interesting story in the news: human monogamy may have arisen to protect infants from being killed by male rivals. True or not, there’s a dark vein in there. After all, natural selection isn’t “for” anything. Evolution is just the outcome of successful ways of propagating genes. That means that monogamy just happens to be useful for the survival of the young ‘uns.
But think of this: it also means that the primates who kill babies don’t have any reason to do so. They do it just because. Sound familiar?