Our sex is ultimately laid down by our genes. - Jared Diamond

In particular, while natural selection favors both males and females that leave many offspring, the best strategy for doing so may be different for fathers and mothers. That generates a built-in conflict between the parents, a conclusion that all too many humans don’t need scientists to reveal to them. We make jokes about the battle of the sexes, but the battle is neither a joke nor an aberrant accident of how individual fathers or mothers behave on particular occasions. It is indeed perfectly true that behavior that is in a male’s genetic interests may not necessarily be in the interests of his female co-parent, and vice versa. That cruel fact is one of the fundamental causes of human misery.

People often ask, "What is the single most important environmental/population problem facing the world today?" A flip answer would be, "The single most important problem is our misguided focus on identifying the single most important problem!"

History, as well as life itself, is complicated; neither life nor history is an enterprise for those who seek simplicity and consistency.