"Like ours, the animal world is full of paradoxical examples of gentleness, brutality, and suffering, often performed in the service of reproduction. Female black widow spiders sometimes devour their partners after a complex and delicate mating dance. Bald eagle parents, who mate for life and share the responsibility of rearing young, will sometimes look on impassively as the stronger eaglet kills its sibling. At the end of their life cycle, after swimming thousands of miles in salt water, Pacific salmon swim up their natal, freshwater streams to spawn, while the fresh water decays their flesh. Animals will do whatever it takes to ensure reproductive success." - × × ×