It's a mistake to think of evolution as producing selfish animals concerned only with their own survival. Altruism abounds in cases where a helping ha

With so many land creatures to wonder at, it's easy to forget that some of the weirdest activities take place deep in the ocean. The strange practice of hermaphroditism is more common among species of fish than within any other group of vertebrates. Some fish change sex in response to hormonal cycle or envirnomental changes. Others simultaneously possess both male and female sex organs.