Michael Moore: Hermaphrodite?

A simultaneous hermaphrodite (or synchronous hermaphrodite) is an organism that has both male and female organs at the same time as an adult. Usually, self-fertilization does not occur.

Hamlets, unlike other fish, seem quite at ease mating in front of divers, allowing observations in the wild to occur readily. They do not practice self-fertilization, but when they find a mate, the pair takes turns between which one acts as the male and which acts as the female through multiple matings, usually over the course of several nights.
Earthworms are another example of synchronous hermaphrodite. Although they possess ovaries and testes, they have a protective mechanism against self fertilization and can only function as a single sex at one time. reproduction occurs when two worms meet and exchange tes, copulating on damp, wet nights during warm seasons. Fertilized eggs are protected by a cocoon, which is buried on or near the surface of the ground.
Banana Slugs are one more synchornous hermaphrodite example. Mating with a partner is most desirable, as the genetic material of the offspring is varied, but if mating with a partner is not possible, self-fertilization is practiced. The male part of an adult banana slug is quite large in proportion to its size, as well as compared to the female part. It is possible that while mating, banana slugs can get stuck together. If a substantial amount of wiggling doesn't do the trick, the slug's male part will be bit off (slugs do not have mouths like humans, though - rather, they have a radula). If a banana slug has lost its male member, it can still self-fertilize, making its hermaphroditic quality an invaluable adaptation.