8.9 What about hermaphrodites – and why aren’t they more common?

Some organisms contain male and female gonads (sperm or egg producing organs), and produce both sperm and eggs (see figure X for examples).  These individuals are called hermaphrodites (in plants they are often called monecious). In previous pages, you learned that some fish are sequential hermaphrodites (they change from one sex to the other).  Other organisms are simultaneous hermaphrodites, meaning they can produce both sperm and eggs at the same time.  Examples of such organisms include most plants, some types of snails, worms, slugs, and some fish.  Can you imagine any advantages to one individual having the ability to produce both eggs and sperm?

Note: Hermaphroditism does not exist in humans. While some humans have intersex conditions, they are not hermaphrodites.

  Points to Ponder

How might it be beneficial to an individual to produce both eggs and sperm? Similarly, can you imagine any costs associated with hermaphroditism?