It may or may not be due to fibromyalgia.
Even fungi that are anisogamous are all hermaphroditic, which is why even anisogamous fungi are considered to be mating types rather than sexes.
Aquatic animals Further information: Most aquatic animals such as and mate using , where the eggs and sperm are released into, and combine within, the surrounding water.
Both anisogamy and isogamy are found in free-living protozoa.
This size disparity may be associated with the cost of producing egg cells, which requires more nutrition than producing sperm: larger females are able to produce more eggs.
New York: Columbia University Press.