Hermaphrodite

This is an old revision of this page, as edited by RyanFreisling (talk | contribs) at 14:34, 14 October 2006 (rv deletion of 'etymology' section. Please discuss your rationale on 'talk' before blanket deletions like that. Thanks!). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Revision as of 14:34, 14 October 2006 by RyanFreisling (talk | contribs) (rv deletion of 'etymology' section. Please discuss your rationale on 'talk' before blanket deletions like that. Thanks!)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)

This article needs attention from an expert on the subject. Please add a reason or a talk parameter to this template to explain the issue with the article.
When placing this tag, consider associating this request with a WikiProject.

For the Julia Ward Howe novel, see The Hermaphrodite.

For the type of electrical connector, see Gender of connectors and fasteners.

The 1st-century BC sculpture 'The Reclining Hermaphrodite', in the Museo Palazzo Massimo Alle Terme in Rome

In zoology and botany, a hermaphrodite is an organism that possesses both male and female sex organs during its life. In many species, hermaphroditism is a common part of the life-cycle, particularly in some asexual animals and some plants. Generally, hermaphroditism occurs in the invertebrates, although it occurs in a fair number of fish, and to a lesser degree in other vertebrates. Typically, in hermaphrodites belonging to a species in which hermaphroditism is not the norm (humans, for example), reproduction is not possible, but there are some instances in which sperm or ova are capable of conceiving offspring. On very rare occassions, such a hermaphrodite can even impregnate itself, but this will result in complications, such as the offspring having identical DNA to its parent. See Simultaneous Hermaphrodites below.

The term "hermaphrodite" has historically been used to describe people with ambiguous genitalia or biological sex. The broader term inter is often used and is preferred by many such individuals and medical professionals. However, some hermaphrodites do not like the connotations and misunderstanding of the word "Intersexed" and thus prefer to use hermaphrodite instead. The term is still used by the pornography industry, though often as a synonym for transsexual, as true human intersexuals are rare.

In animals

Sequential hermaphrodites

Sequential hermaphrodites are organisms born as one sex which later change into the other sex, and can only function as one sex at one time. A few species in this group can sex change multiple times, but they can only function as one sex at a time.

Protandry: When the organism starts as a male, and changes sex to a female later in life.
- Example: The Clownfish (Genus Amphiprion) are colorful reef fish found living in symbiosis with anemones. Generally one anemone contains a 'harem', consisting of a large female, a small reproductive male, and usually smaller non-reproductive males. If the female is removed, the reproductive male will sex change into a female, and the largest of the non-reproductive males will mature and become reproductive. It has been shown that fishing pressure actually is causing a change in when the switch from male to female occurs, since fishermen naturally prefer to catch the larger fish. The populations are generally changing sex at a smaller size, due to artificial selection.
Protogyny: When the organism starts as a female, and changes sex to a male later in life.
- Example: Wrasses (Family Labridae) are reef fish that are all Protogynous, but have two different life strategies:

For some species, they all start out as females, and when they get large enough they will sex change to males.
Other species start out as females or males (initial phase), and either may shift to become a supermale (terminal phase male). The females and the initial phase males have similar colorations. The supermale is usually brightly colored, and there is only one in a given area of the reef. This supermale dominates the other wrasses of the species, having the choice of females to mate with. When the supermale dies, the largest wrasse in the area, male or female, becomes the new supermale.

Simultaneous hermaphrodites

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.

Gonadal dysgenesis

Gonadal dysgenesis is a type of inter formerly known as "True Hermaphroditism", occurs in about one percent of mammals (including humans), but it is extremely rare for both sets of organs to be functional; usually neither set is functional. In many cases, these manifestations are altered, sometimes only cosmetically, to resemble standard male or female anatomy shortly after birth.

Fetal hermaphroditism in humans

Sigmund Freud (based on work by his associate Wilhelm Fliess) held fetal hermaphroditsm to be a fact of the physiological development of humans. He was so certain of this, in fact, that he based much of his theory of innate on that assumption. This was later revealed to be untrue (see sexual differentiation).

In plants

Hermaphrodite is used in botany to describe a flower that has both staminate (male, pollen-producing) and carpelate (female, seed-producing) parts that are self fertile or self pollenizing. Hermaphrodism in plants is more complex than in animals because plants can have hermaphroditic flowers as described, or unisexual flowers with both male and female types developing on the same individual—a closer analogy to animal hermaphrodism. However, this latter condition constitutes monoecy in plants, and is especially common to the conifers, while occurring in only about 7% of angiosperm species (Molnar, 2004).

Etymology

The term "hermaphrodite" derives from Hermaphroditus, the son of Hermes and Aphrodite in Greek mythology, who was fused with a nymph, Salmacis, resulting in one possessing physical traits of both sexes. Thus Hermaphroditus was, by the modern terminology, a simultaneous hermaphrodite. The mythological figure of Tiresias, who figures in the Oedipus cycle as well as the Odyssey, was a sequential hermaphrodite, having been changed from a man to a woman and back by the gods.

References

Merriam-Webster Dictionary

2. Randall, John E.,(2005) Reef and Shore Fishes of the South Pacific, Univ. of Hawaii Press, p346 and 387. ISBN 0-8248-2698-1

3. SeaWorld/Busch Gardens Animal Information Database, "Fish Reproduction"

Misplaced Pages