Definition and meaning of Hermaphrodite

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In a biological context, a hermaphrodite is an animal or plant that has both male and female reproductive organs.^[1]

Many taxonomic groups of animals (mostly invertebrates), do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both partners can act as the "male" or "female". For example, the great majority of pulmonate and opisthobranch snails and slugs are hermaphrodites. Hermaphroditism is also found in some fish, and to a lesser degree in other vertebrates.

Historically, the term hermaphrodite has also been used to describe ambiguous genitalia and gonadal mosaicism in individuals of gonochoristic species, especially human beings. The term comes from the name of the minor Greek god Hermaphroditus, son of Hermes and Aphrodite. Recently, intersex has been used and preferred by many such individuals, encouraging medical professionals to use the term.^[2]

Zoology

Sequential hermaphrodites

Sequential hermaphrodites (dichogamy) occur in species in which the individual is born as one sex, but can later change into the alternate sex.^[3] This is in contrast with simultaneous hermaphrodites, in which an individual may possess fully functional male and female gonads. Sequential hermaphroditism is common in fish (particularly teleost fish), many gastropods (such as the common slipper shell), and some flowering plants. While some sequential hermaphrodites can change sex multiple times, most can only change sex once.^{[citation needed]} Sequential hermaphrodism is important in understanding behavioral ecology and life history theory.

Sequential hermaphrodites fall into two broad categories:

• Protandry: Where an organism is born as a male, and then changes sex to a female.^[3]
  • Example: The clownfish (Genus Amphiprion) are colorful reef fish found living in symbiosis with sea anemones. Generally one anemone contains a 'harem', consisting of a large female, a smaller reproductive male, and even smaller non-reproductive males. If the female is removed, the reproductive male will change sex and the largest of the non-reproductive males will mature and become reproductive. It has been shown that fishing pressure can change 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 natural selection.
• Protogyny: Where the organism starts as a female, and then changes sex to a male.^[3]
  • Example: wrasses (Family Labridae) are a group of reef fish in which protogyny is common. Wrasses also have an uncommon life history strategy, which is termed diandry (literally, two males). In these species, two male morphs exists: an initial phase male or a terminal phase male. Initial phase males do not look like males and spawn in groups with other females. They are not territorial. They are perhaps, female mimics (which is why they are found swimming in group with other females). Terminal phase males are territorial and have a distinctively bright coloration. Individuals are born as males or females, but if they are born males, they are not born as terminal phase males. Females and initial phase males can become terminal phase males. Usually, the most dominant female or initial phase male replaces any terminal phase male, when those males die or abandon the group.

Dichogamy can have both conservation-related implications for humans, as mentioned above, as well as economic implications. For instance, groupers are favoured fish for eating in many Asian countries and are often aquacultured. Since the adults take several years to change from female to male, the broodstock are extremely valuable individuals.

Simultaneous hermaphrodites

A simultaneous (or synchronous) hermaphrodite (homogamy) is an adult organism that has both male and female sexual organs at the same time.^[3] Usually, self-fertilization does not occur.^{[citation needed]}

• Reproductive system of gastropods: Pulmonate land snails and land slugs are perhaps the best-known kind of simultaneous hermaphrodite, and are the most widespread of terrestrial animals possessing this sexual polymorphism. Sexual material is exchanged between both animals via spermatophore, which can then be stored in the spermatheca. After exchange of spermatozoa, both animals will lay fertilized eggs after a period of gestation; then the eggs will proceed to hatch after a development period. Snails typically reproduce in early spring and late autumn.

Banana slugs are one example of a hermaphroditic gastropod. Mating with a partner is more desirable biologically, as the genetic material of the resultant offspring is varied, but if mating with a partner is not possible, self-fertilization is practised. The male sexual organ of an adult banana slug is quite large in proportion to its size, as well as compared to the female organ. It is possible for banana slugs, while mating, to become stuck together. If a substantial amount of wiggling fails to separate them, the male organ will be bitten off (using the slug's radula), see apophallation. If a banana slug has lost its male sexual organ, it can still mate as a female, making its hermaphroditic quality a valuable adaptation.

• 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 a simultaneous 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. Sexual reproduction occurs when two worms meet and exchange gametes, copulating on damp nights during warm seasons. Fertilized eggs are protected by a cocoon, which is buried on or near the surface of the ground. a

Pseudohermaphroditism

Female Hyenas have a clitoris that is greatly enlarged, so much so, that they were described as hermaphrodites — not only by the ancient Greeks, but as recently as the twentieth century among circus animal handlers — until scientific information was provided that clarified the misunderstanding.^{[citation needed]}

Botany

Hermaphrodite is used in botany to describe a flower that has both staminate (male, pollen-producing) and carpellate (female, ovule-producing) parts. This condition is seen in many common garden plants. A closer analogy to hermaphrodism in animals is the presence of separate male and female flowers on the same individual—such plants are called monoecious. Monoecy is especially common in conifers, but occurs in only about 7% of angiosperm species (Molnar, 2004).

Other uses of the term

Hermaphrodite was used to describe any person incompatible with the biological gender binary, but has recently been replaced by intersexual in medicine. Humans with typical reproductive organs but atypical clitoris/penis are called pseudohermaphrodites in medical literature.

People with intersex conditions sometimes choose to live exclusively as one sex or the other, using clothing, social cues, genital surgery, and hormone replacement therapy to blend into the sex they identify with more closely. Some people who are intersexed, such as some of those with Klinefelter's syndrome and androgen insensitivity syndrome, outwardly appear completely female or male already, without realizing they are intersexed. Other kinds of intersex conditions are identified immediately at birth because those with the condition have a sexual organ larger than a clitoris and smaller than a penis. Intersexuality is thought by some to be caused by unusual sex hormones; the unusual hormones may be caused by an atypical set of sex chromosomes.

Sigmund Freud (based on work by his associate Wilhelm Fliess) held fetal hermaphroditism 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 sexuality on that assumption. Similarly, in contemporary times, fetuses before sexual differentiation are sometimes described as female by doctors explaining the process.^[4] Neither concept is technically true. Before this stage, humans are simply undifferentiated and possess a Müllerian duct, a Wolffian duct, and a genital tubercle.

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 individual possessing physical traits of both sexes. Thus, Hermaphroditus could be called, using modern terminology, a simultaneous hermaphrodite. The mythological figure of Tiresias, who figures in the Oedipus cycle as well as the Odyssey, could be called a sequential hermaphrodite, having been changed from a man to a woman and back by the gods.

In fiction

• The Greek mythical figure, Tiresias, appears in many classical and modern works, including the Odyssey, Oedipus the King and the Divine Comedy.
• Julia Ward Howe's unfinished novel The Hermaphrodite, written probably in 1846-1847, features a protagonist, a biological hermaphrodite, who is raised as a man but also spends some time living as a woman. He faces crises of identity and the problems of fitting into European gender roles of the period.
• Robert A. Heinlein's 1959 short story "—All You Zombies—" is the tale of a (simultaneous yet sequential, by means of surgery to expose hidden male sex organs and remove damaged female organs) hermaphrodite who manages, via time travel, to impregnate his earlier outwardly female self who in turn gives birth to herself.
• Ursula K. Le Guin's novel, The Left Hand of Darkness, featured a planet inhabited by humans whose ancestors had modified themselves to be sequential hermaphrodites. For twenty-four days of each twenty-six day lunar cycle, they were sexually latent androgynes, and for the remaining two days were male or female, as determined by pheromonal negotiation with an interested sex partner.
• The 1990 Michael Crichton science fiction novel, Jurassic Park, and its 1993 film adaptation featured dinosaurs exhibiting a sequential hermaphrodite transformation as a key plot point. The ability of the scientists to maintain control over the park's cloned dinosaur population was derived by preventing the dinosaurs from developing a Y chromosome while in fetal development, thus ensuring that they were all females. However, the scientists used DNA of some other animals with sequential hermaphroditic abilities to complete fragmented portions of the dinosaurs' DNA, allowing some of them to become male in adulthood and mate. However, dinosaurs probably had the bird type of sex chromosome system, with ZZ for male and WZ for female, see: ZW sex-determination system.
• The 1993 Gary Jennings novel, Raptor, features Thorn, a hermaphrodite, as its main character.
• Baron Ashura, one of the Dr. Hell's henchmen in Mazinger Z series, is a hermaphrodite.
• The Star Trek: New Frontier series features the Hermat species, including Burgoyne 172. Hermats possess both male and female characteristics.
• In Nabari no Ou, Yoite was a hermaphrodite whose mother died giving birth to him.
• In Star Wars, Hutts are hermaphrodites.
• In Episode 17 of Freaks and Geeks, Amy, the girlfriend of Seth Rogen's character Ken, reveals that she was born with both male and female genitalia, but received an operation to become female.
• The 2002 novel, Middlesex, is narrated by its protagonist, Calliope Stephanides, who is a true hermaphrodite.
• In South Park's Season 2, Episode 2, "Cartman's Mom Is Still a Dirty Slut", Dr. Mephisto reveals that Mrs. Cartman is a hermaphrodite.
• In the video game Spore, all creatures are hermaphrodites.
• In the novel and manga adaption of the Ring (Ringu), Sadako Yamamura is told to be a hermaphrodite; that is, she has no uterus, but she identifies as female and has testes along with breasts.
• In the early 1990s, Channel 4, a British television channel, showed a four-minute program in the late evening called "Hermaphrodite Bikini", where a few hermaphrodites danced naked to music.
• In the video game, Zeno Clash, one of the main characters, Father-Mother is a initially believed to be a hermaphrodite. This belief is proven to be false near the conclusion of the game.
• In the anime series, Yu-Gi-Oh! GX, the character/Duel Monsters spirit Yubel is a hermaphrodite. In the dub, however, she is censored and said to be female.
• Most life forms on the fictional planet Darwin IV are hermaphrodites.
• The short story "Cinismo" by Argentinean writer Sergio Bizzio, (in Spanish [1]) and the 2007 movie XXY, based on that story.
• In the anime adaptation of Black Butler (Kuroshitsuji), the maid, Angela, is a hermaphrodite; she and 'Ash' are the same person.
• In the futuristic novel "Crygender" (published 1992), by Thomas T. Thomas, the title character is a wealthy hermaphrodite.^[5]

See also

• Androgyny
• Gonochorism

Notes

References

• "Bony Fishes: Reproduction". SeaWorld/Busch Gardens Animal Infobooks. Busch Entertainment Corporation. 2009. http://www.buschgardens.org/animal-info/info-books/bony-fish/reproduction.htm. Retrieved 12 September 2009. 
• Discovery Health Channel, (2007) "I Am My Own Twin"
• Kim M.D., Kyu-Rae; Youngmee Kwon M.D., Jae Young Joung M.D., Kun Suk Kim M.D., Alberto G Ayala M.D. and Jae Y Ro M.D. (2002). "True Hermaphroditism and Mixed Gonadal Dysgenesis in Young Children: A Clinicopathologic Study of 10 Cases". Modern Pathology (Nature Publishing Group) 15 (10): 1013–1019. doi:10.1097/01.MP.0000027623.23885.0D. ISSN 0893-3952. OCLC 357415945. PMID 12379746. http://www.nature.com/modpathol/journal/v15/n10/full/3880645a.html. Retrieved 12 September 2009. 
• Randall, John E. (2005). Reef and Shore Fishes of the South Pacific: New Caledonia to Tahiti and the Pitcairn Islands. Honolulu, Hawaii: University of Hawaii Press. pp. 346, 387. ISBN 0-8248-2698-1. OCLC 52152732. 

Further reading

• Chase, Cheryl (1998). "Affronting Reason". in Atkins, Dawn. Looking Queer: Body Image and Identity in Lesbian, Bisexual, Gay, and Transgender Communities. New York: Haworth Press. pp. 205–219. ISBN 978-1-56023-931-4. OCLC 38519315. 
• Fausto-Sterling, Anne (12 March 1993). "How Many Sexes Are There?". The New York Times (New York): p. Op-Ed. , reprinted in: Harwood, Sterling, ed (1996). Business As Ethical and Business As Usual: Text, Readings, and Cases. Belmont, CA: Wadsworth Pub. pp. 168–170. ISBN 0534542514. OCLC 141382073. 
• Grumbach, Melvin M.; Conte, F. A. (1998). "Disorders of sex differentiation". in Williams, Robert Hardin; Wilson, Jean D. Williams Textbook of Endocrinology. Philadelphia: Saunders. pp. 1303–1425. ISBN 0-7216-6152-1. OCLC 35364729. 
• Molnar, Sebastian (17 February 2004). "Plant Reproductive Systems". Evolution and the Origins of Life. Geocities.com. http://www.geocities.com/we_evolve/Plants/breeding_sys.html. Retrieved 12 September 2009. 

External links

• "Born True Hermaphrodite - Pictorial Profile", about Lynn Edward Harris
• Hermaphroditism.info