Hermaphrodite

[2] The individuals of many taxonomic groups of animals, primarily invertebrates, are hermaphrodites, capable of producing viable gametes of both sexes.

In the great majority of tunicates, mollusks, and earthworms, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male.

According to Ovid, he fused with the nymph Salmacis resulting in one individual possessing physical traits of male and female sexes.

[12] According to the earlier Diodorus Siculus, he was born with a physical body combining male and female sexes.

[16]) This contrasts with simultaneous hermaphrodites, in which an individual possesses fully functional male and female genitalia.

Sequential hermaphroditism can best be understood in terms of behavioral ecology and evolutionary life history theory, as described in the size-advantage mode[17] first proposed by Michael T. Ghiselin[18] which states that if an individual of a certain sex could significantly increase its reproductive success after reaching a certain size, it would be to their advantage to switch to that sex.

A female spotted hyena's apparent penis is in fact an enlarged clitoris, which contains an external birth canal.

[31] The term hermaphrodite is used in botany to describe, for example, a perfect flower that has both staminate (male, pollen-producing) and carpellate (female, ovule-producing) parts.

The 12th-century Decretum Gratiani states that "Whether an hermaphrodite may witness a testament, depends on which sex prevails" ("Hermafroditus an ad testamentum adhiberi possit, qualitas sexus incalescentis ostendit.").

[44][45] Alexander ab Alexandro (1461–1523) stated, using the term hermaphrodite, that the people who bore the sexes of both man and woman were regarded by the Athenians and the Romans as monsters, and thrown into the sea at Athens and into the Tiber at Rome.

"[47][48] During the Victorian era, medical authors attempted to ascertain whether or not humans could be hermaphrodites, adopting a precise biological definition to the term.

This language has fallen out of favor due to misconceptions and stigma associated with the terms,[50][51][8][10] and also a shift to nomenclature based on genetics.

[54] Intersex civil society organizations, and many human rights institutions,[55][56] have criticized medical interventions designed to make bodies more typically male or female.

[62]: 213 A 2023 study argued that hermaphroditism can evolve directly from mating types under certain circumstances, such as if the fertilization is well organized and the average size of groups is small.

[63] Simultaneous hermaphroditism that exclusively reproduces through self-fertilization has evolved many times in plants and animals, but it might not last long evolutionarily.

[66] According to Nelson Çabej simultaneous hermaphroditism in animals most likely evolved due to a limited number of mating partners.

Garden snails mating
Shells of Crepidula fornicata (common slipper shell)
Clownfish are initially male; the largest fish in a group becomes a female.
Most species of parrotfish start life as females and later change into males.
Turbellarians mating by penis fencing . Each has two penises on the undersides of their heads which they use to inject sperm.
Earthworms are simultaneous hermaphrodites, having both male and female reproductive organs.
Photo of a flower with a large orange centre and delicate yellow stigma protruding. The centre is surrounded by white petals and a halo of green and yellow spikes.
Hylocereus undatus , a hermaphrodite plant with perfect flowers that have both functional carpels and stamens .
Intersex flag
Hermaphroditus , the "son" of the Greek god Hermes and the goddess Aphrodite , origin of the word "hermaphrodite"
The Obando Fertility Rites in the Philippines , before becoming a Catholic festival, was initially an Anitist ritual dedicated to the hermaphrodite deity, Lakapati, who presided over fertility. [ 42 ]
1860 photograph by Nadar of a person displaying ambiguous genitalia, one of a nine-part series . The series may be the earliest medical photographic documentation of an intersex person. [ 43 ] : 358