From that period until the early 21st century, intersex individuals were termed true hermaphrodites if their gonadal tissue contained both testicular and ovarian tissue, or pseudohermaphrodites if their external appearance (phenotype) differed from sex expected from internal gonads. This language has fallen out of favor due to misconceptions and pejorative connotations associated with the terms, and also a shift to nomenclature based on genetics. The term intersex describes a wide variety of combinations of what are considered male and female biological characteristics. Intersex biology may include, for example, ambiguous-looking external genitalia, karyotypes that include mixed XX and XY chromosome pairs (46XX/46XY, 46XX/47XXY or 45X/XY mosaic). Clinically, medicine currently describes intersex people as having disorders of sex development, a term vigorously contested. This is particularly because of a relationship between medical terminology and medical intervention.Intersex civil society organizations, and many human rights institutions, have criticized medical interventions designed to make intersex bodies more typically male or female. In some cases, intersex traits are caused by unusual levels of sex hormones, which may be the result of an atypical set of sex chromosomes. One possible pathophysiological explanation of intersex in humans is a parthenogenetic division of a haploid ovum into two haploid ova. Upon fertilization of the two ova by two sperm cells (one carrying an X chromosome and the other carrying a Y chromosome), the two fertilized ova are then fused together resulting in a person having dual genitalial, gonadal (ovotestes) and genetic sex.
Once a social hierarchy is established a fish changes sex according to its social status, regardless of the initial sex, based on a simple principle: if the fish expresses subordinate behavior then it changes its sex to female, and if the fish expresses dominant or not subordinate behavior then the fish changes its sex to male.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 (or homogamous) is an adult organism that has both male and female sexual organs at the same time. Simultaneous hermaphrodites can be regarded as both sexes present in the same individual. Self-fertilization often occurs. 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 from early spring through late autumn. Banana slugs are another example of a hermaphroditic gastropod.