An organism with both male and female reproductive organs that produce both male gametes (sperm) and female gametes (ova).

In some animals, the simultaneous hermaphrodites, both male and female organs are functional at the same time. In other animals, the sequential hermaphrodites, one sex develops at one time, which later develops into the other sex. Examples of both strategies are found in nature, especially in the invertebrates, and for many creatures, hermaphroditism is the only method of reproduction.

Many experts believe that true hermaphroditic humans do not exist, but some scientists consider true human hermaphrodites as those who possess one testis and one ovary, even though only one of the two function. Pseudohermaphroditism is a condition in which an individual has both male and female external genital organs, but the gonads are of one sex. Female embryos exposed to high levels of androgens (male hormones) develop female internal reproductive organs but male external genitalia. Alternately, genetic defects cause children to be born with female external genital organs, which change at puberty with the development of a penis and the closure of the false vagina.

Some experts estimate that up to four percent of human births involve some form of variation from what is considered normal male or female morphology. Such infants are usually treated with hormonal medication and surgical intervention as soon as possible to avoid the social and emotional stigma attached to sexual deviation.

For Further Study

Books

Elia, Irene.

The Female Animal.

New York: Henry Holt, 1988.

Periodicals

Berreby, D. "Sex and the Single Hermaphrodite."

Discover 13,

1992, pp. 88-93.

Fausto-Sterling, Anne. "Focus on Only Two Sexes Is Narrow."

The Brown University Child and Adolescent Behavior Letter 10, July 1994, p. 1.