Biological Exuberance: Animal Homosexuality and Natural Diversity

CEREMONY involving clitoral

A younger female Spotted yena (with erect clitoris) mounting an older female in southern Africa.

Two female Spotted Hyenas nuzzling and sniffing each other’s genitals during the “meeting ceremony”; note the erect clitoris and “scrotum” of the female raising her leg.

erection and genital licking: two females stand parallel to each other but with their heads in opposite directions so that they can access each other’s genitals. One or both of them lifts up her hind leg and allows the other to sniff, nuzzle, and lick her erect clitoris and “scrotum”—sometimes for as long as half a minute at a time— occasionally accompanied by a soft groaning or whining sound. Although meeting ceremonies are sometimes performed between males and females (or between two males), they are most common between females.

Frequency: All adult female Spotted Hyenas have enlarged clitorides and labial “scrota.” Homosexual mounting probably occurs only occasionally in this species, although the majority of meeting ceremonies—anywhere from 55—95 percent—occur between adult females.

Orientation: Most females who participate in same-sex mounting and meeting ceremonies are probably functionally bisexual (if not predominantly heterosexual), also mating with males.

Nonreproductive and Alternative Heterosexualities

The female Spotted Hyena’s reproductive anatomy and genitals are not optimal for breeding. Heterosexual mating is often difficult, as males have trouble locating and penetrating the clitoral opening. In addition, many females (and infants) suffer severe trauma and even death during the birth process. Because there is no vaginal canal, Hyenas must give birth through the clitoris itself—an extraordinarily painful process, considering that the newborn’s head is significantly larger than the diameter of the clitoris. This causes the clitoral head to rupture in all females during their first birth, and it is estimated that about 9 percent of females in the wild die during their first labor. In addition, the newborn must travel an extraordinarily long way through the female’s birth canal, which makes a 180-degree turn to exit through the clitoris. Because the umbilical cord is less than a third of the length of the birth canal, many babies suffocate during birth—perhaps as many as 60 percent of infants are stillborn to first- time mothers, and a female’s lifetime production of offspring may be reduced by as much as 25 percent because of such complications. Once born, up to a quarter of Spotted Hyena youngsters may be killed by their siblings, who are fiercely competitive and aggressive toward one another. Infanticide (usually by females) also occasionally occurs among Spotted Hyenas, and cannibalism has been reported as well. Most males do not breed at all: the social system of Spotted Hyenas is such that only one male in a clan gets to mate with the females (although other males may participate in heterosexual courtship). Some males, unable to copulate, engage in a form of “masturbation” in which they thrust their penis in the air and spontaneously ejaculate; others have been seen mounting cubs.

Other Species

Homosexual mounting occurs in Dwarf Mongooses (Helogale undulata), a weasel- like carnivore of Africa. In one group studied in captivity, 16 percent of mounting took place between animals of the same sex (mostly males, including brothers), and some individuals had preferred partners with whom they interacted most frequently. Homosexual behavior has also been observed in two other species of small carnivores: male Common Raccoons (Procyon lotor) and female Martens (Martes sp.).

Sources

*asterisked references discuss homosexuality/transgender

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*Frank, L. G. (1996) “Female Masculinization in the Spotted Hyena: Endocrinology, Behavioral Ecology, and Evolution.” In J. L. Gittleman, ed., Carnivore Behavior, Ecology, and Evolution, vol. 2, pp. 78–131. Ithaca: Cornell University Press.

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*Rasa, O. A. E. (1979a) “The Ethology and Sociology of the Dwarf Mongoose (Helogale undulata rufula).” Zeitschrift fur Tierpsychologie 43:337-406.