Biological Exuberance: Animal Homosexuality and Natural Diversity

mounting in Grant’s Gazelles typically occurs as part of a formalized display in which two males march toward one another, lifting their heads high and showing their white throat patches when they are next to each other. The mounted male, if an adult, often attacks the male trying to mount him (females also sometimes respond aggressively to a male’s advances, see below).

Frequency: Male homosexual activity is common among Blackbucks: at any given time, fully three-quarters of the male population lives in the bachelor herds, where most homosexual interactions take place. Among Thomson’s and Grant’s Gazelles, homosexual behavior is much less frequent: 12 percent of encounters between male Grant’s involve mounting, while 1–8 percent of encounters between male Thomson’s involve sexual behavior.

Orientation: All Blackbuck males over three years old leave the bachelor herd temporarily to attempt mating with females. However, this usually occurs only once or twice in each male’s lifetime; for the remainder of his life, he interacts homosexually. Technically, then, all male Blackbuck are bisexual, though in practice they are predominantly homosexual. In Thomson’s Gazelles, homosexual mounting typically occurs among males in bachelor or migratory groups, not territorial males (who are involved principally in heterosexual activities). Although these males occasionally court and attempt to mount females, the majority of their sexual interactions may be with other males. In Grant’s males, homosexual behavior does occur in some territorial males; since these males direct sexual behaviors toward both males and females, they are functionally bisexual (although males generally do not consent to being mounted by other males).

Nonreproductive and Alternative Heterosexualities

Because of the organization of Blackbuck society into sex-segregated herds and the small number of active breeding males, only a fraction of the male population is ever involved in heterosexual activity. Furthermore, although all males attempt to leave the bachelor herds and mate with females, most are unable to do so because of the males already defending the breeding territories; consequently life in the bachelor herd is preferable for many males. Among Grant’s and Thomson’s Gazelles, there are similar patterns of sex segregation and nonparticipation in heterosexuality—in fact, more than 90 percent of the male Grant’s population may be composed of nonbreeders at any given time. In addition, female Grant’s Gazelles often behave aggressively toward males during heterosexual courtship, performing threat displays and sometimes even fighting bucks to fend off unwanted advances. Female Blackbucks sometimes engage in nonreproductive mounts of fawns or young animals.

Sources

*asterisked references discuss homosexuality/transgender

*Dubost, G., and F. Feer (1981) “The Behavior of the Male Antilope cervicapra L., Its Development According to Age and Social Rank.” Behavior 76:62–127.

*Schaller, G. B. (1967) The Deer and the Tiger. Chicago: University of Chicago Press.

Walther, F. R. (1995) In the Country of Gazelles. Bloomington: Indiana University Press.

*———(1978a) “Quantitative and Functional Variations of Certain Behavior Patterns in Male Thomson’s Gazelle of Different Social Status.” Behavior 65:212–40.

*———(1978b) “Forms of Aggression in Thomson’s Gazelle; Their Situational Motivation and Their Relative Frequency in Different Sex, Age, and Social Classes.” Zeitschrift fur Tierpsychologie 47:113–72.

*———(1974) “Some Reflections on Expressive Behavior in Combats and Courtship of Certain Horned Ungulates.” In V. Geist and F. Walther, eds., Behavior in Ungulates and Its Relation to Management, vol. 1, pp. 56–106. IUCN Publication no. 24. Morges, Switzerland: International Union for Conservation of Nature and Natural Resources.

———(1972) “Social Grouping in Grant’s Gazelle (Gazella granti Brooke, 1827 [sic])” in the Serengeti National Park.” Zeitschrift fur Tierpsychologie 31:348–403.

*———(1965) “Verhaltensstudien an der Grantgazelle (Gazella granti Brooke, 1872) im Ngorogoro-Krater [Behavioral Studies on Grant’s Gazelle in the Ngorogoro Crater].” Zeitshcrift fur Tierpsychologie 22:167-208.

WILD SHEEP, GOATS, AND BUFFALO

BIGHORN SHEEP

IDENTIFICATION: A large wild sheep (weighing up to 300 pounds) with massive spiral horns in males; coat is brown with a white muzzle, underparts, and rump patch. DISTRIBUTION: Southwestern Canada, Rocky Mountains to northern Mexico. HABITAT: Mountain and desert rocky terrain. STUDY AREAS: Banff National Park, Alberta; Kootenay National Park and the Chilcotin-Cariboo Region, British Columbia, Canada; National Bison Range, Montana; subspecies O.c. canadensis, the Rocky Mountain Bighorn, and O.c. californiana, the California Bighorn Sheep.

THINHORN SHEEP

IDENTIFICATION: Similar to Bighorn, except smaller and with thinner horns; coat is all white or brownish black to gray, DISTRIBUTION: Alaska, northwestern Canada. HABITAT: Rocky alpine and arctic terrain. STUDY AREAS: Kluane Lake, the Yukon; Cassiar Mountains, British Columbia, Canada; subspecies O.d. dalli, Dall’s Sheep, and O.d. stonei, Stone’s Sheep.

ASIATIC MOUFLON

IDENTIFICATION: Similar to N. American wild sheep, except coat varies from reddish brown or black-brown to light tan, and males may have a light saddle patch and a “bib” or chest mane; horns can be up to 4 feet long, spiral or arching back. DISTRIBUTION: Southwest Asia (including Iran, Afghanistan, Pakistan); Corsica, Sardinia, Cyprus; vulnerable. HABITAT: Hilly or steep terrain, from deserts to mountains. STUDY AREAS: Bavella, Island of Corsica, France; Salt Range near Kalabagh, Pakistan; Johnson City, Texas; subspecies O.o. musimon, the European Mouflon, and O.o. punjabiensis, the Punjab Urial.

Social Organization

Mountain Sheep live in sex-segregated bands, usually numbering 5–15 individuals. During the rutting season, the sexes intermingle and mate promiscuously (males copulate with multiple partners and do not form long-term pair-bonds or participate in parenting).

Description

Behavioral Expression: In Bighorn and Thinhorn Sheep, males live in what one zoologist has described as “homosexual societies” where same-sex courtship and sexual activity occur routinely among all rams. Typically an older, higher-ranking male will court a male younger than him, using a sequence of stylized movements. Same-sex courtship is often initiated when one male approaches the other in the LOW-STRETCH posture, in which the head and neck are lowered and extended far forward. This might be combined with the TWIST, where the male sharply rotates his head and points his muzzle toward the other male, often while flicking his tongue and making growling or grumbling sounds. The courting ram often performs a FORELEG KICK, stiffly snapping his front leg up against the other male’s belly or between his hind legs. He also occasionally sniffs and nuzzles the other male’s genital area and may perform LIP-CURLING or FLEHMEN, in which he samples the scent of the other male’s urine by retracting his upper lip to expose a special olfactory organ. Thinhorn rams may even lick the penis of the male they are courting. The male being courted sometimes rubs his forehead and cheeks on the other ram’s face—even licking and nibbling him—and may also rub his horns on the other male’s neck, chest,