homosexualityltransgender
*Coe, M. J. (1967) “‘Necking’ Behavior in the Giraffe.” Journal of Zoology, London 151:313–21.
*Dagg, A. I., and J. B. Foster (1976) The Giraffe: Its Biology, Behavior, and Ecology. New York: Van Nostrand Reinhold.
*Innis, A. C. (1958) “The Behavior of the Giraffe, Giraffa camelopardalis, in the Eastern Transvaal.” Proceedings of the Zoological Society of London 131:245–78.
Langman, V. A. (1977) “Cow-Calf Relationships in Giraffe (Giraffa camelopardalis giraffa).” Zeitschrift fur Tierpsychologie 43:264–86.
*Leuthold, B. M. (1979) “Social Organization and Behavior of Giraffe in Tsavo East National Park.” African Journal of Ecology 17:19–34.
*Pratt, D. M., and V. H. Anderson (1985) “Giraffe Social Behavior.” Journal of Natural History 19:771–81.
———(1982) “Population, Distribution, and Behavior of Giraffe in the Arusha National Park, Tanzania.” Journal of Natural History 16:481–89.
———(1979) “Giraffe Cow-Calf Relationships and Social Development of the Calf in the Serengeti.” Zeitschrift fur Tierpsychologie 51:233–51.
*Spinage, C. A. (1968) The Book of the Giraffe. London: Collins.
IDENTIFICATION: A deer-sized mammal with distinctive, sharply forked horns in males and reddish brown fur with white patches. DISTRIBUTION: West-central United States, adjacent areas of Canada and Mexico. HABITAT: Prairies, deserts. STUDY AREAS: Yellowstone National Park and National Bison Range, Montana; subspecies A.a. americana.
Social Organization
Pronghorn society is characterized by a distinction between territorial males, who establish territories and mate with females, and nonterritorial males, who live primarily in bachelor herds of seven to ten individuals throughout the spring and into early fall. Females associate in groups of up to two dozen individuals, often accompanied by a territorial male. After the breeding season—during which males copulate with multiple partners and do not assist in parenting—most Pronghorns join large mixed-sex herds for the winter.
Description
Behavioral Expression: Male Pronghorns court and mount each other in their bachelor herds from April to October, using many of the same behavior patterns found in heterosexual courtship and mating. As a prelude to sexual behavior, one male follows another, sometimes sniffing his anal region. The courting male might then touch his chest to the other male’s rump, a signal that he wants to mount. Usually this leads to a full mount, in which the courting male rises on his hind legs and, with erect penis, slides up onto the other male from behind. Sometimes a whole string or “chain” of courting males forms as each follows and tries to mount the male in front of him. Males of all age groups participate in homosexual courtship and mounting, although adult males usually direct their attentions to adolescent males. Mounting between males sometimes occurs during sparring or play-fighting as well. Female Pronghorns also rump-sniff and mount each other when they are in heat, though less frequently than males.
Male Pronghorns shed their horns after the breeding season and some researchers have suggested that this allows them to “pass” as females in mixed-sex herds during the winter. Since males are usually physically exhausted after the rut, they make easier targets for predators than females: by engaging in a form of female mimicry or transvestism, they may avoid being singled out.
Frequency: Overall, about 7 percent of all courtship/sexual behavior is between animals of the same sex, and about 10 percent of all mounts are homosexual (roughly two- thirds of these are between males). Among animals of the same sex, approximately 3–4 percent of their interactions involve some sort of sexual behavior.
A male Pronghorn mounting another male
Orientation: Anywhere from two-thirds to three-quarters of the male population does not participate in breeding; many of these animals are exclusively homosexual. Two-year-old males, for example, never mount females, yet bachelors participate in nearly a third of all homosexual mounts. At the other end of the scale, territorial males are exclusively heterosexual. In between, various forms of bisexuality occur. About 7 percent of adult bachelor males are able to mate with females, yet they also account for 18 percent of homosexual interactions. Some males transfer from the bachelor herds to territorial status, thereby participating in sequential bisexuality over the course of their lives. Many males, however, never become territorial, and though they may try to court females, most of their sexual behavior will continue to be homosexual for the majority—if not the totality—of their lives.
Nonreproductive and Alternative Heterosexualities
As described above, the majority of the male population is not involved in procreation, living as they do in bachelor herds or as loners, and Pronghorn social life is characterized by sex segregation for six to seven months of the year. Some bachelors, however, do try to court females; although their advances are consistently rebuffed, the males often persist and may harass the females relentlessly by chasing them, horning and roaring at them, and sometimes even knocking them down during a chase. Reproduction in the Pronghorn is also characterized by aggression within the womb: procreation routinely involves embryos killing each other. As many as seven embryos may initially be present in the female’s uterus, but only two of these will survive. The remainder are killed by the other developing fetuses, which grow long projections out of their fetal membranes that fatally puncture the others and drag them out of the uterus back up into the female’s oviduct. Some embryos also die earlier because they get strangled in the ropelike bodies of the other embryos. The female reabsorbs any embryos that die.
Sources
*asterisked references discuss homosexuality/transgender
Bromley, P. T. (1991) “Manifestations of Social Dominance in Pronghorn Bucks.” Applied Animal Behavior Science 29:147–64.
Bromley, P. T., and D. W. Kitchen (1974) “Courtship in the Pronghorn Antilocapra americana.” In V. Geist and F. Walther, eds., The Behavior of Ungulates and Its Relation to Management, vol. 1, pp. 356–74. IUCN Publication no. 24. Morges, Switzerland: International Union for Conservation of Nature and Natural Resources.
Geist, V. (1990) “Pronghorns.” In Grzimek’s Encyclopedia of Mammals, vol. 5, pp. 282–85. New York: McGraw-Hill.
Geist, V., and P. T. Bromley (1978) “Why Deer Shed Antlers.” Zeitschrift fur Saugetierkunde 43:223–31.
*Gilbert, B. K. (1973) “Scent Marking and Territoriality in Pronghorn (Antilocapra americana) in Yellowstone National Park.” Mammalia 37:25–33.
*Kitchen, D. W. (1974) “Social Behavior and Ecology of the Pronghorn.” Wildlife Monographs 38:1-96.
O’Gara, B. W. (1978) “Antilocapra americana.” Mammalian Species 90:1–7.
———(1969) “Unique Aspects of Reproduction in the Female Pronghorn (Antilocapra americana Ord.)” American Journal of Anatomy 125:217–32.
