Biological Exuberance: Animal Homosexuality and Natural Diversity

of female coparenting in Barn Owls was included in a report on “Abnormal and Maladaptive Behavior in Captive Raptors”—part of a monograph on (of all things) diseases in birds of prey. Homosexual activity in Rhesus Macaques was even presented (along with a number of other “abnormal” behaviors) as an illustration of the deleterious effects of malnutrition.⁹³ In a perfect example of the sort of circular reasoning that is employed in many scientific discussions, homosexuality in captive animals is often cited as the “proof” of the artificiality of their captive conditions. One zoologist proclaims, “Homosexual behavior [in Cheetahs] … is reported in zoos as quite frequent, which to me indicates that something is amiss at the zoos,” while another states, “The very occurrence of female-female pairs [in Zebra Finches] suggests behavioral pathology.”⁹⁴ This is chillingly reminiscent of the not-so-distant “medicalized” views of human homosexuality, where the mere existence of same-sex attraction or activity was sufficient to “diagnose” pathology or mental illness.

While it is true that captivity sometimes does induce unusual behaviors in animals, the bulk of the evidence does not support this as a “cause” of animal homosexuality. As primatologist Linda Fedigan observes, “Although … homosexual relationships in animals can occur as a result of stressful captive conditions, we would suggest that all such behavior should not be dismissed as pathological or dysfunctional, a practice which results in ‘explaining it away’ rather than explaining it.”⁹⁵ On statistical grounds alone there is no substantiation for a greater incidence of homosexuality in captive animals—in fact, just the reverse is true. In more than 60 percent of the mammals and birds in which same-sex activity has been documented, this behavior occurs spontaneously in the wild. In more than two-thirds of these species, homosexuality has only been observed in the wild, while in the remaining cases it occurs in both wild and captive animals.⁹⁶ A number of scientists have remarked on a higher rate of homosexual activity in captivity compared to in the wild when the behavior occurs in both situations. In other words, there may be a quantitative, rather than qualitative, difference between wild and captive conditions, although the occurrence of homosexuality itself cannot be attributed to confinement. However, even this difference is less than clear-cut. In some species such as Orang-utans, Hamadryas Baboons, Mule Deer, and Musk-oxen, there does indeed appear to be a higher rate of homosexual courtship and/or sexual activity—as well as heterosexual activity—in captivity compared to the wild, although in some instances this is based on impressionistic observations.⁹⁷ In contrast, two species for which detailed quantitative information is available show nearly identical rates of same-sex activity in the wild versus captivity: in Bonobos, studies of wild animals have revealed that 45–46 percent of all sexual activity is homosexual, while a captive study yielded a figure of 49 percent; in Black Swans, one investigator found that 5 percent of captive pairs were homosexual while 6 percent of wild ones were.⁹⁸

Failure to observe homosexuality in the wild is more often due to incomplete study or inadequate observational techniques rather than an actual absence of the behavior in free-ranging animals. Time and again, same-sex activity has initially been seen only in captive animals and therefore declared to be definitively not a part of the “normal” sexual repertoire of the species in the wild. Yet when detailed field studies of the same species are finally conducted—often decades later—homosexuality is inevitably discovered. In fact, so pervasive or routine is the behavior now known to be for some species in the wild, that scientists have had to completely revise prior assessments of same-sex activity as “artificial” for these animals in captivity. In Bottlenose Dolphins, for example, male pairs engaging in homosexual behavior were originally observed in aquariums and were considered to be the “aberrant” result of keeping males together without females. Detailed longitudinal and demographic studies of the species—more than forty years later—revealed that male pairs, as well as sex segregation, are a prominent feature of the social organization of this species in the wild. By 1998, zoologists were actually advocating that captive male Bottlenose Dolphins be kept (and reintroduced into the wild) as bonded pairs, recognizing that these constitute a “natural functional social unit” of the species that can assist captive individuals in adjusting to life in the wild upon their release. Another example of a complete turnaround on the part of scientists concerns Gorillas. Early studies of this species reported that homosexuality was not seen in wild Gorillas; three decades later, extensive same-sex activity had been documented in both males and females in the mountain forests of Africa. By 1996, biologists and zookeepers were (at last) openly acknowledging that homosexuality in all-male groups was not an “artificial construct of captivity,” and were even encouraging the formation of such groups in zoos to approximate the species’ natural social patterns.⁹⁹

Many other examples of field studies confirming earlier captive observations of homosexuality (and disproving initial assessments of its “artificiality”) can be found. In 1935, Konrad Lorenz asserted that the formation of same- sex pairs in female Jackdaws “does not appear to occur under natural conditions”; it wasn’t until more than forty years later that ornithologists confirmed the occurrence of homosexual pair-bonding in wild Jackdaws. Same-sex activities between male Elephants in captivity were first reported in the scientific literature in 1892 and characterized as “aberrations” and “perversions”; almost 75 years later, similar and more extensive homosexual interactions were documented among wild Elephants. In 1997 zoologists presented the first descriptions of same- sex activities in wild Crested Black Macaques, finally confirming captive observations made more than thirty years earlier. Because no detailed field studies of this species had been conducted before the 1990s, all prior reports of homosexual activity were based on observations in captivity, leading some scientists to suggest that same-sex activity was not likely to be found in wild Crested Black Macaques—a prediction we now know was incorrect. Homosexual pairing in Parrots was long considered to be “induced or brought forth by the conditions of confinement,” but in 1966 an ornithologist documented a male pair of Orange-fronted Parakeets in the forests of Nicaragua—the first confirmation of homosexuality in wild Parrots. Ironically, the sex of the birds was verified only because the scientist mistook them for a heterosexual pair copulating unusually early in the breeding season (and therefore he wanted to check the condition of their internal reproductive organs). Initial observations of homosexuality in captive female Lions, made in 1942, were confirmed in the wild in 1981, while observations of male pairs in wild Great Cormorants in 1992 corroborated early observations of this phenomenon among zoo birds in 1949. Likewise, same-sex courtship in Regent Bowerbirds was first described on the basis of aviary observations in 1905, but display between wild males was not documented until nearly a century later. And homosexual activity between different species of Dolphins, long observed in aquariums, was finally verified in a wild population in 1997.¹⁰⁰ Today, homosexuality in many species is still known only from captive studies, but it is likely that most, if not all, of these will follow this same pattern and eventually be confirmed by field studies. Perhaps it is finally time for scientists to acknowledge that homosexuality in captive animals is nearly always an expression of their normal behavioral repertoire, rather than a result of their captivity.

Another point to keep in mind is that the distinction wild versus captive is in some sense a false dichotomy, since in actuality there is a continuum of degrees of confinement, “artificiality,” and human intervention in the living conditions of animals. At one extreme are truly “wild” animals that have experienced no, or virtually no, contact with humans—an increasingly rare phenomenon in the contemporary world. At the other extreme are domesticated animals that have been bred and raised in captivity for many generations, often to the point of being genetically distinct (as a separate species or subspecies) from their wild counterparts. In between, there is a whole spectrum of contexts and factors. Toward the more “wild” end of the continuum, there are free-ranging species that have nevertheless experienced varying degrees of human contact or interference, such as Killer Whale populations that have been heavily poached, or wild Tree Swallows that nest in colonies of human-supplied nest boxes, or Grizzly Bears living in “disturbed” habitats, or wild Atlantic Spotted Dolphins that are habituated to the presence of people.¹⁰¹ There are also semi-wild animals, a cover term that includes a host of different situations. For instance, unconfined animals may nevertheless be tame (e.g., Greylag Geese), while animals on reserves may be wild or “free-ranging” within a confined but extensive territory, often hundreds or thousands of acres in size (e.g., Bison, Cheetahs). Transplanted populations consist of entire troops or herds that have been moved, their social organization and demographics intact, to a new (often more restricted) environment, sometimes because they are endangered in their natural habitat (e.g., Rhesus Macaque troops transplanted from India to Puerto Rico, Blackbuck herds moved from India to France). Another semi-wild situation involves animals that are recently extinct in the wild and therefore can only be observed in captivity (e.g., Takhi, Pere David’s Deer). In many cases such species are kept in conditions that approximate their “former” wild habitat and social organization as closely as possible, and in some instances they are even being slowly reintroduced to the wild from their captive populations. “Provisioned” animals are wild but supplied with food and varying amounts of human contact (e.g., Japanese Macaques), while “rehabilitated” animals are formerly captive (and possibly wild-born), but reintegrated