Homosexual “Role-Playing”: Gender Blending and Amalgamation

In many animals gender roles of some sort do exist in homosexual interactions, but it is overly simplistic to consider these mere replicas of male and female behaviors. Gendered activities in a same-sex context are never an exact copy of heterosexual roles, and in many cases animals actually exhibit a complex mixture of male and female behavior patterns. This type of gender-role mixing assumes three basic forms: a continuum among individuals, role-differentiated combinations, and behavioral amalgams.²³ In some species, individuals vary along a scale or continuum in the extent to which their behaviors in homosexual interactions resemble “male” or “female” patterns. In Kob antelope, for example, some females utilize the full array of courtship patterns typically employed by males, others make use of none or few of these, while most females range somewhere in between these extremes.²⁴ Ruff males fall into four categories along a spectrum of most “malelike” to most “femalelike” in terms of appearance (presence and color of neck ruff, size), aggressive behavior, courtship behaviors, and other characteristics. However, these categories cut across aspects of sexual behavior, including participation in the “male” role of mounter and the “female” role of mountee in homosexual interactions. The most “malelike” males (residents) perform both roles as do the most “femalelike” males (naked-napes), while of the intermediate categories, some participate in both roles (satellite males) and some rarely engage in either (marginal males). In a number of species such as Gorillas, Hanuman Langurs, and Rhesus, Bonnet, and Pig-tailed Macaques, some individuals clearly prefer (or end up mostly participating) in the “mounter” as opposed to the “mountee” roles during same-sex activity, while for other individuals the reverse is true. Yet these patterns represent the two poles of a continuum, since many individuals in these species actually fall along the entire range in terms of their mounting activities.²⁵

To specifically address the question of “pseudoheterosexual” roles, scientists studying homosexual pairing in Western Gulls made detailed observations regarding whether one partner is more “feminine” and the other more “masculine,” in terms of which courtship, sexual, and territorial behaviors they exhibit. They found that most females employ a mixture of typically male and typically female patterns, although pair-bonds vary in the extent to which there is role differentiation between the partners. In some pairs, one bird performs the majority of mounting and courtship feeding (typically “male” activities) and less “head-tossing” (a typically “female” courtship behavior). In others, there is less of a distinction between the two partners, while in still others the two females participate nearly equally in gendered behaviors. Overall, however, scientists found that both partners in homosexual pairs are more similar to heterosexual females than to males in terms of the amount of time they spend on their nesting territories and their aggressive responses to intruders.²⁶

Another pattern of gender mixing involves role-differentiated combinations, in which same-sex interactions are largely gendered or separated into “male” and “female” roles, yet each individual still combines elements of both to varying degrees. This is a crossing or intermixing of “masculine” and “feminine” traits—in the domains of sexual, courtship, or parenting and pair-bonding behaviors—set against an overall pattern of polarity between the two. For example, male couples in Hooded Warblers often divide up their parenting duties into typically male and female roles: one male builds the nest and incubates the eggs (“female” duties) while the other defends the territory and sings (“male” activities). Yet layered on top of this are more subtle meldings of gender roles: the more “feminine” partner may also engage in the typically male activity of singing (although with a distinctive song type), while the more “masculine” partner may also feed his mate during incubation (an activity rarely exhibited by either partner in heterosexual pairs).²⁷

Other examples related to pair-bonding and parenting activities abound. The “masculine” partner in some Canada Goose (and Chiloe Wigeon) lesbian couples still carries out the quintessentially female activities of egg laying, incubation, and nest-building (the latter usually done only by females in these species). One female in Orange-fronted Parakeet homosexual pairs typically performs the “male” activity of nest-tunnel excavation, yet both partners may initiate courtship feeding (characteristic of males in opposite-sex pairs). And in Mute Swan female pairs, one partner stands guard and defends the territory (like a male), yet both females lay eggs (and both build the nest, typical also of both partners in heterosexual pairs). Some Lovebirds in same-sex pairs are role-differentiated, while others engage in combinations of “male” and “female” courtship and sexual activities. In either case, though, if two females are involved, they both perform the typically “female” roles of nest-building, egg laying, and incubation, while neither of two paired males shows any interest in nest-building (which is not characteristic of either heterosexual role). Some “feminine” partners in Chaffinch lesbian couples also exhibit characteristically male behavioral patterns such as singing, while both partners in role-differentiated Jackdaw homosexual couples (or trios) preen each other—a behavior typical only of females in heterosexual pairs. Similar patterns are to be found where sexual and courtship activities are concerned as well. In Long-eared Hedgehog lesbian interactions, for example, one female may be more “malelike” in initiating and carrying out various courtship and sexual behaviors, yet both partners may perform characteristically “female” invitation postures or typically “male” mounting attempts. Likewise, in courtship interactions between male Victoria’s Riflebirds or Blue-backed Manakins, the more “femalelike” partner that is being courted often responds with his own distinctly male display patterns.²⁸

A final type of gender-role mixing seen in homosexual interactions involves behavioral amalgams—more balanced combinations of “male” and “female” traits in the same individual, a sort of behavioral “androgyny.” This can involve sexual activities: during homosexual interactions between male Gorillas, for instance, the mounter (i.e., the animal “playing the male role”) usually also “plays the female role” of initiating the interaction (female Gorillas typically initiate sexual activity in heterosexual contexts). Mallard females who perform the “male” activity of mounting other females nevertheless display postcopulatory behaviors typical of females, while the mountee in male Black-crowned Night Heron homosexual encounters may perform typically “male” courtship behaviors. The mounter in Hanuman Langur female homosexual encounters often exhibits otherwise “female” behaviors such as initiating the sexual interaction and grooming her partner following the mount. Behavioral amalgams can also involve courtship and parenting activities. When one male Emu is courting another, for example, he stretches his neck and erects his neck feathers—a behavior characteristic of both females and males in heterosexual courtships²⁹—yet neither male makes the booming vocalization typical of females, and each may follow the other (usually only males follow females in heterosexual courtships). Younger male Swallow-tailed Manakins that are courted by adult males exhibit a combination of male and female behavioral traits that makes them distinct from either (and also parallels their plumage, which is a mixture of adult male and female appearance). Their vocalizations and participation in some noncourtship displays are distinctly masculine, while their generally quiet and inconspicuous demeanor is unlike adult males, and in courtship interactions they may assume the role that the female usually does.³⁰ In Snow Goose homosexual pairs, both females perform typically female activities such as incubation and typically male activities such as defense of the goslings.³¹

A multiplicity of gender-role mixtures that defy categorization into any of these three types is the norm in species like the Black-headed Gull. Detailed comparisons of both heterosexual and homosexual pairs showed that birds in same-sex pairs exhibit neither stereotypically “male” nor “female” behaviors. Rather, the frequency with which they perform various courtship and pair-bonding activities tends to be distinct from, or intermediate between, that of both males and females in opposite-sex pairs. For example, the maximum rate of “ceremonial encounters” (a type of courtship interaction) in homosexual pairs exceeds that of both partners in heterosexual pairs. On the other hand, rates of “long-calling” and “head-flagging” (other forms of courtship) tend to be intermediate between those of heterosexual males and females, while the rate of courtship “begging” by males in homosexual couples is generally as low as that of males in heterosexual pairs (which itself is generally lower than that of heterosexual females).³² In addition, both males in homosexual pairs usually build the nest (which is a typically “male” activity in heterosexual couples), although there is also variation between individuals in this regard, with only one partner contributing to the nest in some male pairs.

The “pseudoheterosexual” interpretation of animal behavior offers striking parallels to stereotypical views about human homosexuality. Scientific puzzlement over assigning animals “male” or “female” roles echoes the refrain often heard by gay and lesbian people, who are frequently asked, “Which one plays the man (or woman)?” The assumption is that homosexual relationships must be modeled after heterosexual ones—a view that is as narrow a conception of human relationships as it is of animal sexuality. Each partner in a gay or lesbian relationship (or sexual encounter) is thought to “play” one-half of a heterosexual couple. In reality, far more complex and multidimensional expressions of gender categories are involved, even (or perhaps especially) when the partners appear most “heterosexual” to outside observers. Some people do not structure their homosexual interactions along gendered lines at all; others do, but re-create typically “male” and “female” patterns in new configurations. To give just one example: butch-femme lesbian relationships have long been viewed as simplistic imitations of heterosexuality, in which the butch partner is the “man” and the femme partner is the “woman.” Lesbians whose erotic lives are organized along these lines, however, describe eloquently how their actual experiences are far different from this. Neither partner is “copying” heterosexual roles; rather, each is taking elements of masculinity and femininity and alloying them in different combinations and intensities to create female-specific genders. As one lesbian has said about the kind of women she is attracted to, a masculine lesbian is not an imitation man, but a real butch.³³ If even this most superficially “heterosexual” gender presentation is more than what it appears, imagine the possibilities when homosexual interactions are gender-role-defined in other ways, or not at all. Such “possibilities” are in fact everyday realities in the lives of both humans and animals.

Over the past thirty years, a sophisticated analysis of gender categories has been emerging from within the feminist, gay and lesbian, and transgender movements, one that challenges basic notions such as “male” and “female,” “masculine” and “feminine,” “mannish” and “effeminate.” These movements are also calling for a recombining and reimagining of categories such as these, rather than simply their denigration or abolishment. Unfortunately, zoologists for the most part are still operating under an earlier, outmoded conception of gender roles (both heterosexual and homosexual)—one that is inconsistent with the actualities of sexual and gender expression within the animal and human worlds. If any progress is to be made in the study and understanding of animal homosexuality and transgender, scientists and nonscientists alike will need to acquire the sort of multifaceted view of gender and sexuality that is now being articulated within these human liberation movements.

“The Lengths to Which Deprived Creatures Will Go”—Homosexuality as Substitute Heterosexuality

One of the most prevalent myths about animal homosexuality is that it is invariably caused by a shortage of members of the opposite sex. This is typically attributed to skewed sex ratios in the population (more males than females, or vice versa), or the unavailability of opposite-sex partners due to sex segregation, hostility or indifference on the part of potential mates, or other factors. This belief is widespread among nonscientists and is also the most common “explanation” that biologists have proposed for the occurrence of homosexual behavior in animals. In more than 65 species of mammals and birds, for example, same-sex activity is claimed by zoologists to result from individuals being “unable” to mate heterosexually. Sometimes this is attributed to a predominance of one sex over the other in wild or captive populations: the formation of lesbian pairs in Australian Shelducks and Ring-billed Gulls, for instance, is supposedly “caused” by an excess number of females (65 percent females in Shelduck populations, 55 percent females in Ring-billed Gulls).

Homosexual pairs in Mute Swans occurring in populations with unbalanced sex ratios are said to be “examples of the lengths to which deprived creatures will go to satisfy their natural urge to reproduce.” In some cases, homosexual behavior is labeled a “substitute” for heterosexuality or “redirected” heterosexual behavior, resulting from a variety of factors. For example, it is claimed that individuals are “prevented” from mating with (or otherwise having access to) the opposite sex by other (often higher-ranking) animals, or by the overall social organization (e.g., in Mountain Sheep, Bottlenose Dolphins, or Killer Whales). Alternatively, it has been suggested that individuals resort to homosexuality when their heterosexual advances are met with refusal or disinterest (e.g., in White-handed Gibbons, West Indian Manatees, Asiatic Elephants). In a few cases (e.g., Hanuman Langurs, Lions, Sage Grouse) scientists have even suggested that females turn to one another because they have not been “satisfied” or received enough attention from male partners—a version of the widespread stereotype about the “cause” of lesbianism among people.³⁴

The line of reasoning in “explanations” such as these is curious, since it implies that unless there is an adequate supply of the opposite sex, homosexuality will inevitably ensue. This is actually an unintentional assertion of the relative strength of the homosexual urge, or correspondingly, the relative weakness of the heterosexual imperative—for the stronghold of heterosexuality must be tenuous indeed if such factors are capable of upsetting the balance. Besides this, however, unavailability of the opposite sex—what we will call the shortage hypothesis—is simply incompatible with the facts.

Surplus Homosexuality

The shortage hypothesis cannot be a universal explanation for animal homosexuality because of the many examples of animals engaging in same-sex activity when opposite-sex partners are freely available.³⁵ In Orang-utans, Japanese Macaques, Stumptail Macaques, Rhesus Macaques, Common Gulls, Black-headed Gulls, King Penguins, Galahs, and more than 40 other species, scientists have documented individuals either ignoring opposite-sex partners and seeking out same-sex partners instead, or else engaging in homosexual activity more or less concurrently with heterosexual activity (i.e., even when opposite-sex partners are accessible, as already mentioned in the discussion of simultaneous bisexuality).³⁶ In fact, in a surprisingly large number of species, homosexual activity is positively correlated with heterosexual activity: same-sex interactions actually increase as animals gain access to opposite-sex partners and decrease in their absence. This is the exact reverse of what would be expected if homosexuality resulted from a lack of access to heterosexual mating opportunities.

Homosexual activity among male Bottlenose Dolphins in captivity, for instance, actually declined when females were removed from their tank, while aggressive interactions between the males increased. Conversely, female Squirrel Monkeys in one study engaged in virtually no homosexual activity when kept in same-sex groups, yet showed significant rates of homosexual mounting and other activities (along with heterosexual behaviors) when males were introduced into their group. Another study of this species found that females with the most attention from heterosexual partners also engaged in the most homosexual pursuits. In Bonobos, Stumptail Macaques, Savanna (Yellow) Baboons, and West Indian Manatees, same-sex activity is often stimulated by opposite-sex activity (and vice versa), with the result that sessions may involve both heterosexual and homosexual encounters among multiple participants. Homosexual mounting in Pukeko is most prevalent in breeding groups that have the greatest amount of heterosexual activity, while homosexual mounts in Common Murres become more common as promiscuous heterosexual mounts also increase in frequency (although the latter may, ironically, result from a decrease in available females). In some species, individuals that participate in the most heterosexual matings may also engage in the most homosexual ones, as in Sociable Weavers and Bonnet Macaques. Conversely, animals that are the least active heterosexually are often the least active homosexually. In Ruffs, for example, the class of males who do not generally mate with females (known as marginal males) also rarely participate in homosexual matings, while in one study of Japanese Macaques, the only female who did not consort with any other females also failed to consort with any males.³⁷ Finally, in a number of species such as Swallows, Laysan Albatrosses, and Herons, same-sex mounting occurs primarily among breeding individuals (i.e., those who already have heterosexual mates) and is largely absent among nonbreeders.

A number of species do have skewed sex ratios, but (like dominance) this is neither a sufficient nor a necessary prerequisite for the occurrence of homosexuality in a population. Male homosexuality is not reported for red-winged blackbirds or giant cowbirds, for example, even though some populations are 80-84 percent male, nor for pintail duck populations with two-thirds males, or kiwis with 58 percent males, or purple finches with 57 percent males. Likewise, female homosexuality is absent in boat-tailed grackles even though males may comprise only a third of the population, and in sparrow hawks, where there is also a “surplus” of females (less than 40 percent males). In contrast, homosexuality occurs in numerous species or populations that have equal (or nearly equal) sex ratios, including Bonobos, Bonnet Macaques, West Indian Manatees, Snow Geese, California Gulls, and Pukeko.³⁸ Moreover, closely related species or different populations of the same species that have identical (or similar) sex ratios and forms of social organization often exhibit strikingly different patterns of homosexuality. Many Seals and Sea Lions with polygamous mating systems, for instance, have strongly female-biased sex ratios (three to five females for every male) and social systems that often include sex segregation and/or exclusion of large numbers of males from breeding opportunities. Some of these species exhibit male homosexuality (e.g., Gray Seals, Northern Elephant Seals, Walruses), others have female homosexuality (e.g., Northern Fur Seals), some have both (e.g., Australian Sea Lions), while the majority have no homosexuality at all (e.g., California sea lions, southern fur seals). Likewise, lunulated antbirds, salvin’s antbirds, Bicolored Antbirds, and Ocellated Antbirds all live in populations that have an excess of males, yet homosexual pairing is only found in the latter two species.³⁹

In many animals that have skewed sex ratios, homosexuality only occurs (or is more common) in the sex that is in shorter supply rather than in the “surplus” sex. In some populations of Crab-eating Macaques, for example, females outnumber males by more than two to one, yet same-sex activity only occurs among males. Female homosexuality accounts for more than 80 percent of same-sex activity in Pukeko even though some populations are more than 70 percent male. The reverse is true for Rhesus Macaques: in some populations females outnumber males nearly three to one, yet the majority of same-sex activity (over 80 percent) is between males. Tree Swallow populations often have a surplus of females, but only male homosexuality occurs. Likewise, female pairs have formed in captive populations of Galahs and Scarlet Ibises that have an excess of males, while male pairs of Flamingos are reported from populations that have more females than males. In Nilgiri Langurs, there is a female-biased sex ratio in the overall population (and individuals live in groups with more females than males), yet only male same-sex activity is reported. Finally, in Little Egrets and Little Blue Herons there is a “surplus” of unpaired males, yet same-sex mounting occurs almost exclusively among paired males rather than in the population of birds that are unable to find heterosexual mates.⁴⁰

While homosexual activity in some species may appear to be associated with an unavailability of the opposite sex, the patterns of its occurrence are often far more complex than a shortage explanation would indicate. Although lesbian pairs in Black Stilts, for example, generally do occur in populations where the sex ratio is biased toward females, in other populations of the same species with a surplus of males, no male homosexual pairs have formed. The same is true, in reverse, for captive Humboldt Penguins: male pairs form when there is a surplus of males but female pairs do not form when there is a surplus of females. Among some populations of Savanna (Yellow) Baboons, the sex ratio becomes skewed among older juveniles, where males outnumber females two to one—and indeed, 10 percent of such animals’ mounting is homosexual. However, the sex ratio is equal among adults and younger juveniles, and the prevalence of homosexual mounting in these segments of the population is the exact opposite of what the shortage hypothesis would predict: 17-24 percent of their mounting is same-sex. In other words, older juvenile males actually exhibit the lowest proportion of homosexual activity and the greatest participation in heterosexual mounting of any segment of the population (accounting for more than half of all male-female mounts), even though their age group contains the greatest surplus of males. Sex ratios in wild Mallard Ducks fluctuate during the breeding season, with fewer females being present in some months than others. Although male pairs sometimes form at these times, during other months when there is also an excess of males in the population, there are no male pairs.⁴¹

If access to heterosexual mates were the only factor involved in the occurrence of homosexuality, both males and females in sex-segregated populations should exhibit the same degree of homosexual activity. However, in the majority of species that have some form of sex segregation, homosexual activity is found in only one sex (e.g., Walruses, Gray Seals, Warthogs, American Bison) or is much more common in one sex (usually males) than the other (e.g., Giraffes, Blackbucks, Mountain Sheep, Australian Sea Lions). Conversely, in some species that have unbalanced sex ratios (in wild or captive contexts), such as Pig-tailed Macaques, Bottlenose Dolphins, Cheetahs, Koalas, Canada Geese, and Flamingos, homosexuality occurs in both sexes (although it may be more common in the “surplus” sex). This indicates that more is involved than simply a “shortage” of available heterosexual partners.⁴² Likewise, where populations of the same species vary in their sex ratios, homosexuality is sometimes less common in nonskewed populations, but it is still present. In Japanese Macaques, Giraffes, and Greylag Geese, for example, same-sex activity may increase in populations with an excess of one sex, but it still occurs at a fairly steady rate in other circumstances regardless of the sex ratio and may even be present in the “limiting” sex (e.g., in Giraffe populations with more than 60 percent females, male homosexuality still occurs). Even in populations of Japanese Macaques with highly skewed sex ratios, most individuals still manage to participate in both heterosexual and homosexual activities, indicating that they are not turning to same-sex partners as a result of being completely “deprived” of opposite-sex partners.⁴³

Similarly, in a number of species where homosexuality sometimes occurs in the absence of opposite-sex partners (due to sex segregation, heterosexual refusal, captive situations, etc.), same-sex activity is not limited to these contexts, but also occurs in mixed-sex groups (e.g., Gorillas, Hanuman Langurs, Crested Black Macaques, Squirrel Monkeys, Walruses, Lions, Mallard Ducks, Black-headed Gulls) or in contexts where it is not a response to the refusal or unavailability of the opposite sex (e.g., West Indian Manatees, Cheetahs).⁴⁴ If same-sex activity were due entirely to an absence of the opposite sex, it should disappear completely once opposite-sex partners are available, yet these examples show that it does not. Conversely, homosexuality does not arise automatically or immediately when animals are deprived of opposite-sex partners, nor does heterosexuality necessarily ensue once they have access to such partners. Homosexual activity in a captive group of female Squirrel Monkeys, for instance, did not develop until fully one year after they had been sequestered away from males, while female Long-eared Hedgehogs that were homosexually involved with each other in the absence of males did not participate in heterosexual mating for more than two years after they were given access to males.⁴⁵

Multiple Possibilities

Even if homosexuality in some species only occurs in populations where there is more of one sex than the other, this is, at the very least, evidence of a “latent” bisexual capacity among some individuals. Moreover, the skewed sex ratio is probably only a contributing factor rather than a determining “cause” of same-sex interactions in such cases. Typically only a portion of the “surplus” sex in these populations actually participates in homosexuality, and sometimes “available” opposite-sex partners are even passed over. This is most obvious in Silver Gulls, where nearly half of all females are “unable” to find a male partner each year, yet lesbian pairs constitute only about 6 percent of the population—in other words, the vast majority of “surplus” females remain single rather than forming homosexual pairs. Furthermore, about 14 percent of all males are unpaired, which means that females who form same-sex bonds do so in spite of the presence of single males in the population. Likewise, some female Mallard Ducks remain unpaired even in populations with more males than females. In one semi-wild population of Canada Geese with an excess of males, some of the unpaired males failed to form homosexual pairs; furthermore, some females also remained unpaired or formed homosexual bonds even though opposite-sex birds were “available.” While approximately 10 percent of widowed Jackdaws form homosexual pair-bonds, the majority of widowed birds who do not find male partners actually remain single rather than pairing with female partners. Lesser Scaup Duck populations generally consist of 60-80 percent males, yet only a fraction of these individuals engage in homosexual mounting (and none form homosexual pair-bonds). Similarly, herds of Caribou may contain only 30-40 percent males, yet same-sex activity among females is not overwhelming.⁴⁶ Other species in which only a portion of the “surplus” individuals form same-sex bonds include Flamingos, Laughing Gulls, Humboldt Penguins, Gentoo Penguins, Pied Kingfishers, Peach-faced Lovebirds, Galahs, and Bicolored Antbirds.⁴⁷

Although homosexual involvements in such species may be the “result” of skewed sex ratios, any “explanation” of homosexuality that relies on this factor alone needs to address why only some individuals “choose” this strategy, and why this strategy rather than another. For in addition to remaining single or forming same-sex pair-bonds, a wide variety of other behavioral responses occur among animals in populations that have a surplus of one sex, or in situations where the opposite sex is “unavailable.” For example, in many otherwise monogamous species that have more females than males (or vice versa), some individuals form polygamous heterosexual trios (so-called “bigamy”) or even quartets (“trigamy”). These options occur alongside homosexual pairings in Flamingos and Humboldt Penguins, and instead of same-sex pairing in Cattle Egrets, emperor penguins, and dippers (among many others). Individuals in the same population may also adopt different strategies or combine these strategies, to varying degrees: in Oystercatcher communities, for instance, with large surpluses of nonbreeding birds unable to find heterosexual mates or breeding territories of their own, only a small fraction of these birds form polygamous trios (most remain unmated); and only a portion of these in turn go on to develop homosexual bonds within their trio. Australian noisy miners (a bird species with a heavily male-biased sex ratio) have developed a complex, specieswide system of communal breeding that involves, among other arrangements, polyandry (several males associating with each female, without any same-sex bonding). The reverse situation occurs in spotted sandpipers, in which “surplus” birds actually participate in monogamy rather than polygamy. In this species, females usually mate with several males and generally leave the parenting duties to them; females unable to find polygamous mates, however, often “revert” to monogamous (heterosexual) pairing and parenting, helping one male partner with incubation and brooding.⁴⁸

Polygamy is just the tip of the iceberg as far as alternate strategies are concerned. Surplus female Redshanks participate in promiscuous matings with already paired males rather than forming bonds involving other females; “extra” male mustached warblers help already established pairs raise their families; while surplus female Ostriches and Greater Rheas lay their eggs in other females’ nests or abandon them rather than forming bonds with either males or females. Female Tree Swallows, male tropical house wrens, and male barn swallows unable to find mates of their own often invade the nests of existing heterosexual pairs and forcibly acquire a partner (either through direct attack and eviction of the other mate, or by killing their young and causing the pair’s breakup). In some species of Penguins and Egrets, individuals form temporary or serial heterosexual pair-bonds or divorce their partners more often in response to a surplus of one sex. In Black Stilt populations with a surplus of one sex, birds regularly seek heterosexual partners outside their species (hybridizing with the closely related Black-winged Stilt), while female Silver and Herring Gulls in some colonies with a “shortage” of adult males often simply pair with much younger males. A common response of male African Elephants that are sexually aroused but unable to find receptive female partners is simply to roll in mud wallows or take dust baths (thereby perhaps “diffusing” their arousal), rather than engaging in any sexual behavior (with either males or females). In all of these species, homosexual activity (if it occurs at all) is simply one “option” that some individuals adopt alongside many other alternatives.⁴⁹

A shortage explanation cannot adequately account for the occurrence of such multiple strategies, or for the choice of one over the other. By claiming that animals “resort” to homosexuality in times of need, scientists often overlook other more plausible (heterosexual) alternatives—unintentionally providing support for the idea that homosexuality may actually be the most appealing option for some individuals in these circumstances. For example, homosexual activity in White-handed Gibbons has been attributed to the unavailability (or unwillingness) of a male’s female partner to have sex with him. But why don’t such males seek heterosexual matings outside of their pair-bond or simply masturbate (strategies that both occur in other contexts for this species)? Likewise, homosexual courtships in Ostriches are claimed—in a particularly convoluted sequence of logic—to result from a balanced sex ratio in some populations. Because Ostriches often mate polygamously—one male with several females—a population that has equal numbers of males and females would supposedly be unable to support such multiple matings. One scientist suggested that in this case males turn to their own sex—but why would this occur instead of males simply remaining in monogamous heterosexual pairings (as do spotted sandpipers)? Some same-sex mountings in Buff-breasted Sandpipers are said to result from the scarcity of females late in the breeding season. But once females stop visiting the breeding territories at this time, males often move their courtship displays to where the females are (at their nests) and may even copulate with them during the egg-laying period. Why would some males “resort” to relocating their heterosexual activities, while others would “abandon” them for homosexual activities?⁵⁰ Even if same-sex activity in these species could be attributed to the unavailability of the opposite sex, important questions such as these remain unaddressed under a shortage explanation. On the other hand, if participation in homosexuality is seen as the expression of individual variability and plasticity in sexual orientation—rather than as being “caused” or “determined” by a shortage of the opposite sex—then the variety of sexual responses and capacities actually seen in such circumstances is no longer incongruous.