Homosexuality in the Service of Heterosexuality

If homosexuality does not enhance reproductive performance or act as a population regulator or “helper” system, then how else might it be evolutionarily “useful”? A number of scientists have suggested some other ways that homosexual behavior could contribute, directly or indirectly, to heterosexual activity and/or breeding. In this section, we’ll look at several of these proposals, including suggestions that homosexuality is a way of practicing heterosexual mating, a method to attract opposite-sex partners, a form of competition to reduce the heterosexual mating opportunities of rivals, and several other more far-fetched “explanations.”

Practicing Homosexuals

Same-sex activity is often claimed to be a way that younger animals practice or “rehearse” heterosexual courtship or mating, or a way for individuals to gain sexual “experience” that will improve their future breeding success.⁴³ While it is possible that homosexuality could provide this “service,” it is unlikely that this is its major function. A serious problem with this proposal—as noted by several scientists—is that in most of these species homosexual behavior is not restricted to younger individuals or those who need to acquire sexual experience.⁴⁴ In some cases, it is found in all age groups (Walruses, Northern Elephant Seals, West Indian Manatees), in others it is more prevalent in younger animals but still occurs in older ones (Killer Whales, Giraffes), while in some cases it continues throughout an individual’s life (Black-headed Gulls).⁴⁵ Moreover, in these and many other species there are frequently other patterns of homosexual or bisexual orientation that stretch the limits of a “practice” interpretation nearly to absurdity. For instance, are animals who engage primarily or exclusively in same-sex activities “practicing” their whole lives for some never-to-be achieved heterosexual opportunity? Or how about individuals who intermingle or alternate between homosexual and heterosexual activity—do they need to constantly return to same-sex behavior for remedial “practice”? And what about animals who “switch” to homosexuality only after they have been involved in heterosexual activity, or who come to homosexuality late in their lives—are their prior heterosexual involvements then “practice” for their homosexual ones?

When faced with these and other examples of homosexuality “persisting” or (re)appearing in adulthood, advocates of the “practice” interpretation have been forced to adopt exactly such unconvincing scenarios. For example, scientists have actually argued that individuals continue to engage in homosexuality as adults so that they can experience differences in sexual behavior across a wide variety of partners (of both sexes) and thereby continue to improve their heterosexual performance—an ironic reversal of the traditional view, in which homosexuality is considered to detract from, or be incompatible with, heterosexuality.⁴⁶ According to this “practice” interpretation, heterosexual “competence” is apparently so elusive (or difficult to achieve and maintain) that it requires constant, albeit indirect, reinforcement through the help of homosexuality. When we examine the realities of animal behavior we find that in many cases heterosexual mating is far from the automatic or “natural” occurrence that it is commonly assumed to be, and it does require some “practice” (see the next section). However, this “explanation” does a disservice to both heterosexuality and homosexuality in its view of the former as unnecessarily tenuous and the later as necessarily derivative.

Even in species where homosexuality is limited to younger animals or to adult-juvenile interactions, there are often serious discontinuities in participation that challenge a practice interpretation. For example, in the Guianan Cock-of the-Rock, homosexual courtship and mating occur between adolescent and adult males and have been classified as “practice” behavior on the part of the younger males. However, there is a curious gap in the age distribution of participating males: primarily one-year-olds are involved, while two-year-olds almost never participate in such activity. Could it be that once they pass the yearling stage, they no longer need any “practice”? Most definitely not: scientists studying this species report that when males first acquire their own territories, between the ages of three and five, they continue to practice their courtship—but largely without homosexual interactions—thereby gaining valuable experience that they will need before embarking on heterosexual mating.⁴⁷ Why should birds first “practice” using homosexuality as one-year-olds, then cease such practice as two-year-olds, only to resume practice without homosexuality as three-to-five-year-olds, and then once again participate in homosexual “practice” sessions with younger males when they become older? And what exactly is the role of the adult males who willingly participate in all of these “practice” sessions? It seems unlikely that they need to “improve” their skills, too, or that they are simply serving as “mentors” to (probably unrelated) males, altruistically providing them with the opportunity to rehearse their mating skills. Although younger males may gain sexual and courtship experience as an indirect result of homosexual interactions, this appears to be a relatively minor by-product of such activity and is highly problematic as an overall “explanation” for the behavior.⁴⁸

There are other questionable aspects to the notion that homosexual behavior is merely rehearsal for heterosexual behavior. In many species where a “practice” interpretation has been suggested, only a small fraction of the population ever engages in same-sex activity, and often an individual participates only a handful of times. It seems highly unlikely that much sexual experience, or any useful “training,” could be gained from such activity.⁴⁹ Moreover, in many species young animals practice heterosexual behavior by participating directly in heterosexuality, either with adults or with each other. In other animals—including ones in which adults engage in homosexuality—heterosexual practice is accomplished without partners or overt same-sex activity. For example, adolescent male Sage Grouse learn the complex courtship display of their species by imitating older males, practicing the “strutting” movements and sounds while they are gathered in their own groups on the periphery of the breeding grounds. Occasionally an older male joins the group so that he can—in the words of one ornithologist—“demonstrate the fine points of strutting to the rapidly maturing novices,” but no homosexual courtship or copulation takes place, and in fact homosexual activity in this species is limited to adult females. Among Montagu’s harriers and several other species of raptors, young birds are trained in heterosexual courtship displays by parents of both sexes without any homosexual activity.⁵⁰ Even if homosexual behavior were training for heterosexuality, this raises more questions than it answers. Why must some animals “resort” to same-sex practice while others can use opposite-sex interactions (or solo practice)? Why does homosexual “training” in some species involve adults “helping” younger animals, while in other species juveniles only “practice” amongst themselves? And why do some individuals apparently not need to “practice” at all? It is clear from these examples that a “practice” interpretation of homosexuality is at best of limited applicability and explanatory value.⁵¹

Finally, there is a curious gender bias in the application of a “practice” interpretation to homosexuality—in the overwhelming majority of cases, only male animals are said to require such rehearsal.⁵² Where complicated courtship displays are performed only by the male of the species, this is perhaps understandable, but why should it be that no female needs to “practice” sexual activity by engaging in same-sex activity? In many animals, especially primates, females are active participants in heterosexual intercourse, often initiating sexual activity and adopting specific postures, positions, or movements as part of a sexual interaction. In most bird species, heterosexual copulation is impossible without the cooperation and active participation of the female: since most male birds do not have a penis, mating can usually only occur if the female actively facilitates the interaction, for example by positioning herself in such a way as to allow genital contact. Yet in none of these species has it been suggested that females “practice” heterosexual mating via homosexual copulation—not because practice isn’t required, or because lesbian activity could not serve this “function,” but because many scientists still regard the female as an essentially passive participant in sexual activity.⁵³ This is highly revealing—not only of sexist attitudes in biology, but also of the true “utility” of this explanation. It is not applied systematically and carefully to all potentially relevant cases: more often than not, it is simply introduced when most other “explanations” have failed, a convenient tool with which to discount or dismiss homosexual activity.