Biological Exuberance: Animal Homosexuality and Natural Diversity

The debate about the “nature” and origin of homosexuality often invokes seemingly opposite categories: genetics versus environment, biology versus culture, nature versus nurture, essentialism versus constructionism. Indeed, the very categories “homosexual” and “heterosexual” are themselves examples of such a dichotomy. By using these categories, biologists and social scientists hope to discover what aspects of homosexuality, if any, are biologically determined. Yet by framing the debate in terms of such categories, it is easy to forget that more complex interactions between factors must be considered. For example, most research shows that both environment and biology are relevant in determining sexual orientation in people (and probably also animals). Some individuals may have an innate predisposition for homosexuality, but the right combination of environmental (including social) factors is required for this to be realized. And how meaningful is it to talk about a culture-nature distinction when, as we have just seen, some animal species have themselves developed forms of cultural behavior? Similarly, by focusing attention on the “causes” of homosexuality, the determinants of heterosexuality are considered irrelevant—or, alternatively, heterosexuality is assumed to be inevitable unless something “goes wrong.” And not all sexuality fits neatly into the categories of exclusive homosexuality or exclusive heterosexuality—the large realm of experience that involves bisexuality is easily glossed over in discussions about the origins of homosexuality/heterosexuality. So, too, with the question of whether homosexuality is “natural” and what its occurrence in animals can tell us about this: things are considerably more complicated than they initially appear.

What is remarkable about the entire debate about the naturalness of homosexuality is the frequent absence of any reference to concrete facts or accurate, comprehensive information about animal homosexuality. Those who argue against the naturalness of homosexuality assert with impunity that same-sex behavior does not occur in nature (like the man quoted above) and is therefore self-evidently abnormal. Those who argue in favor of a biological origin for homosexuality often ignore the complexities of animal behavior arising from social, protocultural, or individual life-history factors (relying on the behavior of laboratory animals injected with hormones, for example, instead of long-term studies of animals interacting in their own social groups or communities).⁷⁶ This is because naturalness is more a matter of interpretation than facts. Now that the widespread occurrence of animal homosexuality is beginning to be documented, little if anything is likely to change in this discussion. More information about same-sex activity in animals simply means more possible interpretations: the information can be used to support or refute a variety of positions on the naturalness or acceptability of homosexuality, depending (as before) on the particular outlook of whoever is drawing the conclusions.

As James Weinrich points out, the only claim about naturalness that is actually consistent with the facts is the following: homosexual behavior is as natural as heterosexual behavior.⁷⁷ What this means is that homosexuality is found in virtually all animal groups, in virtually all geographic areas and time periods, and in a wide variety of forms—as are heterosexuality, divorce, monogamy, and infanticide, among other things. Conversely, heterosexuality is as “unnatural” as homosexuality is, since it often exhibits social elaboration or cultural “embellishment,” as well as many of the “unacceptable” features stereotypically associated with same-sex relations, such as promiscuity, nonreproduction, pursuit of sexual pleasure, and interactions marked by instability, ineptitude, and even hostility.⁷⁸ But whether this means that homosexuality is “biologically determined” and/or “socially conditioned” —and by extension, (un)acceptable in humans—is largely a question of interpretation. Of course, from a scientific perspective, the sheer extent and variety of homosexual expression in the animal world reveals an aspect of nonhuman biology and social organization that is unexpected—one with far-reaching (perhaps even revolutionary) implications. It demands careful consideration and suggests a rethinking of some of our most fundamental notions of environment, culture, genetics, and evolutionary and social development. But to automatically conclude that because homosexuality occurs in animals, it must be biologically determined oversimplifies the debate and does an injustice to the facts.