Even with these parameters in place, however, an enormous amount of ground must still be covered. In addition to discussing an extensive array of species (nearly 300 mammals and birds), the book draws upon more than two centuries of scientific research. Some of the findings reported here in a few sentences represent literally lifetimes of work on the part of biologists, who often devote their entire careers to studying one very specific and complex aspect of one type of behavior, in one particular population of one particular species. With this in mind, the book should be seen not as a final, definitive pronouncement on the subject, but rather as a beginning or overture, an invitation to further research and discussion.
Any account of homosexuality and transgender in animals is also necessarily an account of human interpretations of these phenomena. Because animals cannot speak directly for themselves the way people can, we must rely on human observations of their behavior. This presents both special challenges and unique advantages to the study of the subject. On the one hand, certain behaviors such as sexual acts can be observed directly (and even quantified), which is often extremely difficult, impossible, or unethical to do in studies of sexuality among people (especially stigmatized or alternative forms of sexuality). On the other hand, we are in the dark about the internal experiences of the animal participants: as a result, the biases and limitations of the human observer—in both the gathering and interpretation of data—come to the forefront in this situation. In many ways this is the reverse of what occurs in some studies of homosexuality among people (including well-informed historical or anthropological studies of different cultures or time periods). With people, we can often speak directly to individuals (or read written accounts) about what their sexuality and associated phenomena mean—and so get a sense of their emotional and motivational states—without necessarily being able to verify their actual sexual behaviors. With animals, in contrast, we can often directly observe their sexual (and allied) behaviors, but can only infer or interpret their meanings and motivations. As a result, many contentious assertions, theories, interpretations, and explanations have been put forward (and continue to be made) within the field of zoology about the function(s) and meaning (s) of homosexuality and transgender. This book seeks to address this historical and very human dimension of the subject, while still maintaining a focus on the animals, their behaviors and lives.
The unique historical moment we find ourselves in also necessitates the book being geared as much as possible toward specialist and nonspecialist alike, and informs the organization and two-part structure of the book. Because of the current inaccessibility of a large body of scientific information, a primary aim is to present the technical material to a general (nonacademic) readership, without sacrificing accuracy or sensationalizing what is often a controversial and difficult subject matter. However, because no comprehensive survey (and synthesis) of this material is yet available within the scientific literature—indeed, many zoologists are themselves unaware of much of this material—and because a considerable amount of misinformation and misunderstanding surrounds the subject even among trained biologists, the volume will also be of interest to the scientific community. Consequently, every effort has been made to provide full documentation in the form of notes and references, and to include relatively exhaustive and detailed coverage of a wide range of species. However, this more technical material is positioned in such a way that it can easily be skipped by readers who do not wish to delve into such matters.
In a book such as this which is intended for both an academic and a nonacademic readership, the question of terminology poses special challenges. I have attempted to steer a course between more accessible but overly anthropomorphic or loaded vernacular, on the one hand, and more “neutral” but highly technical jargon or awkward circumlocutions, on the other. In particular, homosexual(ity) and same-sex are utilized as the labels of choice. Since the words gay and lesbian are burdened with human connotations (cultural, psychological, historical, and/or political) and may not be regarded as appropriate designations for animals, I have been careful to avoid using these terms throughout most of the book (as pointed out in chapter 1). When referring specifically to animals and their behaviors, for example, gay is never employed, while lesbian is used only sparingly (it occurs in less than 3 percent of the more than 3,000 instances in the text where animal homosexuality is named). Even then, lesbian is usually reserved only for cases of linguistic expedience, when alternate phrasings such as “female homosexual(ity)” or “same-sex … among/between females” would become repetitive, cumbersome, or otherwise infelicitous.
Nevertheless, it is important to recognize that a precedent has been established within the zoological discourse for using the less “neutral” (or more culture-bound) designations. The words gay and lesbian are applied by scientists to animals and their behaviors in a number of scholarly publications spanning the past quarter century, including three separate instantiations in the prestigious journal Nature. As in Biological Exuberance, lesbian is more widely used than gay, e.g., “lesbian females” in Fruit Flies (Cook 1975), a “lesbian pair” in Black-billed Magpies (Baeyens 1979), a Common Chimpanzee behaving “in a lesbian fashion” (de Waal 1982),“gay” Snow Geese (Diamond 1989), “gay courtship” in Long-legged Flies (Dyte 1989), “lesbian behavior” in Bonobos (Kano 1992), “lesbian pairs” in Black Stilts (Reed 1993), “lesbian females” in Lesser Flamingos (Alraun and Hewston 1997), “lesbian copulations” in Oystercatchers (Heg and van Treuren 1998); see chapter 3. As for other terms such as transvestism and transsexual(ity), these are also used in the zoological literature with meanings largely divorced from their human connotations (though other labels are employed as well, such as male/female mimicry or sequential hermaphroditism).
It should also be pointed out that the term homosexual—which many people feel is preferable to gay or lesbian when referring to animals—is not devoid of anthropomorphism. It too is a culture-specific, historical construction with very particular human connotations (the same for other putatively “neutral” designations such as hermaphroditism, mimicry, etc.). In fact, a wide variety of terms used routinely in the zoological literature—e.g., courtship, parent(ing), monogamy, adoption, consort(ship) or, for that matter, heterosexual, male, etc.—carry the same baggage of human referents. In addition, the range of variation between (and within) animal species in behaviors that are labeled with the same terms is sometimes as great as—if not greater than—the variation in corresponding behaviors between animals and people. In other words, the differences between “mothers” (or “homosexual copulations”) in flies and chimpanzees probably equal if not exceed the differences between “mothers” (or “homosexual copulations”) in chimpanzees and humans. Yet such terms are applied to a wide range of animals with the understanding that a given word can have variant meanings in different contexts, and that the human connotations are specifically not implied when such vocabulary is used in a zoological context. This issue is discussed more fully in chapter 3, where I offer a careful rationale for the continued use of such terms—specifically with reference to the supposedly anthropomorphic/centric label homosexual and the historical reluctance of zoologists to utilize even this designation.