employed in the broad sense for these cases, it is always with the understanding that only selected behavior categories or co-occurrences may be involved (as in observations of heterosexual behavior).47
The difference between these two usages of the term
Most scientists are understandably wary of anthropomorphizing animals with terms that have wide applicability in a human context—as well they should be—and obviously not all zoologists who avoid the word
“Not Included in the Tabulated Statistics”
Even when homosexual behavior is recognized as such, detailed study of it is often omitted or passed over, or the phenomenon is marginalized and trivialized. For instance, numerous published reports on the courtship and copulation behavior of animals provide excruciatingly detailed descriptions and statistics on frequency of mounts, number of ejaculations, duration of penile erections, number of thrusts, timing of estrous cycles, total number of sexual partners, and so on and so forth—but all for
Sometimes certain aspects of homosexual activity are excluded or arbitrarily eliminated from an overall analysis or tabulation—often resulting in a distorted picture of same-sex interactions (regardless of whether the omission is deliberate or well-motivated). For instance, a female Western Gull who exhibited the most overt sexual activity with her female partner was “not included in the tabulated statistics” of a study comparing heterosexual and homosexual behaviors. By failing to incorporate data from this individual (intentionally or not), researchers undoubtedly helped foster the (now widely cited) impression that sexual activity is a uniformly negligible aspect of female pairing in this species. Along the same lines, scientists surveying pair formation in Black-crowned Night Herons only tabulated homosexual couples that they considered to be “caused” by the “crowded” conditions of captivity. They ignored a male pair whose formation could not be attributed to such conditions and also overlooked the fact that such “crowded” conditions regularly occur in wild colonies of the same species. And all data concerning same-sex pairs or coparents in Laughing Gulls, Canary-winged Parakeets, Greater Rheas, and Zebra Finches were excluded from general studies of pair-bonding, nesting, or other behaviors in these species.51
The significance of homosexual activity is sometimes also downplayed in discussions of its prevalence or frequency. Certainly many variables must be considered when trying to quantify same-sex activity, and the task is rarely straightforward (as we saw in chapter 1). Nevertheless, in some instances homosexual frequency is interpreted or calculated so as to give the impression that same-sex activity is less common than it really is or else is de-emphasized in terms of its importance relative to other species. In Gorillas, for example, homosexual activity in females is classified as “rare” because investigators observed it “only” 10 times on eight separate days. However, these figures are incomplete unless compared with the frequency of heterosexual interactions during the same period. In fact, 98 episodes of heterosexual mating were recorded during the same period, which means that 9 percent of all sexual activity was homosexual—a significant percentage when compared to other species.52 Similarly, investigators studying lesbian pairs in Western Gulls state, “We have estimated female-female pairs make up
It is also important to consider the behavioral type and context when evaluating frequency. Homosexual copulations in Tree Swallows, for example, have been characterized as “exceedingly rare” because they have been observed only infrequently and are much less common than heterosexual matings between pair-bonded birds. However, homosexual copulations are nonmonogamous matings (i.e., they typically involve birds that are not paired to one another and may even have heterosexual mates); it is insufficient in this case to compare the frequency rates of
Many scientists, on first observing an episode of homosexual activity, are also quick to classify the behavior as an exceptional or isolated occurrence for that species. In contrast, a single observed instance of heterosexuality is routinely interpreted as representative of a recurrent behavior pattern, even though it may occur (or be observed) extremely rarely or exhibit wide variation in form or context. This sets up a double standard in assessing and interpreting the prevalence of each behavior type, especially since opposite-sex mating can be a less than ubiquitous or uniform feature of an animal’s social life (see chapter 5). It also conflicts with the patterns established for other species. In repeated instances, homosexual activity was initially recorded in only one episode, dyad, or population (and usually interpreted—or dismissed—as an isolated example), but was then confirmed by subsequent research as a regular feature of the behavioral repertoire of the species—often spanning many decades, geographic areas, and behavioral contexts. 55 It is no longer possible to claim that homosexuality is an anomalous occurrence in a certain species simply because it has only been observed a handful of times.
In some cases, conflicting verbal assessments of the prevalence of homosexual activity are offered by the same investigators, when the actual quantitative data show a relatively high occurrence. Homosexual courtship/copulation in Pukeko, for example, is described as being both “common” and “relatively rare”—the actual