Is Homosexuality a Darwinian Paradox?

MANY SOCIAL SCIENTISTS BELIEVE that homosexuality is a social construction.They contend that homosexuality is not a biological given (a “natural kind”) but rather the contingent product of social and psychological interactions—a product that may have been designed to fulfill certain ideological needs. Most evolutionary psychologists, on the other hand, hold that homosexuality is a naturally selected adaptation, or at least a trade-off for such an adaptation.These views seem to be diametrically opposed. Of course, the dispute between social constructivism and evolutionary psychology is not limited to the issue of homosexuality. Social constructivists have criticized evolutionary psychology on many other grounds as well. Conversely, evolutionary biologists and evolutionary psychologists have been less than sympathetic to social constructivism, which they generally regard as a fickle ideology lacking scientific standards and, worse, priding itself in its almost nonsensical vocabulary (Kruger 2002). As Richard Dawkins (1995) quipped: “Show me a cultural relativist at thirty thousand feet and I’ll show you a hypocrite” (pp. 31–32). Only a small minority of scientists and philosophers seems to realize that such a polarization is not inevitable. David Sloan Wilson (2005) has argued in favor of an “evolutionary social constructivism,” claiming that the universality of human nature and the contingency of human culture need not be in conflict. According to Wilson, the potential for change—behavioral plasticity—is an essential part of our nature. Such exercises in bridge building are surely praiseworthy. Still, the value of evolutionary social constructivism depends on the extent to which it can fruitfully be applied to concrete phenomena, that is, on its ability to provide better explanations of specific phenomena than either traditional evolutionary or social constructivist approaches. Short of that, evolutionary social constructivism will amount to no more than a not-so-fancy name for the old multifactor model of human behavior (nature/genes and nurture/culture, instead of nature/genes versus nurture/culture). In order for evolutionary social constructivism to be viewed as a viable alternative to existing theories, it must show why and how human nature and human discourses interact the way they do. Human male homosexuality is an ideal test case for evolutionary social constructivism. Both sides have produced an equally vast amount of literature about it. The founding father of evolutionary psychology, E. O.Wilson (1975), devoted several pages of Sociobiology: The New Synthesis to homosexual behavior in humans. Ever since the publication of Sociobiology, it is nearly impossible to find a book on evolutionary psychology or behavioral ecology in which the author does not feel obliged at least to touch upon the theme of homosexuality. On the other hand, Michel Foucault (1978), generally regarded as the founder of social constructivism, has argued repeatedly for the profoundly constructivist origin of male homosexuality. The idea that there might be some truth in both options, evolutionary theory and social constructivism, is rarely entertained (Shakespeare and Erickson 2001). We believe, however, that both evolutionary theory and social constructivism have provided valuable insights into homosexuality, and that evolutionary social constructivism provides a framework for integrating them.This paper attempts just such an integration. We begin by explaining why evolutionary psychologists see homosexuality as a Darwinian paradox (or puzzle) and looking at how they have tried to solve this paradox.We then adopt a constructivist stance and argue that this so-called paradox is really not a paradox at all, because homosexuality as we now know it is not a natural kind but a social construction. Indeed, ethology and human history suggest that we should distinguish between same-sex sexual behavior, which has been displayed by numerous species throughout evolutionary history, and homosexuality, which refers to a relatively new, heterogeneous, and uniquely human complex of desires, behaviors, and identities. We discuss one particular Darwinian hypothesis, the alliance-formation hypothesis, that is able to reckon with this important distinction, and show how this hypothesis makes sense of some curious findings about both types of same-sex sexuality. Finally, we argue that the alliance-formation hypothesis can explain how a socially constructed homosexuality is embedded in our evolved nature.

Introducing the Paradox

Homosexuality is usually considered to be a Darwinian paradox or an evolutionary puzzle, since if there were such thing as a “gay gene,” evolutionary theory predicts its removal from a species’ gene pool (Berman 2003; CamperioCiani, Corna, and Claudio 2004).After all, is it not obvious that the reproductive success of homosexuals is much lower than the reproductive success of heterosexuals? The question, in short, is how can a gay gene spread through a population if its carriers do not reproduce? Neo-Darwinism has, over time, constructed a number of models to account for this apparent paradox. Most of the proposed solutions to this puzzle are based on inclusive fitness, or kin selection. Some authors, such as E. O.Wilson, have argued that homosexual behavior directly promotes the reproductive success of relatives: some men may “choose” to protect their close relatives, because these relatives share a significant number of genes with them. Inclusive fitness would thus enable the gay gene to proliferate through collateral lines of descent, even if its bearers did not reproduce at all. In this model, homosexuals would be “helpers at the nest.” The main challenge of the kin-selection hypothesis is to explain why an individual’s homosexuality would contribute to his relatives’ fitness. Theoretically, this is far from evident. As Trivers (1985) has noted, one should expect the helpers at the nest to be asexual—like the workers in eusocial species, such as ants and naked mole rats—rather than homosexual. Second, data on the actual behavior of contemporary male homosexuals indicate that they are not as prone to protect their close genetic cohort as Wilson suggests—at least they are no more likely than heterosexual men to channel resources toward family members (Bobrow and Bailey 2001). It may be premature to extrapolate this conclusion to homosexuals generally, or to assume that late 20th-century homosexuals are representative of men who have engaged in same-sex sexual behavior throughout history. However, premodern “homosexuals” probably did not spend their time assisting close kin either. Apart from some Siberian transvestite shamanhealers and perhaps a few other groups, there is no evidence that those preferring same-sex sexual activities have ever really enhanced their families’ reproductive fitness in a direct way (gifts, assistance, etc.; Murray 2000). Indeed, as we will argue below, most of them simply had their hands full with raising their own children. Wilson’s (1978) proposal, that the close relatives of homosexuals “would have more viable offspring as a result of their presence” (p. 144), is untenable. Another hypothesis is that homosexuality has been preserved by natural selection as a trade-off for another, adaptive trait, one that is somehow biologically connected to the supposed gay gene. What trait? Well, Italian researchers have recently reported that “female maternal relatives of homosexuals have higher fecundity than female maternal relatives of heterosexuals” (Camperio-Ciani, Corna, and Claudio 2004, p. 2217).These researchers also found that there are more homosexuals among a homosexual’s male maternal relatives than there are among a homosexual’s male paternal relatives (while there are no differences among the relatives of heterosexuals). They speculate that homosexuality is a trade-off for the enhanced fecundity of female maternal relatives of homosexuals. This hypothesis would account for the persistence of homosexuality and would support the conviction of several geneticists that homosexuality is inherited matrilineally. The finding about the enhanced fecundity of females in the maternal lines of homosexuals has not been confirmed, and the authors indicate that, if true, it would only account for a limited percentage of the genetic variance in male sexual orientation. Theoretically, though, the trade-off explanation of male homosexuality would still be attractive, provided we think of homosexuality as an evolutionary paradox. But is it, really?

Excerpts taken from

The Evolution of a Social Construction: The Case of Male Homosexuality

Pieter R. Adriaens* and Andreas De Block*??

*Institute of Philosophy, University of Leuven, Belgium. ?Faculty of Philosophy, Radboud University, Nijmegen,The Netherlands. Correspondence: Pieter R. Adriaens, Institute of Philosophy, University of Leuven, Kardinaal Mercierplein 2, B-3000 Leuven, Belgium. E-mail: [email protected]. The authors thank Siegfried Dewitte, David Sloan Wilson, and an anonymous referee for their helpful and inspiring comments.This work was supported by the Research Foundation-Flanders (FWOVlaanderen; P.A.) and the Dutch Organisation for Scientific Research (NWO;A. De B.) Perspectives in Biology and Medicine, volume 49, number 4 (autumn 2006):570–85 ? 2006 by The Johns Hopkins University Press