Science, Society, and Homosexuality

In 1965, astrophysicist and gay rights activist Frank Kameny declared that “research has had its day!” (Kameny, 1965, as cited in Rosario, 2002, p. 144). The medical establishment then held that homosexuality was a mental illness, a progressive model that had supplanted homosexuality as a sin (Hyde, DeLamater, & Byers, 2009). Yet in The Myth of Mental Illness (1960), psychiatrist Szasz cogently argued that conceptualising deviant behaviour as “mental illness” was a method of social control that had essentially taken over from moral policing by religious institutions. Despite its erudite reputation, Szasz argued that the science of homosexuality was unequivocally a reflection of society’s antihomosexual ethos, and a method of social repression (Rosario, 2002).

In decades prior to the 1960s, homosexuals had collaborated with scientists, hoping to show homosexuality as a natural imperative, and not an immoral choice (Rosario, 2002). Despite instructive experiments challenging scientific mores (Hooker, 1957), homosexuality continued to be pathologised into the 1960s (Gillespie, Pasche, Francis, & Wiedman, 1964). Impatient with an obtuse profession, the gay rights activists of the 1960s moved to confront the scientific establishment directly (Rosario). Inspired by an atmosphere of vocal civil rights movements, gay rights activists publicly took ownership of their sexual identity, declaring their opponents “both factually and morally wrong.” (Kameny, 1965, as cited in Rosario, 2002, p. 144).

As a political and moral force, gay rights activists precipitated a sweeping shift in scientific opinion, leading experts to conclude that homosexuality was not a clinical condition (Hegarty 2009; Rosario, 2002). Likewise, they left a transformational mark upon society which would come to adopt a biological essentialist theory of homosexuality (Hyde et al., 2009). In a culture that cherishes authenticity, a biological theory of homosexuality is a potent meme in challenging enduring discrimination (Bohan, 1996; Hyde et al., 2009). For example, a 2004 poll showed that 74% of Canadians believed that homosexuals should have the same rights as heterosexuals, despite the continuance of widespread oppressive homonegativity (Hyde et al., 2009). Biological explanations alone, however, provide an overly simplistic view of sexual identity, and disregard cognitive, volitional and sociological factors (Bohan, 1996; Hyde et al., 2009).

There is, however, a preponderance of evidence for biological factors in the development of sexual identity. Homosexuality has been linked to blood type and Rhesus factor (Ellis, Ficek, Burke, & Das, 2008), as well as genes on the 7th, 8th and 10th chromosomes (Hyde et al., 2009). Other evidence links male homosexuality to genes on the X chromosome that affect female fecundity (Iemmola & Ciani, 2009), offering a possible explanation to how genetic factors for homosexuality could evolve and persist.

Twin studies provide strong evidence for the role of genetics, but also for the role of other factors as well. A well known study by Bailey & Pillard (1991) found that lesbian and gay identity had a concordance rate close to 50% in monozygotic twins, far less than the 100% required for an entirely genetic explanation of homosexuality. The concordance rate was 22% for gay dizygotic twins, but only 9% for non-twin brothers, despite dizygotic twins and non-twin brothers having equal genetic similarity. The differences in these concordance rates indicate that environmental similarity has some effect on the formation of sexual identity.

Prenatal factors have also been implicated in the development of sexual orientation. For example, fetal exposure to high levels of androgens or estrogens show modest correlations to bisexual or homosexual orientation in women (Hyde et al., 2009; Meyer-Bahlburg, Dolezal, Baker, & New, 2008). A mother’s antibodies may also destroy important chemical messengers produced by the Y chromosome, which are involved in the sexual differentiation of male fetuses (Hyde et al., 2009). This is thought to account for the fraternal birth order effect, a cross-cultural phenomenon where having older brothers increases the likelihood of homosexuality in right-handed males (Blanchard, & Lippa, 2008; Hyde et al., 2009). Interestingly, despite the fraternal birth order effect, both male and female LGBs are more likely to be non-right-handed (Hyde et al., 2009).

Although biological theories enjoy popular support, psychologists recognise the importance of culture in shaping the development of sexual identity (Patterson, 2008). Mothers almost always assume that their infants are heterosexual, and inculcate heteronormativity through parental interaction that makes LGBs invisible (Martin, 2009). As young as 7, children begin to experiment with heterosexual scripts, which grow increasingly elaborate with age (Martin, 2009). Children are involved in complex heterosexual scripts as well as homophobic harassment by early adolescence (Martin, 2009; Renold 2002) – a time during which awareness of same-sex attraction generally occurs (Bohan, 1996).

The movement to a LGB identity involves stripping negative connotations from gay and lesbian social categories, a process known as detypification (Bohan, 1996). An individual may adopt an exclusively gay or lesbian identity, or change their identity to bisexual or heterosexual (Hyde et al., 2009). An 18 month study of 994 Canadian male homosexuals found that 10% had changed their identity from bisexual to gay or vice-versa (Engler et al., 2005). Women’s sexual identities are believed to be even more fluid (Bohan, 1997; Hyde et al., 2009), challenging the popular theory of sexual orientation as a stable characteristic.

Other popular theories have also been investigated and challenged by scientists. For example, the seduction and recruitment theory holds that children or teens are inducted into a homosexual lifestyle through seduction and recruitment by adult LGBs. However, there is no evidence for sexual molestation causing homosexuality, and most gays and lesbians do not engage in same-sex behaviour until well after becoming aware of their same-sex attraction (Bohan, 1997).

Psychodynamic theories fare no better. Freud posited that homosexuality arises as a developmental disturbance that can be cured with psychoanalysis (Gillespie et al., 1964). However, empirical evidence fails to support Freud’s developmental model (Bohan, 1997), and homosexuality as a disorder has been discredited (Hooker, 1957; Hyde et al., 2009). Furthermore, there is no evidence that sexual orientation can be changed by conversion therapies, despite more than a century of research (Hyde et al., 2009).

The civil rights movements of the 1960s radically changed social mores regarding minority sexual identities, however, many people still view homosexuality as a social problem (Sheldon, Pfeffer, Jayaratne, Feldbaum, & Petty, 2007). Homophobic individuals are more likely to be religious, score high in authoritarianism (Verweij et al., 2008), and view homosexuality as a life-choice (Sheldon et al., 2007). It seems, therefore, that scientific evidence for homosexuality as a natural imperative helps to marginalise the political opponents of the gay rights movement. Reducing homosexuality to biology, however, fails to challenge pervasive heteronormativity. Despite a societal shift towards a biological essentialist theory of homosexality, LGB activists continue to fight for legal equality, and suffer the significant emotional challenges of anti-gay prejudice and heterosexism (Hyde et al., 2009).

In instigating social change, the gay rights activists of the 1960s rejected science, and challenged society on moral grounds. Today, science is more sympathetic towards those social movements, and interest in the development of sexual identity has “never been greater” (Patterson, 2008, p. 1). However, the popularity of research into biological theories of homosexuality may derive in part from an overly simplistic cultural belief in the innate and stable nature of sexual identity. A biological explanation for minority sexual identities has aided LGBs politically, but failed to remove the stigma of the gay lifestyle or affirm LGB identities. The emancipation of LGBs may require a new cultural revolution, which in turn has the possibility of expediting a deeper understanding of human sexuality.


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© 2010, Aaron Michaux