Nature vs. Nurture Debates Over Sexuality

Are people born straight, gay, lesbian, bisexual or transgender? It’s a question that often invokes a “that’s above my pay grade” response from many academics, researchers, politicians and the like. But the debate over nature vs. nurture in regards to sexuality and sexual orientation has played an important role in the struggle for civil rights for LGBT people, with science becoming increasingly closer to recognizing that genetics play a significant role in determining one’s sexual orientation.

At its most basic level, the debate over nature vs. nurture concerns whether physical and behavioral traits are determined by an individual’s genetics (nature), or are determined by personal experiences (nurture). The nurture debate harkens back to the Aristotlean concept of tabula rosa, which suggests that personality and behavioral traits are entirely learned. In other words, all individuals start off in this world as blank slates in terms of their personality.

Nature debates over sexuality center around a person’s sexual orientation being decided by heredity and genes. As the American Psychological Association has noted, “Research suggests that the homosexual orientation is in place very early in the life cycle, possibly even before birth. It is found in about ten percent of the population, a figure which is surprisingly constant across cultures, irrespective of the different moral values and standards of a particular culture.” Studies conducted on the subject of homosexuality have focused on a range of possible genetic factors to link biological and hormonal factors to sexual orientation, from the size of one’s finger lengths, to fraternal birth order, to the number of ridges on one’s fingertips, to under-exposure (for gay men) or over-exposure (for lesbians) of prenatal androgens, among many others.

Some of the most cited studies have been conducted on twins – both those that were raised in the same household, and those who were separated at birth and raised in different families. Among both populations, researchers have found ample evidence to suggest a biological connection to homosexuality, particularly among identical twins separated at birth. In these cases, when one identical twin identified as gay, the other identical twin also identified as gay more than 50 percent of the time – despite being raised in a completely separate environment.

These studies, for the most part, have applied exclusively to gay men and not lesbians. However, subsequent research comparing brain shapes has linked lesbians and heterosexual men, as well as gay men and heterosexual women, adding yet another study to support a “nature” argument for homosexuality.

Nurture proponents, which have typically included populations that view homosexuality as aberrant or sinful (though not always), have rejected any sole biological influence for homosexuality, and suggest that one’s sexual orientation is an individual choice and/or is caused by environmental factors dictated after birth. Reasons given by nurture proponents for homosexuality have been as varied as estranged relationships between gay children and their parents, to allowing male children to play with dolls, to not forming healthy same-sex bonds with peers as a toddler, to sexual abuse at a young age, to name a few. Nurture proponents often see sexuality as something that can be changed, altered or suppressed, which has led to a number of gay rehabilitation programs. These programs, mostly run by religious organizations, paint same-sex attractions as unwanted and often suggest that individuals can control their sexuality through prayer or biblical resolution. Science, to a large extent, has debunked most ex-gay therapy programs and has noted the devastating tolls these programs take on LGBT individuals.

Many others believe that homosexuality is caused by a combination of biological, hormonal and environmental factors, merging the nature vs. nurture debate into one argument. Others believe in a sexuality scale, like the one championed by Alfred Kinsey, that suggest a person’s sexual history or sexual identity may fluctuate along a continuum between exclusively homosexual and exclusively heterosexual, and can be influenced by both environmental and biological factors.

Increasingly, however, the nature side of the debate is winning out in scientific circles. But as scientific evidence points more and more toward a biological or hormonal cause for homosexuality, concern over efforts to “cure” any biological or hormonal cause of homosexuality have surfaced. In his article, “Sexual Reorientation: The Gay Culture War is About to Turn Chemical,” William Saletan notes that with increasing scientific evidence that sexual orientation develops before birth, many who were once in the nurture camp are condoning efforts to find ways to alter the genetic, hormonal and biological factors that might determine one’s sexuality.

Saletan quotes Rev. Albert Mohler Jr., President of the Southern Baptist Theological Seminary, who says, “If a biological basis is found [for homosexuality], and if a prenatal test is then developed, and if a successful treatment to reverse the sexual orientation to heterosexual is ever developed, we would support its use.” Saletan also quotes Rev. Joseph Fessio, editor of Ignatius Press (Pope Benedict XVI’s English publisher), who says that because homosexuality is seen as a disorder within the Catholic Church, the Church would look favorably upon efforts to modify any neurobiological factor that results in homosexuality.

In the short-term, however, increasing scientific evidence supporting a nature argument for homosexuality has helped redirect the debate over whether one’s sexuality is a lifestyle choice or a personal orientation. This paradigm shift, according to researchers, could have a major impact in combating negative perceptions of homosexuality. What remains to be seen, however, is whether the neurobiological explanations for homosexuality will lead to opponents pushing for ways to use science to overturn one’s sexuality. And that could have massive, and very dangerous, ramifications for children and LGBT people.