Most Are Straight, Some Are Gay, and Why It Is That Way: The Science and Future of Sexual Orientation

This essay is co-published by <www.RespectfulConversations.net>, 2015

Should same-sex marriages “be recognized by the law as valid, with the same rights as traditional marriages?” In 2015, a record 60 percent of Americans told Gallup yes; only 37 percent said no. This flip from the 37/59 percent split a decade earlier (and from the 27/68 percent split of 1996), represents an astonishing transformation of public opinion. This momentum of gay support will likely continue as gay friends and relatives continue coming out, and as attitudes follow behavior (with same-sex marriage now the law of the land).

Equally striking is an enormous generation gap. Averaging across surveys, support for same-sex marriage runs about 40 percent among Americans over age 65 and nearly 80 percent among those ages 18 to 29. I am unaware of another social issue about which older and younger Americans so dramatically disagree. Today’s millennials and their grandparents live in different social worlds. Together with changing public opinion, the generation gap is forging a new social reality. Generational succession is destiny.

And should “homosexuals . . . have equal rights in terms of job opportunities?” From 1978 to 2008, the number telling Gallup yes skyrocketed from 56 to 89 percent.

Whatever our own opinions, perhaps we Christians can agree on two things:

  1. Our teaching of sexual ethics should not simply follow cultural trends. Rather than put our finger to the wind, we should put our nose to the Bible, aided by scholars who can help us discern its wisdom for our time.
  2. Public opinion surveys are like a car’s speedometer—they don’t drive the car, but do tell us how fast we (and the traffic around us) are moving. Today’s cultural traffic motivates our stepping back to understand what science has discerned about sexual orientation, and also to reengage biblical wisdom pertinent to human sexuality.

Sexual Orientation: The Numbers

European and American surveys, administered to random samples and with anonymity protected, indicate that about 3 to 4 percent of men and 2 percent of women report exclusively same-sex attractions. To explore sexual identity, Gallup asked 121,290 Americans: “Do you, personally, identify as lesbian, gay, bisexual, or transgender?” Yes, answered 3.4 percent. (For detailed citations regarding these and other findings in this essay, see my Psychology, 11th Edition, Worth Publishers.)

Does disapproval of homosexuality decrease it? On Facebook, the percent of men who publicly express a same-sex preference is 3 percent in tolerant California and 1 percent in disapproving Mississippi. Yet our culture’s increasing acceptance of same-sex relationships has not been accompanied by a notable change in the proportion of straight and gay people.

And consider this: conservative, religious Southern states generate more than average Google searches for sexually explicit content such as “gay sex” or answers to “Is my husband gay?” (MacInnis & Hodson; Stephens-Davidowitz). The number of Craigslist ads by men seeking “casual encounters” with other men is likewise at least as large in less tolerant states as in more tolerant states. And in African countries, where same-sex relationships are generally illegal, the gay–lesbian prevalence “is no different from other countries in the rest of the world,” reports the Academy of Science of South Africa. The bottom line: Whether a culture (or church or school) condemns or accepts same-sex unions, heterosexuality prevails and homosexuality exists.

Sexual Orientation Is a Natural Disposition

Multiple lines of research converge in indicating that our sexual orientation is something we do not choose and, especially so for men, cannot change.

Postnatal environmental influences are unknown. Sexual orientation has no known environment influences. Contrary to what Freudians and kindred reparative therapists have assumed, same-sex attractions appear not to be the result of child abuse or molestation, or a distant father and domineering mother. If distant fathers engendered gay sons, then shouldn’t boys growing up in father-absent homes (and in modern times with more absentee dads) be more often gay? (They are not.)

Having followed this research closely for several decades as a reporter of psychological science, what advice could I give to a young couple wondering how they can shape their newborn’s sexual orientation? My simple answer: I haven’t a clue. In the biggest behavior genetic study, the home environment’s association with sexual orientation was zero. So let us “judge not” parents for the sexual orientation of their children. And let us love our children as they are.

Same-sex attractions are displayed by many animal species. A first clue that sexual orientation is, instead, a natural, biological phenomenon comes from the several hundred species in which same-sex sexuality has been observed—from gorillas to grizzlies, from flamingos to owls. Among sheep, some 8 percent of rams shun ewes and seek to mount other males. Homosexuality, like heterosexuality, is part of the natural world.

Gay brains and straight brains. Neuroscientists have discovered several gay–straight brain differences. One, observed in post-mortem hypothalamus tissue, made people wonder: Does this brain difference help explain sexual orientation? Or do people’s sexual experiences leave fingerprints in their brains? Further research suggests that the brain difference is more cause than effect. It appears very early in life, and it is present in those male sheep that display same- versus other-sex attraction.

Male and female brains, and gay and straight brains, also respond selectively and automatically to various sexual stimuli, including sex-related scents. Thus, surmises researcher Simon LeVay, “Gay men simply don’t have the brain cells to be attracted to women” (121).

Genetics and sexual orientation. What causes the brain differences associated with sexual orientation? Is it genes? Prenatal influences? Or both? We’re not formed just by our genes. Genes get expressed in environments, rather like a tea bag expressing its flavor in hot water. But genes matter. Although not inherited in the straightforward way of eye color, twin and family studies confirm that sexual orientation is influenced by genes—many genes having small effects. One recent genomic study of 409 pairs of gay brothers identified sexual orientation links with parts of two chromosomes, one maternally transmitted.

But why, given that same-sex couples do not naturally reproduce, would “gay genes” exist in the human gene pool? Several studies have found that 1) homosexual men tend to have more homosexual relatives on their mother’s than on their father’s side, and 2) their heterosexual maternal relatives tend to produce more offspring than do the maternal relatives of heterosexual men. Perhaps, then, suggests a “fertile females theory,” the genes that dispose women to be strongly attracted (or attractive) to men—and to have more children—also dispose some men to be attracted to men. Thus, there may actually be reproductive wisdom to genes that dispose some men to love other men.

Prenatal influences. Experiments with some animals, including sheep, reveal that prenatal hormone exposure can alter postnatal gender traits and sexual orientation. In humans, prenatal sex hormones during the second to fifth month control the brain’s sexual differentiation. Female fetuses most exposed to testosterone, and male fetuses least exposed, appear most likely to later display gender atypical traits and same-sex attractions.

And here’s a repeated who-would-have-guessed finding: Men who have biological older brothers are more likely to be gay—about a third more likely for each additional older brother. Researcher Ray Blanchard and his colleagues speculate that the maternal immune system may be responding defensively to substances produced by male fetuses—with antibodies that affect the developing brain.

Gay–straight trait differences. These biological factors combine to also produce a number of gay–straight trait differences in things ranging from spatial abilities and fingerprint ridges to non-right-handedness, gender nonconformity, and occupational preferences. An example: Although men and women have equal overall intelligence, they differ, on average, in a few specific abilities. Straight men tend to be more skilled than straight women at mentally rotating objects. Gays’ and lesbians’ skills are intermediate. Such trait differences—part of the complex reality of sexual orientation—are not moral choices.

Sexual Orientation Is Enduring

We have all heard claims of people who, thanks to therapy or an ex-gay ministry, are said to have done a sexual U-turn, from actively gay to happily straight and married. And we have all heard stories of gay people who, hearing such stories, have sought change—only to end up depressed, suicidal, or in broken marriages.

Leading mental health associations—psychiatry, psychology, social work, pediatrics—have cautioned against sexual reorientation therapy. “Efforts to change sexual orientation are unlikely to be successful and involve some risk of harm,” declared the American Psychological Association’s governing body in a 125-to-4 vote.

Moreover, there is a growing list of ex-gay ministry leaders who have recanted their testimonies—the so-called “ex-ex-gays.” The best-known ex-gay poster person (including a Newsweek cover) was John Paulk. Once the manager of Focus on the Family’s Homosexuality and Gender Division, and board chair of Exodus (the umbrella organization of ex-gay ministries), Paulk, now an ex-ex-gay, says, “Today, I do not consider myself ‘ex-gay.’ . . . I do not believe that reparative therapy changes sexual orientation; in fact, it does great harm to many people.”

After twenty-two years with the ex-gay ministry Love in Action, and eleven years on the Exodus board, John Smid reported, “I’ve never met a man who experienced a change from homosexual to heterosexual.”

The British evangelical organization, Courage, once aimed to assist those struggling with “the clear biblical prohibition of homosexual practice.” No longer. Acknowledging the harm done by its fruitless sexual-reorientation efforts, Courage (now evolved to <www.two23.net>) became a place for “gay and lesbian Christians who are seeking a safe place of friendship in which to reconcile their faith and sexuality.”

In 2013, Exodus shut down, its long-time leader, Alan Chambers, declaring:

I am sorry for the pain and hurt that many of you have experienced. I am sorry some of you spent years working through the shame and guilt when your attractions didn’t change. I am sorry we promoted sexual orientation change efforts and reparative theories about sexual orientation that stigmatized parents. . . . More than anything, I am sorry that so many have interpreted this religious rejection by Christians as God’s rejection. I am profoundly sorry that many have walked away from their faith and that some have chosen to end their lives.

This sad history brings to mind Reinhold Niebuhr’s Serenity Prayer: “O God, give us grace to accept with serenity the things that cannot be changed, courage to change the things which should be changed, and the wisdom to distinguish the one from the other.”

Reformed and Ever-Reforming

If these are the facts, what then, as Christians, should be our response?

Those who aim to worship God with their minds will surely wish to attend both to natural revelation (as we explore God’s “fearfully and wonderfully made” human nature) and to biblical revelation.

Scholars are having a vigorous debate over biblical wisdom regarding same sex partnerships, much as earlier generations of biblical scholars debated anti-Semitism (in the pre-Holocaust years), interracial marriage, and women’s ordination.

Among the Bible’s 31,103 verses, only seven explicitly mention same-sex behaviors (and none of those discuss same-sex covenant partnerships). That leaves scholars to interpret scripture’s moral wisdom, based also on what else it has to say about marriage and human relationships.

Arguing for the traditionalist position, Robert Gagnon explores The Bible and Homosexual Practice; Kevin DeYoung asks What Does the Bible Really Teach about Homosexuality?; and my respected psychologist colleagues Stanton Jones and Mark Yarhouse include biblical wisdom in their discussion of Homosexuality: The Use of Scientific Research in the Church’s Moral Debate.

A newer Reformed-evangelical perspective argues that the church has, once again, misread the Bible, which actually supports a consistent sexual ethic for gay and straight people. Recent books include Jack Rogers’ Jesus, the Bible, and Homosexuality: Explode the Myths, Heal the Church; James Brownson’s Bible, Gender, Sexuality: Reframing the Church’s Debate on Same-Sex Relationships; William Stacey Johnson’s A Time to Embrace: Same-Gender Relationships in Religion, Law, and Politics; Mark Achtemeier’s The Bible’s Yes to Same-Sex Marriage: An Evangelical’s Change of Heart; Ken Wilson’s A Letter to My Congregation; and David Gushee’s Changing our Mind.

Ergo, this much seems true: Without echoing the culture’s increasing acceptance of recreational sex, faithful Christians are reassessing and discussing the Bible’s moral wisdom about covenant, same-sex partnerships. They are debating if there should be a single sexual ethic for all, gay and straight, or a different ethic for those naturally disposed to love someone of their own sex.

For those who embrace a “Reformed and ever-reforming” faith tradition—one that esteems a spirit of humility and is open to the continuing work of the Spirit—this fresh look at scripture is how it should be. And so it has been across time, as people of faith have changed their minds about marriage—from practicing arranged marriages to favoring romantic choice; from assuming polygyny to mandating monogamy; from viewing marriage as inferior to celibacy to seeing it as an equal calling; from assuming male headship to preferring mutuality; from shunning interracial marriage to welcoming it; from disciplining divorced people to welcoming them into our faith communities. In each case, our religious ancestors found proof texts to support their cultural assumptions.

So, What Should Christians Do?

In a 2015 survey, Gallup found that two-thirds of Americans now regard “sex between an unmarried man and woman” as “morally acceptable.” Six in ten say the same about “having a baby outside marriage.” In a University of Michigan survey of American high school students, two thirds agreed that “It is usually a good idea for a couple to live together before they get married in order to find out whether they really get along.” Only about one-third agreed that “Most people will have fuller and happier lives if they choose legal marriage rather than staying single or just living with someone.”

But we have massive evidence indicating that

  • humans do live fuller and happier (and healthier) lives if married,
  • children fare better in households with married parents (even after controlling for income and race), and
  • communities with high marriage rates experience less crime, educational dropout, and poverty.

These findings fit well with what we have learned about the human “need to belong.” We are social animals. We—all of us, whether gay or straight—flourish when deeply connected with others in close, enduring, mutually supportive relationships. We were not made to be alone.

Having shared the facts as I see them, might I be granted permission to venture a conclusion—one I offered in A Friendly Letter to Skeptics and Atheists (78, 81)? Should we, as Christians and Christian educators, put on our social radar screens the concerns that Jesus had on his? What would Jesus do? Rather than tie “onto people’s backs loads that are heavy and hard to carry,” as Jesus said of the Pharisees, why not offer a positive affirmation of monogamy? Why not stand up for healthy relationships that satisfy the human need to belong within covenant partnerships? Rather than advocating a sexual double standard for straight people (marry or be celibate) and gay people (sorry, you must be celibate), why not proclaim a single Christian sexual ethic? Why not yoke sex with faithfulness? Why not seal love with commitment? Why not foster a conservative, marriage-supporting positive argument: that the world would be a happier and healthier place if, for all people, sex, love, and marriage routinely went together? . . .

Those of us who support an inclusive pro-monogamy norm can take heart that more and more people see the welcoming of gay people into monogamy—into marriage—as a positive trend while also seeing declines in teen pregnancy and increases in teen abstinence as positive trends. Marriage nevertheless is in trouble. With the marriage rate having declined, with most first marriages preceded by cohabitation, with 39 percent of American children in 2006 born outside of marriage, and with pornography a bigger business than professional football, there is surely a need to refocus on the family. Alas, rather than focus on getting and keeping people married, the church is diverting its energy into keeping gay people unmarried. One is reminded of senior devil Screwtape’s advice (in C. S. Lewis’ Screwtape Letters) on how to corrupt: “The game is to have them all running about with fire extinguishers whenever there is a flood.”


Works Cited

Chambers, Alan. “Exodus Int’l President to the Gay Community: ‘We’re Sorry.’” Alan Chambers. Web. Accessed 25 June 2015. <alanchambers.org/exodus-intl-president-to-the-gay-community-were-sorry>

“Diversity in Human Sexuality: Implications for Policy in Africa.” Academy of Science of South Africa, May 2015: 36. Web. Accessed 23 June 2015. <www.assaf.org.za>

LeVay, Simon. The Sexual Brain. Cambridge, MA: MIT Press, 1993.

MacInnis, Cara C., and Gordon Hodson. “Do American States with More Religious or Conservative Populations Search More for Sexual Content on Google?” Archives of Sexual Behavior 44 (2015): 137–47. Print.

Myers, David. A Friendly Letter to Skeptics and Atheists. San Francisco: Jossey-Bass, 2008.

Paulk, John. Quoted by Steffan, Melissa. “Former Ex-Gay Spokesman John Paulk Apologizes Amid Divorce.” Christianity Today: Gleanings. Posted 2 May 2013. Web. Accessed 25 June 2015. <www.christianitytoday.com/gleanings/2013/may/former-ex-gay-spokesman-john-paulk-apologizes-amid-divorce.html>

Smid, John. “Where Is the Repentance?” Grace Rivers. Posted 7 Oct. 2011. Web. Accessed 25 June 2015. <www.gracerivers.com/gays-repent/>

Stephens-Davidowitz, Seth. “How Many American Men are Gay?” New York Times 7 December 2013: SR5. Web.


David Myers serves as professor of psychology at Hope College in Holland, Michigan.