5.1 Understanding Sexual Orientation

Learning Objectives

  1. Define sexual orientation and gender identity.
  2. Describe what percentage of the US population is estimated to be LGBT.
  3. Summarize the history of sexual orientation.
  4. Evaluate the possible reasons for sexual orientation.

Sexual orientation refers to a person’s preference for sexual relationships with individuals of the other sex (heterosexuality), one’s own sex (homosexuality), or both sexes (bisexuality). The term also increasingly refers to transgender (also transgendered) individuals, those whose behavior, appearance, and/or gender identity (the personal conception of oneself as female, male, both, or neither) departs from conventional norms. Transgendered individuals include transvestites (those who dress in the clothing of the opposite sex) and transsexuals (those whose gender identity differs from their physiological sex and who sometimes undergo a sex change). A transgender woman is a person who was born biologically as a male and becomes a woman, while a transgender man is a person who was born biologically as a woman and becomes a man. As you almost certainly know, gay is the common term now used for any homosexual individual; gay men or gays is the common term used for homosexual men, while lesbian is the common term used for homosexual women. All the types of social orientation just outlined are often collectively referred to by the shorthand LGBT (lesbian/gay/bisexual/transgender). As you almost certainly also know, the term straight is used today as a synonym for heterosexual.

Counting Sexual Orientation

We will probably never know precisely how many people are gay, lesbian, bisexual, or transgendered. One problem is conceptual. For example, what does it mean to be gay or lesbian? Does one need to actually have sexual relations with a same-sex partner to be considered gay? What if someone is attracted to same-sex partners but does not actually engage in sex with such persons? What if someone identifies as heterosexual but engages in homosexual sex for money (as in certain forms of prostitution) or for power and influence (as in much prison sex)? These conceptual problems make it difficult to determine the extent of homosexuality (Gates, 2011).

A gay couple watching a parade.

It is difficult for several reasons to know exactly how many people are LGBT.

A second problem is empirical. Even if we can settle on a definition of homosexuality, how do we then determine how many people fit this definition? For better or worse, our best evidence of the number of gays and lesbians in the United States comes from surveys that ask random samples of Americans various questions about their sexuality. Although these are anonymous surveys, some individuals may be reluctant to disclose their sexual activity and thoughts to an interviewer. Still, scholars think that estimates from these surveys are fairly accurate but also that they probably underestimate by at least a small amount the number of gays and lesbians.

During the 1940s and 1950s, sex researcher Alfred C. Kinsey carried out the first notable attempt to estimate the number of gays and lesbians (Kinsey, Pomeroy, & Martin, 1948; Kinsey, Pomeroy, Martin, & Gebhard, 1953). His project interviewed more than 11,000 white women and men about their sexual experiences, thoughts, and attractions, with each subject answering hundreds of questions. While most individuals had experiences and feelings that were exclusively heterosexual, a significant number had experiences and feelings that were either exclusively homosexual or both heterosexual and homosexual in varying degrees. These findings led Kinsey to reject the popular idea back then that a person is necessarily either heterosexual or homosexual (or straight or gay, to use the common modern terms). As he wrote, “It is a characteristic of the human mind that tries to dichotomize in its classification of phenomena…Sexual behavior is either normal or abnormal, socially acceptable or unacceptable, heterosexual or homosexual; and many persons do not want to believe that there are gradations in these matters from one to the other extreme” (Kinsey et al., 1953, p. 469). Perhaps Kinsey’s most significant and controversial finding was that gradations did, in fact, exist between being exclusively heterosexual on the one hand and exclusively homosexual on the other hand. To reflect these gradations, he developed the well-known Kinsey Scale, which ranks individuals on a continuum ranging from 0 (exclusively heterosexual) to 6 (exclusively homosexual).

In terms of specific numbers, Kinsey found that (a) 37 percent of males and 13 percent of females had had at least one same-sex experience; (b) 10 percent of males had mostly homosexual experiences between the ages of 16 and 55, while up to 6 percent of females had mostly homosexual experiences between the ages of 20 and 35; (c) 4 percent of males were exclusively homosexual after adolescence began, compared to 1–3 percent of females; and (d) 46 percent of males either had engaged in both heterosexual and homosexual experiences or had been attracted to persons of both sexes, compared to 14 percent of females.

A crazy fun loving lesbian couple

An estimated 3.8 percent of the US adult population identifies as LGBT. This figure amounts to about 9 million people.

More recent research updates Kinsey’s early findings and, more important, uses nationally representative samples of Americans (which Kinsey did not use). In general, this research suggests that Kinsey overstated the numbers of Americans who have had same-sex experiences and/or attractions. A widely cited survey carried out in the early 1990s by researchers at the University of Chicago found that 2.8 percent of men and 1.4 percent of women self-identified as gay/lesbian or bisexual, with greater percentages reporting having had sexual relations with same-sex partners or being attracted to same-sex persons (see Table 5.1 “Prevalence of Homosexuality in the United States”). In the 2010 General Social Survey (GSS), 1.8 percent of men and 3.3 percent of women self-identified as gay/lesbian or bisexual. In the 2006–2008 National Survey of Family Growth (NSFG) conducted by the federal government (Chandra, Mosher, Copen, & Sionean, 2011), 2.8 percent of men self-identified as gay or bisexual, compared to 4.6 percent of women (ages 18–44 for both sexes).

Table 5.1 Prevalence of Homosexuality in the United States

Activity, attraction, or identity Men (%) Women (%)
Find same-sex sexual relations appealing 4.5 5.6
Attracted to people of same sex 6.2 4.4
Identify as gay or bisexual 2.8 1.4
At least one sex partner of same sex during past year among those sexually active 2.7 1.3
At least one sex partner of same sex since turning 18 4.9 4.1

These are all a lot of numbers, but demographer Gary J. Gates (2011) drew on the most recent national survey evidence to come up with the following estimates for adults 18 and older:

  • 3.5 percent of Americans identify as gay, lesbian, or bisexual, and 0.3 percent are transgender; these figures add up to 3.8 percent of Americans, or 9 million people, who are LGBT.
  • 3.4 percent of women and 3.6 percent of men identify as LGB.
  • 66.7 percent of LGB women identify as bisexual, and 33.3 percent identify as lesbian; 33.3 percent of LGB men identify as bisexual, and 66.7 percent identify as gay. LGB women are thus twice as likely as LGB men to identify as bisexual.
  • 8.2 percent of Americans, or 19 million people, have engaged in same-sex sexual behavior, with women twice as likely as men to have done so.
  • 11 percent of Americans, or 25.6 million people, report having some same-sex sexual attraction, with women twice as likely as men to report such attraction.

The overall picture from these estimates is clear: Self-identified LGBT people comprise only a small percentage of the US population, but they amount to about 9 million adults and undoubtedly a significant number of adolescents. In addition, the total number of people who, regardless of their sexual orientation, have had a same-sex experience is probably at least 19 million, and the number who have had same-sex attraction is probably at least 25 million.

Sexual Orientation in Historical Perspective

Based on what is known about homosexuality in past societies, it should be no surprise that so many people in the United States identify as gay/lesbian or have had same-sex experiences. This historical record is clear: Homosexuality has existed since ancient times and in some societies has been rather common or at least fully accepted as a normal form of sexual expression.

In the great city of Athens in ancient Greece, male homosexuality (to be more precise, sexual relations between a man and a teenaged boy and, less often, between a man and a man) was not only approved but even encouraged. According to classical scholar K. J. Dover (1989, p. 12), Athenian society “certainly regarded strong homosexual desire and emotion as normal,” in part because it also generally “entertained a low opinion of the intellectual capacity and staying-power of women.” Louis Crompton (2003, p. 2), who wrote perhaps the definitive history of homosexuality, agrees that male homosexuality in ancient Greece was common and notes that “in Greek history and literature…the abundance of accounts of homosexual love overwhelms the investigator.” He adds,

Greek lyric poets sing of male love from almost the earliest fragments down to the end of classical times…Vase-painters portray scores of homoerotic scenes, hundreds of inscriptions celebrate the love of boys, and such affairs enter into the lives of a long catalogue of famous Greek statesmen, warriors, artists, and authors. Though it has often been assumed that the love of males was a fashion confined to a small intellectual elite during the age of Plato, in fact it was pervasive throughout all levels of Greek society and held an honored place in Greek culture for more than a thousand years, that is, from before 600 B.C.E. to about 400 C.E.

Male homosexuality in ancient Rome was also common and accepted as normal sexuality, but it took a different form from than in ancient Greece. Ancient Romans disapproved of sexual relations between a man and a freeborn male youth, but they approved of relations between a slave master and his youthful male slave. Sexual activity of this type was common. As Crompton (2003, p. 80) wryly notes, “Opportunities were ample for Roman masters” because slaves comprised about 40 percent of the population of ancient Rome. However, these “opportunities” are best regarded as violent domination by slave masters over their slaves.

By the time Rome fell in 476 CE, Europe had become a Christian continent. Influenced by several passages in the Bible that condemn homosexuality, Europeans considered homosexuality a sin, and their governments outlawed same-sex relations. If discovered, male homosexuals (or any men suspected of homosexuality) were vulnerable to execution for the next fourteen centuries, and many did lose their lives. During the Middle Ages, gay men and lesbians were stoned, burned at the stake, hanged, or beheaded, and otherwise abused and mistreated. Crompton (2003, p. 539) calls these atrocities a “routine of terror” and a “kaleidoscope of horrors.” Hitler’s persecution of gay men several centuries after the Middle Ages ended had ample precedent in European history.

In contrast to the European treatment of gay men and lesbians, China and Japan from ancient times onward viewed homosexuality much more positively in what Crompton (2003, p. 215) calls an “unselfconscious acceptance of same-sex relations.” He adds that male love in Japan during the 1500s was “a national tradition—one the Japanese thought natural and meritorious” (Crompton, 2003, p. 412) and very much part of the samurai (military nobility) culture of preindustrial Japan. In China, both male and female homosexuality were seen as normal and even healthy sexual outlets. Because Confucianism, the major Chinese religion when the Common Era began, considered women inferior, it considered male friendships very important and thus may have unwittingly promoted same-sex relations among men. Various artistic and written records indicate that male homosexuality was fairly common in China over the centuries, although the exact numbers can never be known. When China began trading and otherwise communicating with Europe during the Ming dynasty, its tolerance for homosexuality shocked and disgusted Catholic missionaries and other Europeans. Some European clergy and scientists even blamed earthquakes and other natural disasters in China on this tolerance.

In addition to this body of work by historians, anthropologists have also studied same-sex relations in small, traditional societies. In many of these societies, homosexuality is both common and accepted as normal sexual behavior. In one overview of seventy-six societies, the authors found that almost two-thirds regarded homosexuality as “normal and socially acceptable for certain members of the community” (Ford & Beach, 1951, p. 130). Among the Azande of East Africa, for example, young warriors live with each other and are not allowed to marry. During this time, they often have sex with younger boys. Among the Sambia of New Guinea, young males live separately from females and have same-sex relations for at least a decade. It is felt that the boys would be less masculine if they continued to live with their mothers and that the semen of older males helps young boys become strong and fierce (Edgerton, 1976).

This brief historical and anthropological overview provides ready evidence of what was said at its outset: Homosexuality has existed since ancient times and in some societies has been rather common or at least fully accepted as a normal form of sexual expression. Although Western society, influenced by the Judeo-Christian tradition, has largely condemned homosexuality since Western civilization began some 2,000 years ago, the great civilizations of ancient Greece and ancient China and Japan until the industrial age approved of homosexuality. In these civilizations, male homosexuality was fairly common, and female homosexuality was far from unknown. Same-sex relations are also fairly common in many of the societies that anthropologists have studied. Although Western societies have long considered homosexuality sinful and unnatural and more generally have viewed it very negatively, the historical and anthropological record demonstrates that same-sex relationships are far from rare. They thus must objectively be regarded as normal expressions of sexuality.

In fact, some of the most famous individuals in Western political, literary, and artistic history certainly or probably engaged in same-sex relations, either sometimes or exclusively: Alexander the Great, Hans Christian Andersen, Marie Antoinette, Aristotle, Sir Francis Bacon, James Baldwin, Leonard Bernstein, Lord Byron, Julius Caesar, Ralph Waldo Emerson, Frederick the Great, Leonardo de Vinci, Herman Melville, Michelangelo, Plato, Cole Porter, Richard the Lionhearted, Eleanor Roosevelt, Socrates, Gertrude Stein, Pyotr Tchaikovsky, Henry David Thoreau, Walt Whitman, Tennessee Williams, Oscar Wilde, and Virginia Woolf, to name just a few. Regardless or perhaps in some cases because of their sexuality, they all made great contributions to the societies in which they lived.

Explaining Sexual Orientation

We have seen that it is difficult to determine the number of people who are gay/lesbian or bisexual. It is even more difficult to determine why some people have these sexual orientations while most do not, and scholars disagree on the “causes” of sexual orientation (Engle, McFalls, Gallagher, & Curtis, 2006; Sheldon, Pfeffer, Jayaratne, Feldbaum, & Petty, 2007). Determining the origins of sexual orientation is not just an academic exercise. When people believe that the roots of homosexuality are biological or that gays otherwise do not choose to be gay, they are more likely to have positive or at least tolerant views of same-sex behavior. When they believe that homosexuality is instead merely a personal choice, they are more likely to disapprove of it (Sheldon et al., 2007). For this reason if for no other, it is important to know why some people are gay or bisexual while most are not.

Studies of the origins of sexual orientation focus mostly on biological factors and on social and cultural factors, and a healthy scholarly debate exists on the relative importance of these two sets of factors.

Biological Factors

Research points to certain genetic and other biological roots of sexual orientation but is by no means conclusive. One line of research concerns genetics. Although no “gay gene” has been discovered, studies of identical twins find they are more likely to have the same sexual orientation (gay or straight) than would be expected from chance alone (Kendler, Thornton, Gilman, & Kessler, 2000; Santtila et al., 2008). Because identical twins have the same DNA, this similarity suggests, but does not prove, a genetic basis for sexual orientation. Keep in mind, however, that any physical or behavioral trait that is totally due to genetics should show up in both twins or in neither twin. Because many identical twins do not have the same sexual orientation, this dissimilarity suggests that genetics are far from the only cause of sexual orientation, to the extent they cause it at all. Several methodological problems also cast doubt on findings from many of these twin studies. A recent review concluded that the case for a genetic cause of sexual orientation is far from proven: “Findings from genetic studies of homosexuality in humans have been confusing—contradictory at worst and tantalizing at best—with no clear, strong, compelling

A pregnant woman

Despite scholarly speculation, sexual orientation does not appear to be affected by the level of prenatal hormones.

Another line of research concerns brain anatomy, as some studies find differences in the size and structure of the hypothalamus, which controls many bodily functions, in the brains of gays versus the brains of straights (Allen & Gorski, 1992). However, other studies find no such differences (Lasco, Jordan, Edgar, Petito, & Byne, 2002). Complicating matters further, because sexual behavior can affect the hypothalamus (Breedlove, 1997), it is difficult to determine whether any differences that might be found reflect the influence of the hypothalamus on sexual orientation, or instead the influence of sexual orientation on the hypothalamus (Sheldon et al., 2007).

A third line of biological research concerns hormonal balance in the womb, with scientists speculating that the level of prenatal androgen affects which sexual orientation develops. Because prenatal androgen levels cannot be measured, studies typically measure it only indirectly in the bodies of gays and straights by comparing the lengths of certain fingers and bones that are thought to be related to prenatal androgen. Some of these studies suggest that gay men had lower levels of prenatal androgen than straight men and that lesbians had higher levels of prenatal androgen than straight women, but other studies find no evidence of this connection (Martin & Nguyen, 2004; Mustanski, Chivers, & Bailey, 2002). A recent review concluded that the results of the hormone studies are “often inconsistent” and that “the notion that non-heterosexual preferences may reflect [deviations from normal prenatal hormonal levels] is not supported by the available data” (Rahman, 2005, p. 1057).

Social and Cultural Factors

Sociologists usually emphasize the importance of socialization over biology for the learning of many forms of human behavior. In this view, humans are born with “blank slates” and thereafter shaped by their society and culture, and children are shaped by their parents, teachers, peers, and other aspects of their immediate social environment while they are growing up.

Given this standard sociological position, one might think that sociologists generally believe that people are gay or straight not because of their biology but because they learn to be gay or straight from their society, culture, and immediate social environment. This, in fact, was a common belief of sociologists about a generation ago (Engle et al., 2006). In a 1988 review article, two sociologists concluded that “evidence that homosexuality is a social construction [learned from society and culture] is far more powerful than the evidence for a widespread organic [biological] predisposition toward homosexual desire” (Risman & Schwartz, 1988, p. 143). The most popular introductory sociology text of the era similarly declared, “Many people, including some homosexuals, believe that gays and lesbians are simply ‘born that way.’ But since we know that even heterosexuals are not ‘born that way,’ this explanation seems unlikely…Homosexuality, like any other sexual behavior ranging from oral sex to sadomasochism to the pursuit of brunettes, is learned” (Robertson, 1987, p. 243).

However, sociologists’ views of the origins of sexual orientation have apparently changed since these passages were written. In a recent national survey of a random sample of sociologists, 22 percent said male homosexuality results from biological factors, 38 percent said it results from both biological and environmental (learning) factors, and 39 percent said it results from environmental factors (Engle et al., 2006). Thus 60 percent (= 22 + 38) thought that biology totally or partly explains male homosexuality, almost certainly a much higher figure than would have been found a generation ago had a similar survey been done.

In this regard, it is important to note that 77 percent (= 38 + 39) of the sociologists still feel that environmental factors, or socialization, matter as well. Scholars who hold this view believe that sexual orientation is partly or totally learned from one’s society, culture, and immediate social environment. In this way of thinking, we learn “messages” from all these influences about whether it is OK or not OK to be sexually attracted to someone from our own sex and/or to someone from the opposite sex. If we grow up with positive messages about same-sex attraction, we are more likely to acquire this attraction. If we grow up with negative messages about same-sex attraction, we are less likely to acquire it and more likely to have heterosexual desire.

It is difficult to do the necessary type of research to test whether socialization matters in this way, but the historical and cross-cultural evidence discussed earlier provides at least some support for this process. Homosexuality was generally accepted in ancient Greece, ancient China, and ancient Japan, and it also seemed rather common in those societies. The same connection holds true in many of the societies that anthropologists have studied. In contrast, homosexuality was condemned in Europe from the very early part of the first millennium CE, and it seems to have been rather rare (although it is very possible that many gays hid their sexual orientation for fear of persecution and death).

So where does this leave us? What are the origins of sexual orientation? The most honest answer is that we do not yet know its origins. As we have seen, many scholars attribute sexual orientation to still unknown biological factor(s) over which individuals have no control, just as individuals do not decide whether they are left-handed or right-handed. Supporting this view, many gays say they realized they were gay during adolescence, just as straights would say they realized they were straight during their own adolescence; moreover, evidence (from toy, play, and clothing preferences) of future sexual orientation even appears during childhood (Rieger, Linsenmeier, Bailey, & Gygax, 2008). Other scholars say that sexual orientation is at least partly influenced by cultural norms, so that individuals are more likely to identify as gay or straight and be attracted to their same sex or opposite sex depending on the cultural views of sexual orientation into which they are socialized as they grow up. At best, perhaps all we can say is that sexual orientation stems from a complex mix of biological and cultural factors that remain to be determined.

The official stance of the American Psychological Association (APA) is in line with this view. According to the APA, “There is no consensus among scientists about the exact reasons that an individual develops a heterosexual, bisexual, gay, or lesbian orientation. Although much research has examined the possible genetic, hormonal, developmental, social, and cultural influences on sexual orientation, no findings have emerged that permit scientists to conclude that sexual orientation is determined by any particular factor or factors. Many think that nature and nurture both play complex roles; most people experience little or no sense of choice about their sexual orientation” (American Psychological Association, 2008, p. 2).

Although the exact origins of sexual orientation remain unknown, the APA’s last statement is perhaps the most important conclusion from research on this issue: Most people experience little or no sense of choice about their sexual orientation. Because, as mentioned earlier, people are more likely to approve of or tolerate homosexuality when they believe it is not a choice, efforts to educate the public about this research conclusion should help the public become more accepting of LGBT behavior and individuals.

Key Takeaways

  • An estimated 3.8 percent, or 9 million, Americans identify as LGBT.
  • Homosexuality seems to have been fairly common and very much accepted in some ancient societies as well as in many societies studied by anthropologists.
  • Scholars continue to debate the extent to which sexual orientation stems more from biological factors or from social and cultural factors and the extent to which sexual orientation is a choice or not a choice.

For Your Review

  1. Do you think sexual orientation is a choice, or not? Explain your answer.
  2. Write an essay that describes how your middle school and high school friends talked about sexual orientation generally and homosexuality specifically.


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