What makes people gay, lesbian, bisexual, or heterosexual? And who cares? Written by one of the leading scientists in the research of sexual orientation, Queer Science looks at how scientific discoveries about homosexuality influence society's attitude toward gays and lesbians, beginning with the theories of the German sexologist and gay-rights pioneer Magnus Hirschfeld and culminating with the latest discoveries in brain science, genetics, endocrinology, and cognitive psychology.
Dr. Simon LeVay is a writer and lecturer with a background in neuroscience. He is best known for his research on the brain and sexuality, but has also spent many years studying the visual system. He has written or co-authored several books on sexuality, and coauthored books on such diverse topics as earthquakes and volcanoes, extraterrestrial life, and Parkinson's disease. He has even written a novel. Dr. Simon LeVay lives in West Hollywood, California.
Shamefully I read this book over a quarter century ago and at the time I remember thinking that it was all old hat. Of course a quarter century of life has unfortunately made me realise that nothing is old hat - certainly not prejudice. That so many could benefit today from reading books like this is not simply sad but horrible.
Simon LeVay’s book is the latest and most effective among the growing corpus of books and articles arguing for an exclusively biological explanation of sexual orientation. The broad and methodologically uneven array of evidence pointing to biological contributions to the origin of sexual orientation, heterosexual and homosexual, continues to amass, sprawling across diverse disciplinary areas of research. LeVay’s brilliance, sustained immersion in this subject, and scientific acumen are on display throughout the volume; an accomplished neuroscientist and compelling writer, he demonstrates in this volume an exceptional capacity for the integration of an enormous array of scientific findings. He argues passionately and persuasively for a biological understanding of the etiology of sexual orientation. Nevertheless, there are subtle problems with this volume unlikely to be perceived by the reader who does not possess background in the primary literature. What are its strengths and strategic weaknesses?
LeVay demonstrates sophistication in outlining the nature of sexual orientation, and then provides an orienting sketch of his evolving theory. He examines differences in gender-related traits and behaviors in childhood and adulthood that appear to be associated with the continuum of straight to gay sexual orientation. He argues passionately for male homosexuality understood as a result of biologically-driven feminization, and for some lesbianism as the result of masculinization:
Homosexuality is a part of a package of gender-atypical traits. Some characteristics of the bodies and minds of gay men [including sexual attraction] are shifted in a female direction compared with straight men, and some characteristics of the bodies and minds of lesbians and bisexual women are shifted in a male direction compared to straight women (273).
He examines putative hormonal, genetic, brain, physical/morphological, and birth order contributions to the shaping of sexual orientation, examining variables that could be both cause and effect of final sexual orientation. His survey is comprehensive given the limits of a volume targeted for the (very) sophisticated general reader.
In addition to the incisiveness of his analysis and persuasiveness of his prose, LeVay is to be commended for his frequent cautions that global findings about sexual orientation do not yield explanations at the individual level for the emergence of sexual orientation (for example, “I also emphasize our inability to explain in any precise way why any particular individual becomes gay or straight” [xvii]), and his usual, but not consistent, caution in his discussion of the methodological limitations of the complex body of research cited.
Even so, it gave me pause to recognize that even LeVay gets things wrong sometimes. The most egregious example occurred when, in bringing his argument to a climax, he asserted: “Perhaps the strongest clue that probabilistic processes influence sexual orientation comes from monozygotic twins. If one such twin is gay, there are roughly even odds that the co-twin will be gay or straight” (282). This kind of error, amazingly common among those arguing for biological etiology, is conclusively refuted by the very literature that LeVay cites. Recent and superior studies point to much smaller monozygotic twin concordance. LeVay himself cites the best recent study, that of N. Långström,1 who found in a huge data set compiled from the national registry for twins in the nation of Sweden that of 71 monozygotic male twin pairs in which at least one co-twin was gay, in only 7 cases was the matching co-twin also gay. Thus, LeVay should have reported that “if one such twin is gay, there is roughly a 1 in 10 chance that the co-twin will also be gay.” This is a substantive error, especially if this is “perhaps the strongest clue.” I detected this error in his discussion of literature with which I am intimately familiar, recognition of which compromised my confidence in his accuracy of coverage of research with which I have less familiarity.
A second problem with the volume was LeVay’s tendency to employ creative explanations and alternative hypotheses to explain away findings inconsistent with his theory. In one place, he reviews the inconsistent evidence for the hypothesis that homosexual orientation is partially caused by a gay man having older brothers, and he explains away studies that failed to find the effect with an appeal to “methodological issues, atypical samples, or pure chance” (254). With some consistency, he only applies such logic to studies that do not bolster his theory. Similarly, when citing the meager and questionable literature suggesting that gay men have larger family sizes (siblings, cousins, aunts and uncles, thus defeating the claim that homosexual orientation could not have a genetic basis because its lack of reproductive advantage would result in its extermination), LeVay bolsters the one supporting study by dismissing the parallel disconfirming study, saying “this latter finding might have resulted from a recruitment bias” (183). This tendency to distill strong support from a conflicted literature by explaining away disconfirming studies crops up often throughout the volume.
The big problem with LeVay’s argument, however, is the inconsistent way he frames his theory. At a few points in the book he suggests that the core question is not whether there is a biological causal effect but rather what size is the biological effect. This is the right way to begin to frame the question, to which we must add the crucial second half of the question of what kinds of other variables contribute alongside the biological ones. Someone like myself can embrace that biology contributes to the causation of sexual orientation, even significantly, but can still argue about the size of that influence and the nature of other factors. I might read the literature and think that identifiable biological causes are 20% of the total etiological package, and LeVay might argue for 50 to 60%; the complementary question is how we are to understand the causative remainder.
Throughout the book, LeVay, to my understanding, not only overestimates the power of identifiable biological etiological variables, but problematically attributes the unexplained remainder only to chance and various types of biological “static.” He frequently frames the argument as if the only two etiological theories are total biological causation or total environmental causation. At no point does he engage a true interactionist hypothesis where experiential variables (familial, peer, cultural) can interact with biology. He is unrelenting and emphatic in his resistance to any environmental variables having causal influence of any kind in concert with biological variables. Amazingly, he asserts, “there is no actual evidence to support any of those ideas” (271). Similar indefensible absolute assertions mar this work throughout. To the contrary, examples abound of significant sociocultural influences on sexual orientation.2
The other major problem in LeVay’s analysis is his failure, on a systematic basis, to reckon with the pervasive problem in this literature of unrepresentative samples. He recognizes this problem in certain areas, describing, for instance, how the initial (and highly publicized) report that gay men have a disproportionate ratio of counterclockwise hair whorls on the crowns of their heads has been utterly disproven by better studies of more representative samples. Unfortunately, the lesson learned is not systematically applied to other important research areas.
Most notably, he fails to contextualize earlier identical twin studies and earlier tests of the “older brother” hypothesis, both conducted on biased samples recruited through advertisements in the gay community, in favor of later, superior studies on representative samples. Regarding the very influential “older brother” hypothesis, LeVay treats as equivalent earlier studies conducted on advertisement-recruited gay samples, and later, ever more representative samples. My quick summary of this literature would be that the early, advertisement-recruited samples showed significant such effects. Then A. F. Bogaert3 analyzed two smaller nationally representative samples, finding an exceptionally weak “older brother” effect for only same-sex attraction (no effect for same-sex behavior), followed by his analysis4 of an enormous representative sample eight times the size of his previous studies, only to find the “older brother” effect had disappeared! The other latest studies, one of 2 million Danes5 and another of 10,000 American teenagers,6 also failed to find the effect. LeVay’s conclusion is “that gay men do have significantly more older brothers, on average, than straight men” (254). The better conclusion is that larger and more representative studies erode confidence that the “older brother” effect even exists. Much of LeVay’s other evidence cited in support of his theory likely suffers from similar problems with volunteer- and advertisement-derived samples of questionable representativeness. Might future research also see those putative effects shrinking in effect size?
Two final problems. First, throughout the book LeVay refers to “pre-gay” children, particularly “pre-gay boys.” This is one tangible place where his cautions that global findings about sexual orientation do not yield explanations at the individual level for the emergence of sexual orientation go out the window. It is indisputable that highly feminized boys and highly masculinized girls are, on average, more likely in adulthood to manifest homosexual orientation. But given that many such children never become gay or lesbian, to refer to atypical children as “pre-gay” strikes me as reckless. Such sentiments convey a sense of determinism that is unwarranted, and facilitates the many voices telling parents today, falsely, that gender-atypical children are going to become homosexual.
Finally, I was stunned by LeVay’s treatment of early sexual experience of children and adolescents. In discussing the influence of “one’s first sex partner,” he states that
[it may not be necessary] to assume that the children or adolescents were sexually passive targets for molestation by their elders. In reality, it is likely that many of them, especially the adolescents [and thus not excluding the pre-adolescents], already felt sexually attracted to same-sex partners. If so, they may have initiated the contact or responded willingly to the older person’s advances. (35) Whatever he meant, to make a comment that appears to “blame the victim” for such early experiences seems unwise.
This book provides the most comprehensive and thoughtful review available of the scientific evidence for biological contributions to the etiology of sexual orientation. Read with discernment, it provides a helpful guide to this intriguing and contentious field.
Well researched and willing to point out the flaws in all sides of the argument concerning the various scientific inquiries into homosexuality. Highly recommended.
THE AUTHOR OF THE FAMOUS 1991 BRAIN STUDY TAKES A HISTORICAL LOOK
He wrote in the Introduction to this 1996 book, "What causes a person to be gay, straight, or bisexual? And who cares? These are the twin themes of this book... this book attempts to portray research into homosexuality in its social context... In the concluding chapter I attempt to make the case that research into homosexuality is worth pursuing... because this research may indeed ... help the larger society recognize what gays and lesbians have generally believed about themselves that their sexual orientation is a central, defining aspect of their identity." (Pg. 1, 7, 9)
He notes, "Most people know that the 10 percent figure derives from the Kinsey Reports, but few people know that it applies only to men... In fact, Kinsey estimated that only about 4 percent of men were exclusively homosexual throughout their adult lives, and the figures for women were even lower... The recent surveys have consistently produced figures lower than 10 percent. In the British study cited earlier, 1 percent of the men and only 0.5 percent of the women said that they were sexually attracted `mostly' or `only' to people of their own sex, and the same percentage stated that they had had `genital contact' with a person of their own sex within the previous five years... Quite similar results have been obtained in surveys carried out in France (men only) and Norway." (Pg. 61-62) He adds that "gay people, especially men, are liable to develop a wholly inflated notion of the prevalence of homosexuality, based on their immediate environment." (Pg. 63)
Of females with congenital adrenal hyperplasia (CAH)---which causes much higher levels of androgen---"When CAH girls grow up, they are more likely than other women to experience sexual attraction to women, or to both women and men... the results strongly support the belief that hormones do play a significant role." (Pg. 122-123)
Of his own studies ("I set out to test the idea that the size of [brain] structures such as INAH3 might vary with sexual orientation as well as with sex"), he frankly admits, "it is important to stress several limitations of the study. First, the observations were made on adults who had already been sexually active for a number of years. To make a really compelling case, one would have to show that these neuroanatomical differences existed early in life---preferably at birth. Without such data, there is always the theoretical possibility that the structural differences are actually the RESULT of differences in sexual behavior... Another limitation arises because most of the gay men whose brains I studied died of complications of AIDS... there is always the possibility that gay men who die of AIDS are not representative of the entire population of gay men." (Pg. 143-144)
He notes, "Although homosexual BEHAVIOR is very common in the animal world, it seems to be very uncommon that individual animals have a long-lasting predisposition to engage in such behavior to the exclusion of heterosexual activities. Thus, a homosexual orientation, if one can speak of such a thing in animals, seems to be a rarity." (Pg. 207)
He critiques the infamous Bieber study [Homosexuality: A Psychoanalytic Study]: "Considering that most of these men were not exclusively homosexual to start with, that they were unusually motivated to change their sexual orientation, that the treatment was extraordinarily arduous and expensive , that the men were not followed up after the termination of their treatment... the Bieber study seems more like a testament to the immutability of homosexuality than its mutability." (Pg. 242)
This frank and detailed historical study will be "must reading" for anyone interested in this issue.
The book itself is excellent – even-handed and accepting the limits of scientific enquiry as it was when the book was written (1996). But diagnostic methods, both in brain-scanning technology and endocrinology, have improved so much in the intervening quarter of a century that I constantly felt that the book needs an update in those many areas where the author suggests that the next few decades will shed more light on the biological basis of ‘queerness’ (if the term is acceptable). Since the author is now 81, he may feel that his contribution to the debate has been accomplished (and in my opinion well accomplished), but it is to be hoped that other well qualified authors might take up the challenge and build upon Simon LeVay’s outstanding work.
The research presented on the effects on sexual orientation of exposing prenatal mice to hormones was useful to me. I think it's a good explanation of why transgendered people are more likely to have abnormal sexual orientations as well and why some homosexual/lesbian people have some traits of the opposite gender (another topic discussed in the book).
The discussion and analysis of findings on the prevalence of homosexuality was useful as well.
The points about what ethical conclusions we can get from these empirical findings were as good as it tends to get most books.