Gay, Straight, and the Reason Why by Simon LeVay Oxford University Press, 2010; $28; 412 pp.
We all have our quirky preferences: Some don’t like it when food touches other food on their plate, or when socks don’t match up. But are our selves shaped by outside influence, or did we enter the world this way? Was our behavior learned or innate? In Gay, Straight, and the Reason Why, you’ll find answers to similar questions of a more intimate sort.
Nearly two decades ago, Simon LeVay published a scientific paper asserting that gay men differed from straight men in their brain structures — specifically, a cluster of nerve cells controlling sex drive in gay men were the same size observed in straight women’s brains. Since publication of that paper, vast amounts of research have probed same-sex attraction and the nature/nurture debate. Here, LeVay takes a deeper look at some of the newer findings.
While some gays and lesbians are surprised later in life by feelings of same-sex attraction, LeVay says that sexual identity, while not always immediately apparent, is present at birth (although women, throughout life, appear to be more fluid). He points to several cases in which male infants were, for one reason or another, “assigned” to live as the opposite sex. In most cases, upon adulthood, the “assignment” turned out to be wrong.
Some theorize that childhood abuse has influenced gayness, but survivors deny it as a factor. Some theories claim that older siblings or domineering parents hold sway. And as for “choice,” LeVay cites several quasi-claims of “conversions” in which therapy reportedly changed sexual preference.
Overall, LeVay says, nothing is cut-and-dried, but the probable reason that someone is gay has to do with genetics, hormones and stress that individuals receive in utero. Studies show, for instance, that mice are influenced by chemicals secreted by their mothers and by littermates. Humans, likewise, are affected in similar ways, which could lay to rest many questions. And one of the hints may literally be at your fingertips.
While there’s no doubt Gay, Straight, and the Reason Why is an intriguing book that makes sense on several levels, there’s one big problem with it: you almost need a Ph.D. to follow much of what LeVay says. It’s steeped in medical lingo, and while LeVay includes a glossary and substantial notes to explain the scientific terms and acronyms, this book is a challenge.
But if you’re up for that challenge, you’ll be rewarded with a thought-provoking examination of a private subject that has a very public focus. LeVay leaves no hypothesis unexamined, which leaves readers satisfied that every corner of this argument has been thoroughly dusted off.
Give yourself some time if you decide to tackle this book, because it’s nowhere near light reading, but it is fascinating — and ultimately a plea for tolerance.

— Terri Schlichenmeyer

This article appeared in the Dallas Voice print edition November 26, 2010.