The Best American Science Writing 2006.

The Best American Science Writing 2006 Edited by Atul Gawande, HarperCollins, 362 pages, $14.95

DESPITE PERSISTENT political realities and occasional ideological relapses, science has never relented in its defense of curiosity, progress, and truth. Since classical times, a literally ceaseless procession of researchers and skeptics has distinguished our species as one both willing and able to overcome these struggles. Then again, the popular media's historical record, though frequently spectacular, has been far less inspiring. By November 13, however, when Time magazine featured Richard Dawkins, the outspoken Oxford zoologist also known as "Darwin's Rottweiler" in a surprisingly frank debate targeting the very existence of gods, 2006 had proven itself an exceptionally encouraging year.

Nonsectarian religious criticism, it seems, has finally exploded from its academic closet, and, more remarkably, it has done so in the United States. Small wonder, then, that Atul Gawande, surgeon and staff writer for the New Yorker, has highlighted religiously infused issues in the 2006 edition of The Best American Science Writing.

Mere mention of Pennsylvania's Dover Area School District conjures simultaneous sensations of triumph, because educational health prevailed that day, and dread, because the Dover virus hasn't been contained. Recognizing that a disease snubbed is not a disease cured, biologist H. Allen Orr briskly defends science against its most recent and recalcitrant irritant, the Intelligent Design movement, rebutting the chief contentions of its two most prominent advocates from the faith-piloted Discovery Institute, biologist Michael Behe and mathematician William Dembski.

Behe's primary argument has been that cells, for example, must have been intelligently designed because their structures and machinations are so elaborate as to be deemed "irreducibly complex" Evolution, however, can account for such intricacies in at least two ways, circuitously and directly. Ponder first the bacterial flagellum (or propeller), which consists of approximately thirty distinct proteins, each of which is required for movement. How could such an organism have evolved, Behe might inquire, when the absence of any one protein would render the flagellum completely useless? Elaborate structures, Orr responds, frequently evolve for one purpose only to be drafted or co-opted for another. The evidence in fact shows that several flagellar proteins once functioned as part of a molecular pump in the bacterial cell's membrane. Second, a part that is essential to a modern organism could have evolved directly as a nonessential but advantageous component. Orr asks us to consider an automobile's global positioning system as an appropriate analogy. We wouldn't be surprised, he vies, if computers relying on GPS technology actually drove our cars one day.

Dembski, by contrast, likens evolutionary theory to a mathematical algorithm and contends that, according to the infamous "No Free Lunch" theorems, no particular blind algorithm, including the Darwinian variety, is more effective at solving a problem than any other. Elaborate machines, in other words, don't result from sightless modification. All of which, Orr counters, is beside the point. Dembski never provides an adequate explanation as to why NFL theorems should apply to the co-evolution of organisms that adapt to a rapidly shifting array of viruses, predators, prey, and parasites. Not surprisingly, David Wolpert, author of the NFL theorems, labels Dembski's exploitation of them as "fatally informal and imprecise"

Although the Intelligent Design movement claims to be based on science, it has never bothered to construct a scientific case of its own. Despite its obvious status as little more than a political polemic, 80 percent of Americans believe that God, the conveniently unnamed but putative intelligent designer, is somehow responsible for human development. Meanwhile, as U.S. children ready themselves to assume control of the physical, intellectual, and political worlds, they are being told that neither biology nor critical thinking matter. Unsurprisingly, scientists in increasing numbers are electing to subject religion itself to scientific scrutiny.

Wasting none of his readers' valuable time, Yale Professor of Psychology Paul Bloom drives straight to the matter's heart. Summarily rejecting the notion that Americans are more religious (as opposed to merely more churched) than others, Bloom attempts to refute two common, culturally-based theories of religious origins. Freud noted that religions tend to soften nature's rough edges, the thorny problem of death in particular, and to promise eventual relief from and reward for worldly suffering. Bloom doesn't quarrel with these observations, as far as they go, but he reminds us that a person must believe an idea before he or she can gain consolation from it. Others define religion as a predominantly social utility. What binds some necessarily excludes others, of course, but religion's penchant for each function is abundantly documented. Even so, Bloom replies, humanity's need for community fails to explain religion specifically. What, he asks, can account for belief in supernatural things?

An accident of monstrous proportions, as it turns out. The human brain, Bloom explains, acquired two systems for dealing with the world. Our understanding of the physical environment, such as it is, evolved quite early. Our social intelligence, on the other hand, represents a very recent adaptation. The separateness of these systems facilitates a kind of cognitive overshooting and explains why we erroneously tend to distinguish the world of objects from the world of minds. Thus, despite the fact that the "mind" is simply what the brain does, people frequently conclude that bodies and minds (or souls) can actually endure apart from one another.

Bloom cites a study in which young children were told a story about Brown Mouse and Mr. Alligator, which predictably ended with alligator consuming the mouse. When asked about Brown Mouse's biological assets, the children answered that the mouse's organs, including her brain, no longer worked. When questioned about Brown Mouse's psychological functions, however, more than half of the children concluded that these remained viable. That kids believe in some kind of life after death to a greater extent than adults, Bloom argues, is evidence that supernaturalism is innate and not learned.

This duality of belief systems, coupled with our hypertrophic tendency to intuit purpose, design, and intent in things and under circumstances where they simply don't exist, resulted in religious supernaturalism--much as our adaptive traits of empathy and abstract reasoning effected long-distance altruism. Each, according to Bloom, is an evolutionary byproduct, the accidental consequence of a set of adaptive systems gone awry.

Two to 4 percent of American men are gay, according to most estimates, and have been denied equal treatment under the law because of it. Thus far, scientific investigation into the causes of homosexuality has been scant and underfunded, though not because the issue is uninteresting. To the contrary, scientists have been discouraged from researching the origin of homosexuality because, from religious and political perspectives, the stakes are unusually high. If homosexuality is neither a choice nor a product of one's upbringing, it becomes much more difficult to either condemn it as a sin or deny it equal protection.

Neil Swidey, staff writer from the Boston Globe Magazine, outlines the project's anemic history. Until quite recently, of course, the consensus had been that homosexuality was learned and not inbred. By 1991, however, neuroscientist Simon LeVay's study of men's brains revealed that a mass of neurons within the anterior hypothalamus, which is believed to manage sexual behavior, tended to be twice as large in gays as in straights. Soon thereafter, psychologist Michael Bailey calculated that if one male identical twin was gay, the other twin had a 50 percent chance of being gay as well. That rate was only 20 percent in fraternal twins. In 1993 Dean Hamer discovered that homosexual brothers shared a specific region of their X chromosome, labeled Xq28, at a higher rate than other homosexuals shared with their heterosexual brothers.

In 2005 Swedish researchers observed that the hypothalami of gay men light up to the scent of male perspiration, whereas the same tissues in straight men reacted to the smell of female urine instead. Using MRI scans, Northwestern University scientists recently found that homosexual men become aroused when shown images depicting only gay sex. Interestingly, most women, whether they identified as straight, lesbian, or bisexual, were aroused by all three varieties of sex.

According to Swidey, accumulating evidence now suggests that sexual orientation, like sexual identity, might be determined by masculine hormone exposure, or lack thereof, in the womb. Psychiatrist and urologist William Reiner, for example, has learned that among boys who were raised as girls, only those who lacked a masculine hormone "receptor" ended up being attracted to males. Although skeptical, Swidey suspects that genes are controlling the outcome, whether by prescribing the size of the neural mass in our hypothalami or by regulating hormone exposure. In any case, he concludes, the fact of homosexuality appears to be set prior to a child's birth, at least in men. The question remains, however, as to how gayness can be squared with evolution, given that homosexual men are said to produce 80 percent fewer children than their straight counterparts.

One can only hope that religious and political forces will permit scientists to continue and expand their investigation of these issues, and, as such research progresses, that the general media will muster enough courage and inspiration to make it public.

Kenneth W. Krause is a former prosecutor and criminal defense attorney with degrees in law, history, literature, and fine art. Books editor for Secular Nation, he has recently contributed to Free Inquiry, Skeptic, Skeptical Inquirer, and the Humanist.