The following is a copy of an important article on evolutionary psychology which appears not to be webbed anywhere else, Coyne, J.A., "The fairy tales of evolutionary psychology." Review of "A Natural History of Rape: Biological Bases of Sexual Coercion," by Randy Thornhill & Craig T. Palmer, MIT Press, 2000. The New Republic, March 4, 2000.
The New Republic The fairy tales of evolutionary psychology. Of Vice and Men By JERRY A. COYNE Issue date: 04.03.00 Post date: 03.26.00 A Natural History of Rape: Biological Bases of Sexual Coercion by Randy Thornhill and Craig Palmer MIT Press, 272pp. [...] I. In science's pecking order, evolutionary biology lurks somewhere near the bottom, far closer to phrenology than to physics. For evolutionary biology is a historical science, laden with history's inevitable imponderables. We evolutionary biologists cannot generate a Cretaceous Park to observe exactly what killed the dinosaurs; and, unlike "harder" scientists, we usually cannot resolve issues with a simple experiment, such as adding tube A to tube B and noting the color of the mixture. The latest deadweight dragging us closer to phrenology is "evolutionary psychology," or the science formerly known as sociobiology, which studies the evolutionary roots of human behavior. There is nothing inherently wrong with this enterprise, and it has proposed some intriguing theories, particularly about the evolution of language. The problem is that evolutionary psychology suffers from the scientific equivalent of megalomania. Most of its adherents are convinced that virtually every human action or feeling, including depression, homosexuality, religion, and consciousness, was put directly into our brains by natural selection. In this view, evolution becomes the key--the only key--that can unlock our humanity. Unfortunately, evolutionary psychologists routinely confuse theory and speculation. Unlike bones, behavior does not fossilize, and understanding its evolution often involves concocting stories that sound plausible but are hard to test. Depression, for example, is seen as a trait favored by natural selection to enable us to solve our problems by withdrawing, reflecting, and hence enhancing our future reproduction. Plausible? Maybe. Scientifically testable? Absolutely not. If evolutionary biology is a soft science, then evolutionary psychology is its flabby underbelly. But the public can be forgiven for thinking that evolutionary biology is equivalent to evolutionary psychology. Books by Daniel Dennett, E.O. Wilson, and Steven Pinker have sold briskly, and evolutionary psychology dominates the media coverage of the science of evolution. (It has figured also in the media's treatment of politics, as when the lustful activity of Bill Clinton was explained--or explained away--by various evolutionary psychologists as the behavior of an "alpha male.") In view of the scientific shakiness of much of the work, its popularity must rest partly on some desire for a comprehensive "scientific" explanation of human behavior. Evolutionary psychology satisfies the post-ideological hunger for a totalistic explanation of human life, for a theory of inevitability that will remove many of the ambiguities and the uncertainties of emotional and moral life. Freud is no longer the preferred behavioral paradigm. Now Darwin is ascendant. Blame your genes, not your mother. Hence the excitement--and the furor--that has greeted the publication of Randy Thornhill and Craig Palmer's book. Determined to show that human rape is a "natural, biological phenomenon that is a product of the human evolutionary heritage," Thornhill and Palmer take issue with social scientists and feminists (viewed as permanently conjoined Siamese twins) for whom rape represents men's deliberate attempt to subjugate and to humiliate women. In their account, by contrast, the motive for rape is not just sexual; it is also reproductive. Rape, they argue, was favored by natural selection to give sexually dispossessed males the chance to have children, or males with mates the chance to have extra children. There are several mechanisms by which such a [sexual] strategy could function. For example, men might resort to rape when they are socially disenfranchised, and thus unable to gain access to women, through looks, wealth or status. Alternatively, men could have evolved to practice rape when the costs seem low-- when, for instance, a woman is alone and unprotected (and thus retaliation seems unlikely), or when they have physical control over a woman (and so cannot be injured by her). They further claim that attempts to root out rape will not succeed until one accepts its evolutionary origin and uses this precious knowledge as a basis for social policy. Not only does an evolutionary approach generate new knowledge that could be used to decrease the incidence of rape; some of the proposals put forth by individuals uninformed by evolutionary theory may actually increase it. The coverage of A Natural History of Rape in the media has been critical, but largely devoted to pitting Thornhill and Palmer against feminists, who see the book as a misogynistic attempt to justify rape and to unravel the progress of recent decades. The results were predictable and largely unproductive: a lot of sound bites and shouting in television studios. Meanwhile the book has been warmly embraced by some evolutionary psychologists, notably by Pinker, who has praised it as a "courageous, intelligent and eye- opening book with a noble goal." Nearly all of these public debates have been fuelled by ideology. (Again, evolutionary psychology functions very much like an ideology.) What has been missing is a discussion of the science that lies behind, or does not lie behind, Thornhill and Palmer's assertions. After all, the book is only as good as their evidence. Thornhill and Palmer have frequently invoked the authority of science in defense of their evolutionary conception of rape. They insist that their detractors are ideologically motivated, whereas they are dispassionate scientists whose only priority is objective truth. In their media appearances, they have implied that their science is incontrovertible, and that any dissenter from their conclusions must be philosophically or politically blinkered. This is a grotesque misrepresentation of the book's science, which has by no means drawn unanimous approbation from the scientific community. Far from it: to a scientist, the scientific errors in this book are far more inflammatory than are its ideological implications. Like so much of evolutionary psychology, Thornhill and Palmer's book is utterly lacking in sound scientific grounding. Moreover, the authors use rhetorical tricks that mislead the general reader about their arguments. Once its scientific weaknesses are recognized, The Natural History of Rape becomes one more sociobiological "just-so" story--the kind of tale that evolutionists swap over a few beers at the faculty club. Such stories do not qualify as science, and they do not deserve the assent, or even the respect, of the public. II. Thornhill and Palmer's thesis is based on certain current ideas about the evolution of sex differences. It is obvious that men and women show clear differences in many visible traits, from body size to breasts. No biologist would deny that these differences resulted from natural selection acting on our ancestors. (A wide pelvis for women, for example, is essential in childbirth.) And given the agreement on the evolutionary basis of physical differences, it would seem foolish to deny a priori that evolution did not also produce some behavioral differences. It is true that human culture and learning may affect behavioral traits more readily than morphological ones, but there is convincing evidence that some behavioral differences evolved because they increased the reproductive success of our ancestors. Since rape is an act of sexual aggression, the pertinent question is whether males and females evolved to differ in aggression and in sexual behavior. Most evolutionists believe that they did. Of course, there are aggressive and sexually promiscuous women as well as meek and monogamous men; but we are talking averages here. Evolved differences need not be seen in every individual: many men are smaller than the average woman. In mammals, we see a fundamental asymmetry between the roles of the two sexes. Females must invest a great deal in their offspring (in the case of humans, nine months of metabolic trauma plus untold years of nursing and subsequent aggravation), while males can get away with investing very little (minimally one dose of sperm, before moving on to the next female). This leads, in general, to a marked difference in mate- selection strategies between the sexes. For the female, it pays to be prudent and picky: she has relatively few shots at reproduction, so she must make each opportunity count by choosing the best possible father for her children. The male has a different approach: he wants to inseminate as many females as possible. He is interested in quantity, not in quality. For this reason, males inevitably compete for access to females. Darwin recognized that such competition occurs in two fundamentally different ways: either males try to impress the females (the peacock strategy) or they try to directly dominate the other males (the deer strategy). It is the latter course that seems most pertinent to the sexual behavior of humans, and it is this internecine male competitiveness that is assumed to have driven not only the evolution of increased male body size (on average, bigger is better in a physical contest), but also of hormonally mediated male aggression (there is no use being the biggest guy on the block if you are a wallflower). Whatever the role of culture--of "nurture" rather than "nature"--in determining our behavior, our evolutionary legacy is certainly alive and well in the difference in size between males and females, and in those aggression-promoting male hormones. It is no accident that most rapists, and most violent criminals, are men. Feminists are undoubtedly right to claim that culture reinforces sexual stereotypes; but still there can be no adequate explanation of patriarchy that completely ignores evolution. Thornhill and palmer perform a rather ingenious trick by advancing two disparate theories, both in support of the idea that rape is "natural and biological." The first is called the "byproduct hypothesis," which maintains simply that rape is a side effect of other evolved human traits. In other words, rape is "evolutionary" because it is performed by men whose brains, bodies, and behavior have evolved to a point at which rape is physically and emotionally possible. This is a reasonable view--indeed, a tautology--that few biologists will find objectionable. The second hypothesis is called "direct adaptation," and it maintains that rape is much more than an evolutionary by-product: it is a direct adaptation installed by natural selection to allow sexually disenfranchised men to produce children. This latter view is far more controversial, and it is clearly the centerpiece of Thornhill and Palmer's book. Nearly all of the discussion and the cited evidence are directed at proving the truth of this second theory. III. The "by-product hypothesis" views rape as a mere side effect of other adaptations that natural selection built into our ancestors. That is, natural selection did not favor genes impelling men to rape, but genes for other features of human emotion and behavior that, in combination with human culture, allow the existence of rape. Thornhill and Palmer are not explicit about which evolved features produce rape as a side effect, but a good guess is a mixture of male promiscuity and aggression. This mixture, especially if combined with a male animus toward women, might readily explain rape. In this view, rape is an act of sexual violence--an outlet for rage and sexual release directed at a convenient target. It is an act of sex and violence, with one or the other predominating according to circumstances (date rape is more sexual, the violent rape of strangers is more aggressive). Given that rapists, in most reported cases, are sexually aroused and often reach orgasm, and that some convicted rapists admit to erotic motives, it is hard to disagree with Thornhill's and Palmer's claim that rape is at least partly a sexual act. But this claim is hardly new. Indeed, the sexual dimension of rape is painfully obvious. But Thornhill and Palmer assert that "academic feminists and sociologists" have consistently denied any sexual motivation for rape, insisting instead that "rape is not about sex, but about violence and power." It is true that in recent decades the discussion of rape has been dominated by such notions, though one must remember that they originated not as scientific propositions but as political slogans deemed necessary to reverse popular misconceptions about rape. The real problem with the by-product hypothesis is its banality. It explains everything about human beings. Since we have an evolutionary history, everything that we are and everything that we do can be furnished with an evolutionary explanation. There is no behavior that does not originate in our having a brain that is the product of natural selection. And this opens the evolutionary floodgates. Playing the violin? A by- product of creativity, manual dexterity, and the ability to learn. Collecting stamps? A by-product of our evolved desires to acquire resources and to categorize our environment. But such explanations are crushingly trivial. The triviality of the by-product theory may be seen in Thornhill and Palmer's declaration: When one is considering any feature of living things, whether evolution applies is never a question. The only legitimate question is how to apply evolutionary principles. This is the case for all human behaviors-- even for such by-products as cosmetic surgery, the content of movies, legal systems, and fashion trends. Well, if Thornhill and Palmer want to lump rape together with tummy tucks and Titanic as "evolutionary" phenomena, God (or Darwin) bless them. We might as well throw in adoption (a byproduct of parental care), masturbation (a by-product of uncontrollable sexuality), bestiality (ditto), and priestly celibacy (a by- product of religion, which is itself a by-product of some evolved feature that nobody understands). Of course, the interesting thing about masturbation, adoption, bestiality, and celibacy is that they are maladaptive traits: they could never have been favored by natural selection because their practice reduces the chance of propagating one's genes. And we should not forget non-sexual crimes such as murder, assault, and robbery--all those other by-products of evolution. The key phrase in the passage that I have just adduced is "whether evolution applies is never a question." This is an explicit admission that the by-product hypothesis lacks the defining property of any scientific theory--the property of falsifiability, the ability to be disproven by some conceivable observation. An unfalsifiable theory is not a scientific theory. It is a tautology, or an article of faith. The by-product theory may justify the view of rape as an evolutionary pathology, an indirect consequence of male sexuality and aggression; and the byproduct theory may also justify the feminist view that rape is simply a way for males to dominate and humiliate females. And so we can dismiss the by-product hypothesis, because there is no observation that could disprove it. IV. After proposing the by-product hypothesis as their fallback position, Thornhill and Palmer introduce the centerpiece of their book: the direct-selection hypothesis. This theory holds that rape is not merely an aggressive act or a sexual act, but a reproductive act--that is, one inserted by natural selection into men's brains. As the story goes, men who lack committed relationships and are unable to find mates in the usual ways can produce offspring by raping unwilling women. The frequency of genes causing rape would increase at the expense of genes carried by equally disenfranchised but nonraping males, who leave no offspring. This would eventually lead to the brain's acquisition of a "rape chip," a behavior as hardwired as our tendencies to sleep and to eat. In the direct-selection theory, all men are born as potential rapists, but they do not necessarily rape because the effect of the act on reproduction depends on external circumstances. For one thing, rape can be favored by natural selection only when it gives rapists a net reproductive gain. Thus, Thornhill and Palmer suggest that natural selection has also endowed men with the ability to perform a reproductive cost-benefit analysis before raping. The benefit is the likelihood that the act will produce a genetically related offspring. The cost is that the rapist might be caught and severely punished, depriving him of future offspring. Men will therefore rape when they are most likely to get away with it. Moreover, the theory predicts that men are selected to evaluate not just circumstances but also victims, choosing those most likely to be fertile. As with all behavioral adaptations, the rapist need not be conscious of the evolutionary wellsprings of his actions, just as we do not ponder the need to stoke our metabolism when sitting down to dinner. Viewing rape as a module of the male brain is provocative enough; but Thornhill and Palmer go on to propose, in the manner of evolutionary psychologists, that many other aspects of rape are direct adaptations. While they see rape as adaptive for men, they concede that it is not so for women, who suffer physical violence, emotional trauma, possible alienation of their partner, and loss of their own evolved ability to choose the best mate. Natural selection therefore gives women their own adaptation: the post-rape trauma. "Psychological pain is an adaptation that functions against such [reproductive] losses by focusing on the causes of the losses. The result is that attention is directed toward ways of dealing with current circumstances, given the loss, and of avoiding a repetition of events that caused the loss." (As I have noted, others have proposed a similar explanation for the evolution of depression. I doubt, though, whether rape victims and depressives use their trauma so productively.) And since the partner of a rape victim may be unsure whether a subsequent child is his, Thornhill and Palmer propose yet another direct adaptation: male suspicion about their mate's claim that she was raped. That, too, is biologically mandated. Finally, in a theory almost unbelievably grandiose, Thornhill and Palmer suggest that the opposition to their theories is itself based on evolution. Our brains, they say, are so much the product of evolution that they have been preprogrammed with a set of beliefs, one of which is a reluctance to believe explanations involving evolution: "Evolved psychological intuitions about behavioral causation can mislead individuals into believing that they know as much as experts do about proximate human motivation." Don't like the theory? Trust the "experts," who have painfully overcome their aversion to evolution. (This is one of the ways in which the new evolutionary psychologists resemble the old Marxists: there is no place to stand outside their system of meaning, except for the privileged place where they themselves stand.) Although Palmer himself professes to favor the "by-product hypothesis," the authors continuously push the mixture of directly adaptive theories that I have just described. The direct-selection theory first appears in the fourth chapter of the book, and the remaining eight chapters are devoted to discussing this theory alone and its implications for society. All of the evidence supplied supports the view that rape is a direct adaptation, and not an evolutionary by-product. (The latter theory requires no evidence because it is true by definition.) Thornhill and Palmer employ three lines of evidence to support the direct-selection hypothesis. First, they maintain that rape occurs as an adaptive phenomenon in other species, and thus could have evolved by the same route in humans. In scorpion flies, Thornhill's own research organism, males have an abdominal clamp that apparently evolved to help them forcibly restrain females who resist their courtship. Several other species also seem to show forced copulation, although whether it increases the male's reproduction is not known. But surely it is absurd to assume that rape may be a reproductive strategy in humans because it is a reproductive strategy in flies or ducks. Flies and ducks do not create, and live in, a culture, as humans do; and human culture guarantees that there will be many meaningless parallels between the behavior of humans and of other species. Like dandelion seeds, we parachute, but we do so for recreational reasons, not for reproductive reasons. The simple-minded extrapolation from a handful of animal species is no proof that human rape is a direct adaptation. The second test of the theory involves performing the actual reproductive calculus of a human rapist. Do rapists really have more children over the course of their lives than equally dispossessed but non-raping males? This calculation cannot be made, given the large number of unreported rapes (figures range from fifty percent to 80 percent) and of rapists who are never caught. According to Thornhill and Palmer, a single rape in peacetime has about a two percent chance of producing pregnancy. The problem is that we will never know the reproductive costs. Does the chance of being caught lower a rapist's future reproductive output by more than two percent? Indeed, such a calculus, based on modern statistics, may be completely irrelevant to judging the costs and the benefits obtaining when rape really evolved. As the authors note, the selection that built any "rape module" probably occurred in our distant evolutionary past, when society was not at all like ours. Human civilization, after all, arose in only the last one-tenth of one percent of the interval since we branched off from our primate ancestors. All that we can say, therefore, is that the reproductive benefits of ancestral rapists may have been lower than those of modern rapists (because of a lack of contraception, it is possible that females were pregnant far more often than they are now, and subsequent nursing of a child usually suppresses ovulation); and the costs may well have been higher (given the lack of jails, punishments for rape were probably more severe, and the chances of getting caught higher in small social groups). But the important point is that all such speculations remain mere stories about our unrecoverable past. Thornhill and Palmer are undoubtedly right to note that current observations about rape may bear little relation to forces acting in our ancestors; but then they ignore their own warnings, and proceed to argue for the direct-selection hypothesis by using statistics from modern Western societies. The highlight of Thornhill and Palmer's evidence--their third method of supporting the directselection hypothesis--is a series of "predictions" about what one would expect to see if rape had evolved as a direct adaptation. These predictions (all supposedly verified by the authors' research) are meant to confer the prestige of rigorous science upon their argument. Examined closely, however, the scientific evidence fails, and on three counts. First, it is hard to see from modern statistics that rape increases reproduction. Thornhill and Palmer make much of their verified prediction that women of reproductive age are overrepresented as rape victims, as one might expect if rapists prey on potential childbearers. But looking closer, one finds that a significant number of rape victims are either too old or too young to reproduce. According to Thornhill and Palmer themselves, one cited study showed that twenty-nine percent of victims were younger than eleven. (This estimate of underaged victims may be low, given the frequency of unreported child molestation.) Other studies concur; and, when one adds in post-menopausal women, at least a third of all female rapes involve victims who cannot reproduce. Also, roughly twenty percent of all rapes do not involve vaginal penetration, and fifty percent of all rapes do not include ejaculation in the vagina. So these (although there is some overlap between these classes) must also be excluded from the reproductive category. Thornhill and Palmer note that while few rapes in peacetime are accompanied by murder--as expected if it is a reproductive act--more than twenty-two percent of rapes involve violence in excess of what is needed to force copulation. This rather plainly supports the view that at least some rapes involve anger and gratuitous violence, and are not completely motivated by a desire to reproduce. Moreover, roughly ten percent of all rapes in peacetime are gang rapes, and, insofar as they involve more males than are needed to overcome the victim, they must be considered less adaptive than individual rapes because competition between ejaculates lowers each rapist's chance to reproduce. Although we lack hard statistics, anecdotal evidence also suggests that many wartime rapes involve large groups of soldiers, and often culminate in the murder and the sexual mutilation of the victim. These, of course, are acts of sexual violence, pure and simple, and cannot in any way be attributed to reproduction. And what about wartime bordellos, such as those set up by occupying Japanese during World War II, in which kidnapped women were repeatedly raped by many different soldiers? Finally, same-sex prison rapes, which in most states are not even counted as rapes, cannot produce offspring, but involve the subjugation of victims for sex, power, and humiliation. There are thus a great many rapes that cannot be explained as attempts to reproduce. V. Of course, not all biological adaptations are perfect, or apparent in every individual. Anorexics, for example, clearly contravene our evolutionary dictate to eat. Still, the large number of exceptions to what is proposed by Thornhill and Palmer as a direct adaptation is disturbing. The problem is that they never specify what percentage of rapes need be potentially reproductive to show that rape evolved. Fifty percent? Eighty percent? (Indeed, the vaginalejaculation data show that the proportion of "reproductive" rapes cannot exceed fifty percent; and this upper limit becomes even smaller if we include male victims.) As with most sociobiological arguments, only some level of concordance with prediction need be found to brand an act as an adaptation. Faced with many clear cases of nonadaptive rapes, Thornhill and Palmer revert to their fallback positions: the byproduct hypothesis, and special pleading about the different conditions of our evolutionary past. Thus, confronted by the annoying fact that some rapists have wealth and high status, the authors immediately invoke the by-product hypothesis: "Rape by men with high status and abundant resources may arise from a combination of impunity and the hypothetical adaptation pertaining to evaluation of a victim's vulnerability. If so, their raping must result from adaptations other than that suggested by the second hypothesis [direct adaptation]...." In this way, Thornhill and Palmer have constructed an apparently airtight case, an argument that cannot be refuted. Aspects of rape that seem adaptive must have evolved by direct selection, while nonadaptive aspects are seen as evolutionary holdovers or as by-products. Lawyers call this "arguing in the alternative." It is not science, it is advocacy. And if many rapes can be written off as nonadaptive acts, why don't Thornhill and Palmer even consider the possibility that all rapes might be nonadaptive? And there is another difficulty that Thornhill and Palmer do not face. For nearly all of their observations, there are reasonable alternative explanations that do not involve direct selection. As predicted by the directselection hypothesis, for example, rapists tend to be young men from lower socioeconomic classes, who supposedly have limited access to mates. (Thornhill and Palmer offer no evidence, by the way, for a correlation between class status and access to mates.) But such men are disproportionately represented among all violent criminals, including those committing murder, armed robbery, and assault. Why does this observation confirm the direct-selection hypothesis, instead of the simpler view that deprived, angry males commit violent acts that could gain them reputation, sex, or money? Among rape victims, similarly, women between the ages of eighteen and thirty are overrepresented compared to older women, as predicted by the idea that rapists prefer fertile victims. But what is the relative vulnerability of women of different ages to being raped? Could they differ in their availability to men who would molest them, or in their relative tendency to report rape? Or could the mostly young rapists merely be finding victims within their easily accessed peer group? Why, precisely, is rape "a horrendous experience for the victim?" Thornhill and Palmer have an answer: the loss of mate choice or the alienation of existing mates. It is quite an answer. But it is not only offensive, it is also incoherent. Why not argue that any violation of the body is traumatic, with rape being the most extreme intrusion? Surely victims of homosexual rape do not walk away mentally unscathed. The reader may find it interesting, and not all that hard, to devise plausible alternatives for the other half-dozen observations that Thornhill and Palmer offer as proof of the direct-selection theory. Thornhill and Palmer also cite earlier work that seems to support the direct-selection theory, but a trip to the library shows that they misrepresent at least some of this literature. Lacking the time to look up every citation, I decided to check three claims about rape taken from Thornhill's own earlier publications. I was shocked to find that none of these claims are supported by the cited articles. According to Thornhill and Palmer, the literature shows that raped women of reproductive age suffer more trauma than do older and younger victims (this is an essential element of their argument, since they see rape trauma as a direct adaptation); that older and younger victims suffer less rape-inflicted violence than do reproductive-age women (the latter fight harder to protect their eggs, and males fight harder to fertilize them); and also that, compared to either pre-reproductive or post-reproductive victims, raped females of reproductive age experience a higher proportion of penile-vaginal intercourse (rapists can recognize fertile females). These three assertions derive from a study of 790 rape victims examined at Philadelphia General Hospital in 1973 and 1974. The results were summarized by Thomas McCahill, Linda Meyer and Arthur Fischman in The Aftermath of Rape, which appeared in 1979, and were further analyzed in three papers by Thornhill and Nancy Thornhill, an anthropologist and his former wife. In the three publications by Thornhill and Thornhill, the data show that while younger women (under twelve years) do indeed experience less trauma, violence, and vaginal rape than do reproductive-age women between the ages of twelve and forty-four, older women do not differ from reproductive-age females. The authors thus achieve their "supportive" results by sleight of hand: they lump together younger and older women when comparing them to reproductive-age women, and the difference between these "reproductive" and "nonreproductive" victims results entirely from the effect of the youngest age class. This improper combining of heterogeneous data allows the authors to state, misleadingly, that "the study showed that reproductive-age victims suffered significantly more psychological trauma than non-reproductive-age rape victims," and that "reproductive-age rape victims were more often subjected to violent attacks than victims in the other two categories." These three "predictions," then, are supported by the one comparison (younger versus reproductive) but not by the other comparison (older versus reproductive). The general claim for rape and trauma as adaptations is achieved only by fiddling with the data. This is not the way that scientists normally behave. Moreover, even the differences between the youngest class and the two older classes may be caused by phenomena other than natural selection. Lack of vaginal intercourse in younger victims (some of them babes in arms) may be due to mechanical problems. Moreover, in the trauma study, the reactions of young girls (from two months to eleven years old) were often measured in an unusual way: by consulting third parties. As noted in Thornhill and Thornhill's original paper: "the child's caretaker sometimes helped the child respond to interview questions, or with very young victims, the caretaker gave the responses to the questions based on his/her perception of the effect of the sexual assault on the child." Does anyone really believe that a third party can accurately judge the degree to which a young child suffers increased "insecurities concerning sexual attractiveness" or "fear of unknown men"? Is it possible that caretakers may consciously or unconsciously try to minimize the trauma suffered by young girls? Or that young girls--or women of any age-may show full trauma only after a period of time? (All victims were interviewed within five days of the rape.) There are other problems with these cited studies, including the failure to apply standard statistical corrections that, when used, weaken the "supportive" results; but we need not go further. The studies discredit themselves. I emphasize again that these are the only bits of supporting "evidence" that I checked. Did I happen, by chance, to find the only three inaccurate citations in the book? Thornhill and Palmer can be very nasty about those who differ with their analysis, mainly sociologists and feminists. "[A]ccording to the assumptions of the social science explanation of rape," they write, "the problem of rape could be solved simply by teaching women that rape is a wonderful experience." Also, "because the evolutionary approach threatens the theories and approaches that have traditionally been used to study human behavior, it poses a serious threat to the status of those who have achieved success in their fields using non-evolutionary approaches." Thornhill and Palmer care about truth, and everybody else cares about status. In fact, Thornhill and Palmer are accusing others of what are really their own failings: "Not only is the bulk of the social science literature of rape clearly indifferent to scientific standards; many of the studies exhibit overt hostility toward scientific approaches, and specifically toward biological approaches. The message of these studies is clearly political rather than scientific." It is Thornhill and Palmer who are guilty of indifference to scientific standards. They buttress strong claims with weak reasoning and weak data. Their book lacks the measured tone and the openness to alternative theories that characterize truly scientific work. (Compare their sledgehammer approach with the moderate tone of On the Origin of Species.) It is perfectly clear to any fair-minded reader of A Natural History of Rape that its objective is not to test whether rape is an adaptation, but to demonstrate it. Their evolutionary-psychological explanation of rape is not their conclusion, it is their premise. VI. By claiming that rape is a natural biological act, Thornhill and Palmer immediately lay themselves open to the accusation of making excuses for rapists. They repeatedly distance themselves from this accusation (who wouldn't?), properly claiming that to equate "natural" with "allowable" or "good" is a common error, known as "the naturalistic fallacy." They add that evolved biological impulses should not be used in court as a defense of rapists, even though their own work has made such a defense possible. But they do declare that social policies to eliminate rape will not work unless they take into account the crime's evolutionary origin. Their "evolutionarily-informed" suggestions are either obvious and derivable from non-evolutionary views of rape (punish rapists more harshly, teach young men not to rape, urge women to avoid secluded spots) or fatuous (build male and female summer camps farther apart, use chaperones early in a relationship) or invidious (counsel rape victims by telling them that their trauma is adaptive). Thornhill and Palmer justify Darwinian anti-rape courses for men by noting that "individuals who really understood the evolutionary bases of their actions might be better able to avoid behaving in an `adaptive' fashion that is damaging to others." Does anyone imagine that young men will be less inclined to rape when they are told that it is in their genes? Or that rape victims will be consoled by knowing that their trauma and their depression have evolutionary roots? Thornhill and Palmer also claim that women in scanty dress are more likely to be raped, and should keep this risk in mind when picking their clothes. Young women should also be informed that female choice, over the course of the evolution of human sexuality, has produced men who will be quickly aroused by signals of a female's willingness to grant sexual access.... And it should be made clear that, although sexy clothing and promises of sexual access may be means of attracting desired males (Cashdan 1993), they may also attract undesired ones. The reader will search in vain, however, for any evidence that more skin provokes more rape. The source of Thornhill and Palmer's advice on this point is a mystery. Which brings us to the largest question broached by this book. Can knowledge about evolution play a useful role in reforming society? I strongly doubt it. The best approach to stopping crime, for example, seems to be the pragmatic one: do what works best, regardless of the crime's evolutionary underpinnings. Must we study the evolutionary basis of murder to deal effectively with it? Should we think about the evolution of greed when making anti-trust laws? A useful parallel may be drawn from medicine. Can an understanding of the evolutionary origin of a disease facilitate its cure? We know both the genetic and evolutionary roots of only one malady: sickle-cell anemia. The gene that causes this disease also helps to fight malaria, and thus sickle-cell anemia is common in residents of mosquito-infested areas of Africa (and in their black American relatives). But this knowledge is of absolutely no comfort to those suffering from the disease, and it has been of no use to physicians trying to cure it. While denouncing feminists and sociologists for their misguided and scientifically uninformed attempts to deal with rape, Thornhill and Palmer overlook the major improvements that these groups effected in legal and cultural attitudes toward rape. The dropping of the legal requirement for eyewitness corroboration of rape, and the restriction of the use in court of a victim's prior sexual history; the founding of rape crisis centers; the establishment of more compassionate attitudes toward victims by police, hospital staffs, psychiatric counselors, and juries: all of these constructive policy changes were brought into being by (to use Thornhill and Palmer's phrase) "individuals uninformed by evolutionary theory." Thornhill and Palmer's attempts to gain control of rape counseling, laws, and punishments, despite the weakness of their science, reveal their larger goal: the engulfment of social science and social policy by the great whale of evolutionary psychology. This attempted takeover is not new. It was first suggested in 1978 in E.O. Wilson's On Human Nature, and more recently in his Consilience, Wilson extended the program to nearly every area of human thought, including aesthetics and ethics. We are witnessing a new campaign for the Darwinization of Everything. Thornhill's and Palmer's theory of rape is just the most recent attempt at the annexation of all human experience to evolutionary psychology. After all, if one can give a believable evolutionary explanation for the difficult problem of rape, then no human behavior is immune to such analysis, and the cause is significantly advanced. The apocalyptic tone that pervades Thornhill and Palmer's book reveals the party to which they belong: "The biophobia that has led to the rejection of Darwinian analyses of human behavior is an intellectual disaster." And "in addressing the question of rape, the choice between the politically constructed answers of social science and the evidentiary answers of evolutionary biology is essentially a choice between ideology and knowledge." Let us be clear. It is not "biophobia" to reject the reduction of all human feelings and actions to evolution. Quite the contrary. It is biophilia; or at least a proper respect for science. The "choice between ideology and knowledge" is a real choice; but it is Thornhill and Palmer and the doctrinaire evolutionary psychologists who choose ideology over knowledge. They enjoy the advantage that people seem to like scientific explanations for their behavior, and the certainty that such explanations provide. It is reassuring to impute our traumas and our misdeeds to our savanna-dwelling ancestors. It lessens the moral pressure on our lives. And so the disciplinary hubris of evolutionary psychology and the longing for certainty of ordinary men and women have combined to create a kind of scientistic cargo cult, with everyone waiting in vain for evolutionary psychology to deliver the goods that it doesn't have. Amid this debacle--for A Natural History of Rape is truly an embarrassment to the field--I am somewhat consoled by the parallels between Freudianism and evolutionary psychology. Freud's views lost credibility when people realized that they were not at all based on science, but were really an ideological edifice, a myth about human life, that was utterly resistant to scientific refutation. By judicious manipulation, every possible observation of human behavior could be (and was) fitted into the Freudian framework. The same trick is now being perpetrated by the evolutionary psychologists. They, too, deal in their own dogmas, and not in propositions of science. Evolutionary psychology may have its day in the sun, but versions of the faith such as Thornhill and Palmer's will disappear when people realize that they are useless and unscientific. JERRY A. COYNE teaches in the Department of Ecology and Evolution at the University of Chicago. [...] (Copyright 2000, The New Republic)
(Coyne, J.A., "The fairy tales of evolutionary psychology." Review of "A Natural History of Rape: Biological Bases of Sexual Coercion," by Randy Thornhill & Craig T. Palmer, MIT Press, 2000. The New Republic, March 4, 2000)
Copyright © 2007, by Stephen E. Jones. All rights reserved. This page and its contents may be used for non-commercial purposes only. If used on the Internet, a link back to this article at http://members.iinet.net.au/~sejones/coynefte.html would be appreciated. Created: 5 February, 2007. Updated: 5 February, 2007.