"Why Men Rape" by Randy Thornhill and Craig T. Palmer, in The Sciences (Jan.–Feb. 2000), New York Academy of Sciences, Two E. 63rd St., New York, N.Y. 10021.

What makes the rapist different from other men is not his sexual desire but his lust for power over women, an unnatural urge born of a sick society in which females are regarded with fear and contempt. That’s what many feminists and social scientists believe these days, but it’s dangerously misleading, say Thornhill, an evolutionary biologist at the University of New Mexico, in Albuquerque, and Palmer, an evolutionary anthropologist at the University of Colorado at Colorado Springs. Rape, they argue, "is, in its very essence, a sexual act [which] has evolved over millennia of human history."

The two authors disagree about rape’s precise evolutionary function. Thornhill believes that rape has evolved as "one more way [for males] to gain access to females" in order to pass on their genes, a sexual strategy for males who lack "looks, wealth or status" or see low costs in coercive copulation. Palmer believes "that rape evolved not as a reproductive strategy in itself but merely as a side effect of other adaptations, such as the strong male sex drive and the male desire to mate with a variety of women."

But whether adaptation or byproduct, both agree that "rape has evolutionary--and thus genetic--origins," and that this explains some "otherwise puzzling facts." Among them: that most rape victims are of childbearing age, and that rapists seldom use more force than needed to subdue or control their victims. "The rapist’s reproductive success would be hampered, after all, if he killed his victim or inflicted so much harm that the potential pregnancy was compromised," the authors say. Moreover, while some partisans in the rape debate deny it, rape does occur in the animal world (among scorpionfly species, for instance).

That rape is "a natural, biological phenomenon," Thornhill and Palmer emphasize, does not mean that it is justified or inevitable. But to be effective, preventive measures must take into account rape’s evolutionary roots. Young men should be taught "to restrain their sexual behavior." Young women should be told the truth: "that sexual attractiveness does . . . influence rapists," that provocative dress "can put them at risk," and that they should be careful about being alone with men. "As scientists who would like to see rape eradicated," say the authors, "we sincerely hope that truth will prevail" over the "politically constructed" notions about rape now in vogue.