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. Last Updated: 07/27/2016

Darwinian Theory of Rape Sparks Fury

Rape is primarily a crime of violence and power, not sex. Or so a generation of social scientists and feminist scholars have argued.

But in a forthcoming book, two evolutionary scientists say this view is born of ideology, not science, and is "based on empirically erroneous, even mythological, ideas about human development, behavior and psychology."

In fact, they assert in "A Natural History of Rape: Biological Bases of Sexual Coercion," that rape "is in its very essence a sexual act" and that the practice may have evolved because it confers an evolutionary advantage.

All of which, given the current passion for pulling Darwin into the domain of human sexual affairs, is not particularly new. But Dr. Randy Thornhill, Regent's professor at the University of New Mexico, and Dr. Craig Palmer, an anthropology instructor at the University of Colorado, go further: If rape prevention programs are to be successful, they contend, evolution must be taken into account. They recommend, among other things, advising women that "the way they dress can put them at risk." They also recommend instructing young men, before they are granted drivers' licenses, that "Darwinian selection" is the reason a man "may be tempted to demand sex even if he knows that his date truly doesn't want it" or "may mistake a woman's friendly comment or tight blouse as an invitation to sex."

The book's thesis is already provoking discussion - and anger.

Dr. Jerry Coyne, an evolutionary biologist at the University of Chicago who has read an excerpt that appears in the current issue of the journal The Sciences, called it "the worst efflorescence of evolutionary psychology that I've ever seen."

"It's irresponsible, it's tendentious, it's an advocacy article and the science is sloppy," he said. "There are some aspects of human behavior that are fairly clearly evolutionary. But that's a long way from saying that rape is adaptive in males."

Dr. Mary Koss, an authority on rape and a professor of public health at the University of Arizona, says that evolution is a factor in rape.

She cautioned, however, that "it is not proper to set up evolutionary and social causation as opposites," adding, "You have to think about how they work together."

Koss dismissed the notion that men should be educated about the evolutionary origins of rape. "If you even imply to a male audience that all men are potential rapists, they go berserk," she said.

And she called the recommendation that women consider the risks of dressing attractively "absolutely, perfectly unacceptable."

On the other hand, Dr. Donald Symons, a professor of anthropology at the University of California at Santa Barbara who studies human sexuality from an evolutionary perspective, said it was important to challenge the view that rape had little to do with sexuality. Though he quibbled with some points in the book, he said, "This is an argument for a particular view of male sexuality and it's a view that I think is correct."

Darwinian theory is based on the observation that evolution selects for success: animals with traits that promote survival or reproduction pass on their genes; others die out. Scientists have found an evolutionary view of animal behavior to be a powerful tool. But evolutionary psychologists are now seeking to apply similar principles to all aspects of human behavior. In some cases, scientists say, these efforts have proven fruitful.

But critics have argued that in wading into the complexities of modern human sexual relationships, scientists are on much shakier ground, often ignoring the powerful influences of culture.

At the core of the debate are assertions that are touchstones for evolutionary psychologists: that evolution favored promiscuity in men but choosiness in women and that the male of the species evolved to prefer young women because they are more likely to bear children.

Sexual coercion, Thornhill and Palmer argue, may have evolved as an alternative reproductive strategy for males who, for some reason, were not lucky enough to persuade a female to copulate voluntarily. Or it may have developed as simply a by-product of other adaptive traits, for example, a greater desire to engage multiple sex partners.

Rape is inexcusable, they argue, but it must be viewed as a "natural biological phenomenon," as much a part of nature as other undesirable happenings like thunderstorms, epidemics and tornadoes. Thornhill and Palmer marshall an assortment of evidence. They note that young women at the peak of their childbearing years are greatly overrepresented among rape victims and that rape leads to murder in only one-hundredth of 1 percent of the cases, a figure confirmed by other rape researchers.

They also note that sexual coercion of females by males occurs in many other animals, including the scorpion fly, an insect Thornhill has studied extensively. Sexual coercion has also been observed among fish, birds and nonhuman primates, notably the orangutan.

Critics, however, some of whom have followed the researchers' writings on rape over the years and others who read the excerpt in The Sciences, said they do not find these arguments convincing.

"We can't ask a female fish whether she appears to resist because she doesn't want to copulate or because she is testing males for their fitness," Coyne said. "But we can ask a human female who has been raped if she participated willingly."