In this blog post, I examine the debate over whether rape is the result of evolutionary adaptation from the perspective of anti-adaptationists.
Since the publication of Thornhill’s ‘The Natural History of Rape’, a heated debate has raged over the question, “Is rape an adaptation?” To answer this question, we must first define the concept of “adaptation.” According to ‘Darwin’s Table’, adaptation refers to the process by which an organism changes over a long period of time in a direction that is suited to its environment. Evolution through such adaptation is a concept accepted by most biologists. However, there are still diverse views on whether the human mind and behavior are entirely the products of adaptation or byproducts of other evolutionary processes. Since rape is also a form of human behavior, scholars are broadly divided into adaptationists, who argue that “rape is an adaptation,” and anti-adaptationists, who argue that “rape is not an adaptation.” I believe the anti-adaptationists’ claim that “rape is not an adaptation” is more persuasive than the adaptationists’ claim that “rape is an adaptation.” The reasons are as follows.
To determine whether rape is an adaptation, we must examine—based on the definition of adaptation discussed earlier—whether rape has evolved as a result of changes that make it suitable for the environment. Changing in a direction suitable for the environment can ultimately be seen as a direction that aids an individual’s survival or reproduction. However, I find it difficult to view rape as providing any substantial benefit to survival or reproduction. First, considering cases such as male-on-male rape, incest, or the rape of children, it is hard to regard rape as a behavior that necessarily aids survival or reproduction. This is because, if rape were the result of an adaptation for reproduction, such instances of rape—which are not directly related to reproduction—should occur very rarely. Furthermore, even in cases where a man rapes a woman, as Coin noted in ‘Darwin’s Table’, the perpetrators do not commit the crime with the intention of “impregnating this woman today through rape so she will bear my child.” If rape were the result of an adaptation for male reproduction, such behavior would have to be carried out with reproduction as its purpose. However, in reality, it is difficult to view such cases as generally motivated by that intention, and the causes of rape cannot be explained by reproduction alone.
Adaptationists counter this argument as follows: It may not be true that men commit rape while directly conscious of reproduction. However, rape can provide reproductive opportunities for some men who have difficulty finding a mate, and consequently, it can help them pass on their genes to their offspring. Furthermore, while cases of men raping other men, or of incest or child rape, do exist, their frequency is far lower than that of rape targeting women of childbearing age; therefore, they argue that one cannot conclude that rape is not an adaptation based solely on these exceptional cases.
However, I believe that these counterarguments by adaptationists lack sufficient evidence. Adaptationists argue that rape aids reproduction because it allows men who have failed to secure a mate to leave behind their own offspring. However, there are several problems with this argument. First, even if pregnancy results from rape, it does not necessarily lead to childbirth. In modern society, there are countries and regions where abortion is legal, and there are cases where the victim chooses not to continue the pregnancy; therefore, it is difficult to conclude that rape directly aids reproduction. Furthermore, even if rape were to increase a man’s reproductive prospects in some cases, it clearly causes harm to women. Women who become pregnant as a result of rape may face significant physical and mental strain due to pregnancy, childbirth, and child-rearing, and they face major restrictions on their choice of a partner and their reproductive plans. Therefore, from a woman’s perspective, rape cannot be viewed as a behavior that aids reproduction. Ultimately, even if rape might have a certain impact on the reproduction of some men, this is an argument limited to the male perspective, and it is difficult to view the act of rape as a whole as an adaptation that benefits human reproduction.
Adaptationists refute this point as well. While it is true that abortion in modern society reduces the number of births resulting from rape, abortion technology is a very recent development in the context of human evolutionary history. Since adaptation is a process that occurs over a long period of time, it is argued that it is inappropriate to conclude that rape is not an adaptation based on relatively recent medical technology. Furthermore, they argue that if male rape had a detrimental effect on female reproduction, women would likely have adapted in ways that reduce the risk of rape. In other words, because rape had a negative impact on women’s reproductive success, traits that allowed them to avoid or defend against it may have been selected, and this, too, can be interpreted as a form of adaptation.
As such, regarding whether rape is the result of an adaptation that aids survival or reproduction, adaptationists and anti-adaptationists each present their own arguments. However, even in modern evolutionary psychology and evolutionary biology, this issue remains a field of research where various hypotheses compete, rather than one with an established conclusion. From the anti-adaptationist perspective examined by the author, there are still many questions regarding the extent to which rape has actually contributed to male reproductive success. Furthermore, even if rape were to have had the effect of increasing men’s reproductive success in certain situations, considering that it simultaneously inflicts immense harm on women and has a negative impact on reproduction, it is difficult to view it as an adaptation beneficial to human reproduction as a whole. Therefore, I believe the anti-adaptationist claim that “rape is not an adaptation” is more persuasive than the claim that “rape is an adaptation.”
