This blog post explores the biological background from the perspective that rape may be an evolutionary adaptation rather than simply a crime.
『Darwin’s Table』 (by Jang Dae-ik) is a book compiling discussions among several prominent biologists on various topics. This essay will focus on the topic ‘Is Rape an Adaptation?’ found on pages 15-34 among the many subjects covered. First, what are the views of the various scholars and the author in the book on this topic?
First, let’s examine the arguments from those who consider rape an adaptation. Cosmides and Pinker argued that rape is an adaptive behavior selected by natural selection, enabling males to achieve greater reproductive success and spread their offspring more widely. They further argued that since this approach seeks to understand rape biologically and propose biological solutions, ethical standards should be set aside. In contrast, Coen and Gould criticized this view, stating that if rape were a natural selection adaptation for males struggling with mating, it would fail to explain rape of children, non-reproductive women, incestuous rape, and same-sex rape.
Regarding this, the author agrees with Cosmides and Pinker’s argument. However, they did not condone rape by categorizing it as an unavoidable trait. They cited obesity as an example: during the hunter-gatherer period, when humanity spent most of its time, calorie intake was extremely low relative to energy expenditure. Therefore, obesity was likely an advantageous state in an environment where fat was efficiently stored. This trait persists today due to long-term adaptation, leading to obesity. Yet everyone knows that with sufficient willpower, it can be overcome. Similarly, the author contends that even if rape is an adaptive behavior, it can be overcome with willpower.
Personally, I share this author’s view. In The Selfish Gene (Richard Dawkins), this topic is explained as follows: humans are slaves to their genes. When a human is judged incapable of reproducing normally and thus unlikely to spread their genes to the next generation, the genes drive that human to commit rape. Thus, rape is considered an adaptation encoded in the genes. This act of rape is an adaptation that favors the reproduction of the species. In certain environments, males disadvantaged in mating sought to achieve species reproduction through rape.
Opponents of this argument might first counter: how can we fundamentally know whether rape is an act for reproduction or merely for pleasure? In my view, the pleasure derived from sexual intercourse and the urge to reproduce are not significantly different. For millennia, humans have experienced pleasure accompanying reproductive acts. Consequently, the distinction between the two has become indistinguishable.
Another anticipated counterargument concerns how to explain rape of non-reproductive individuals (such as same-sex partners, children, or women outside their reproductive years), as described by scholars above. To answer this, first, it is a mutation that arose during the long process of evolution and adaptation. Almost all organisms, over long evolutionary periods, have mutations that differ from other organisms in certain traits. Similarly, the reproductive urge or pleasure may have formed differently for some individuals compared to most people. Second, as explained above, the blurred distinction between reproductive desire and pleasure may have led to such unfortunate incidents, as individuals simply pursued that pleasure in their surroundings.
Third, one might question whether rape itself actually increases reproductive probability and is thus effective for species propagation. Indeed, it is said that during rape, changes occur in sperm shape, motility, and volume. This actually increases the probability of pregnancy by nearly double. Therefore, in ancient times without contraceptive devices, reproduction rates would have been higher. Thus, this increases an individual’s reproductive potential, and collectively, this also increases the species’ overall reproductive probability.
A woman’s pregnancy period is about 10 months, which is not a short period compared to her fertile window. Therefore, the number of offspring a woman can bear is not very large. Considering that the perpetrators of rape are mostly males at a disadvantage within the species, it follows that offspring from them would inherit these disadvantageous traits. Thus, from the perspective of reproductive quality, one could argue that rape is a disadvantageous trait that is not adaptive. Viewed this way, rape appears to be a form detrimental to species reproduction. However, the unconscious desire to achieve reproduction through rape originates from the individual. Individuals possess an instinct to perpetuate their lineage. It is my personal view that the accumulation of these individual desires leads to species reproduction. Furthermore, since it is unknown whether the disadvantageous traits are dominant, recessive, or polygenic, they likely do not significantly impact the maintenance of the species.
Finally, there is counterargument stemming from a fundamental difference in views on adaptation. Some argue that rape is not a product of natural selection but a byproduct of heightened sexual desire. Here, we must examine the meaning of the word ‘adaptation’. Traits advantageous for survival in a given environment are passed down, becoming characteristic features of the species over generations. This product of natural selection is termed adaptation. As mentioned earlier, rape is an extreme method chosen by males at a reproductive disadvantage. Furthermore, genes that recognize this as advantageous record it, using that record when conditions become unfavorable again. Based on this reasoning, rape is closer to an adaptation designed to increase reproductive probability than a mere byproduct of sexual desire.
In conclusion, I believe rape is an extreme method chosen by males at a reproductive disadvantage, etched into genes as a form of adaptation. Of course, bridging the gap with opposing views criticizing this as merely a byproduct of sexual desire seems difficult. However, using the most fundamental definition of adaptation, I have concluded it leans toward being an adaptation. Stepping away from ethical debates and viewing rape behavior from a biological perspective that understands it as an adaptation, it is something inscribed in the male genome. However, this does not mean it must necessarily be so or that it should be justified. As with the example of obesity, one can sufficiently avoid the situation with the will to resist. I wonder if approaching and attempting to resolve rape behavior from a biological perspective might lead to a new phase and discover innovative solutions.
