This blog post examines the scientific debate over whether rape is an evolutionary adaptation or a byproduct of sexual desire mechanisms.
Before beginning this blog post, I want to mention that this blog post cannot make value judgments about whether rape is ‘right’ or ‘wrong’. I believe science has no place in making value judgments about rape. Science can only determine the truth regarding whether the social phenomenon of rape is an adaptation, meaning it is inherent in human genes through some mechanism. It cannot make value judgments beyond that. What this blog post aims to do is compare the explanations from both sides regarding whether rape is adaptive or not. The key point to consider is not which explanation is more ethical, but rather which side’s explanation is more scientific. On this topic, there are two major opposing camps: the proponents, represented by evolutionary psychologists like Richard Dawkins (Clinton Richard Dawkins, 1941~), and the opponents, centered around Stephen Jay Gould (1944~2002).
First, examining the proponents’ argument: the statement ‘male rape behavior is an adaptation’ means that, in evolutionary history, rape helped males reproduce, so males were designed to occasionally rape. Their logic posits that males unable to reproduce through normal means used rape to spread their genes, leading to this adaptation. Men who occasionally raped, while facing potential consequences like exile from the tribe or a tarnished reputation if discovered in primitive societies, gained significant benefits if reproduction was successful, as they passed their genes to future generations. This is because the proponents state the purpose of rape is species reproduction. I believe this argument is flawed from the outset. Even in modern society, rape crimes persist. Despite the development of contraceptive devices and abortion, which negate the assurance of species propagation through rape, rape crimes continue to occur. The purpose of rape is not species propagation. Furthermore, even if species propagation occurred in the past, it cannot be said that evolution always proceeds in that direction. In other words, even if a man’s genes are passed on to future generations through rape, it cannot be guaranteed that a genetic mutation leading to rape has occurred. For adaptation and natural selection to occur, a mutation must first arise. Yet, arguments supporting rape as an adaptation fail to provide scientifically substantiated explanations for this information. Crucially, there is also no evidence anywhere that rape increases the probability of a male passing his genes to future generations. While the chance of producing offspring through rape may indeed rise, in the long term, the social punishment and stigma inflicted on a male if the rape fails drastically reduces the likelihood that he will pass his genes on to future generations. Engaging in rape while bearing this social risk burden not only fails to achieve the goal of species propagation, even if that were the objective, but paradoxically lowers the probability of achieving it. Furthermore, according to those who argue rape is adaptive, and if rape were indeed adaptive, a mechanism specialized for rape should be found in males. Insects, in fact, possess specialized bodily organs for rape. Male insects are said to have organs like claspers that cannot be used for consensual intercourse but are employed exclusively during rape. In such insects, rape could reasonably be considered to have evolved as an adaptation. However, no such physical organ has been found in humans, nor is any mechanism known that is exclusively utilized for rape. Gould’s side, opposing the idea of rape as an adaptation, is structured around refuting Richard Dawkins’ arguments. Although later in the book, Gould does mention ethical issues, it is regrettable that he strays from the point of attempting a scientific analysis. Unlike evolutionary psychologists who believe genes themselves determine an organism’s mechanisms, Gould argues that genes are merely units composing organisms and cannot make decisions independently. Evolution, he contends, still occurs through various variables. From this perspective, rape can be seen as arising comprehensively from diverse causes rather than being an adaptation itself. The ‘byproduct hypothesis’ is the primary explanation for this. The byproduct hypothesis posits that rape is a byproduct of the sexual desire mechanism humans developed through adaptation. This mechanism evolved to channel sexual desire within consensual relationships; it also functions during rape. However, this does not mean humans adapted to possess genes enabling rape. Humans have simply evolved by creating diverse mechanisms for various behaviors, and rape is a phenomenon that emerged as a byproduct in this process. This argument also explains the modern problem of rape, which the proponents previously failed to address. It suggests rape exists not for species reproduction, but merely as a misdirected form of sexual desire expression.
The primary argument of the affirmative side is that rape has evolved as an independent adaptation. However, since rape is not only an act unrelated to species reproduction but also has causes that can be explained in complex ways, it is difficult to definitively label rape as an adaptation. Rather, as Gould suggests, it is more accurate to view rape as a phenomenon arising from the byproducts of humans’ diverse mechanisms. Therefore, rape is not an adaptation.
