Does Rape Have an Evolutionary Basis?

Abstract

Within the last thirty years, feminist theories investigaing the determinants of human behaviour have been challenged by the controversial development of evolutionary biology. Evolutionary biologists have proposed that human rape evolved as either an adaptive trait or a by-product of natural selection whereas feminist theories view rape as an symptom of societies' patriarchal heritage. This essay provides a comparison of evolutionary and feminist perspectives on rape and critiques Thornhill and Palmers thesis by discussing their flawed methodologies, non-representative sample populations and lack of supportive evidence to defend their theory. A biosocial theory of rape which considers the implications of male sex hormones on behaviour whilst retaining certain elements from other rape theories, is proposed as a superior alternative to evolutionary biology explanations of rape.

Does rape have an evolutionary basis?

Within the last thirty years, a notable schism has developed between feminist and evolutionary theories pertaining to the determinants of human behaviour (Archer & Vaughan, 2001; Brown, 2000; Ellis, 1991; Palmer, 1991; Shields & Shields, 1983; Thornhill & Palmer, 2000; Vega, 2001). The disparity has become acute with the burgeoning evolutionary explanations of the basis of human rape (Archer & Vaughan, 2001; Palmer, 1991, 1992; Vega, 2001). Evolutionary theories propose that males have an innate reproductive tendency to breed with many females and in certain circumstances; rape may serve as a copulatory mechanism (Archer & Vaughan, 2001; Ellis, 1991; Thornhill & Palmer, 2000). Evolutionary theories such as those summarised by Thornhill and Palmers (2000), propose that rape is either an adaptive trait or a by-product of natural selection whereas feminist theories view rape as an symptom of societies' patriarchal heritage illustrated as an act of dominance and control (Ellis, 1991; Shields & Shields, 1983). This essay will initially outline Thornhill and Palmer's controversial thesis on rape and contrast this view with feminist perspectives (Araji, 2000; Archer & Vaughan, 2001; Burr, 2000; Palmer, 1991, 1992; Thornhill & Palmer, 2000; Vega, 2001). A review of Thornhill & Palmers (2000) thesis will follow focusing on their critically flawed methodologies, non-representative sample populations and their general lack of support data to defend their controversial findings (Araji, 2000; Archer & Vaughan, 2001; Barbara & Franke, 2002; Brown, 2000; Thornhill & Thornhill, 1990; Vega, 2001). This essay will argue that the current literature pertaining to an evolutionary perspective on rape is methodically flawed and thus findings should be treated cautiously and interpreted tenuously at best. A biosocial theory of rape, proposed by Ellis (1991) which considers the implications of male sex hormones on behaviour whilst retaining certain elements from other rape theories, will be proposed as a superior alternative to evolutionary biology explanations of rape.

Traditionally, social learning and feminist perspectives have dominated literature pertaining to the topic of human rape (Vega, 2001; Thornhill & Palmer, 2000). The increasing interest of evolutionary biologists in this sensitive field of research has challenged social science and feminist explanations of human behaviour (Archer & Vaughan, 2001; Thornhill & Thornhill, 1990; Vega, 2001). The premise of an evolutionary approach to rape is that even though it may be viewed as a horrendous and antisocial act, it is evolutionary adaptive, innate and sexually motivated (Archer & Vaughan, 2001; Shields & Shields, 1983; Thornhill & Thornhill, 1990; Vega, 2001). The evolution of a male rape is thought to of occurred in response to the evolution of sex differences between males and females e.g., females having a larger investment in offspring than males, which led to females being in control of when sex would take place (Araji, 2000). This shift of balance provided ideal conditions for the selection of rape for reproduction or coercion (Araji, 2000, Thornhill & Palmer, 2000). Evolutionary biologist Randy Thornhill and anthropologist Craig Palmer have published a robust amount of literature which provides a sociobiological account of rape and their position on rape is clearly stated: "We ferverently believe that, just as the leopard's spots and giraffe's elongated neck are the results of aeons of past Darwinian selection, so is rape" (Thornhill & Palmer, 2000, pg.31). Two ultimate explanations of rape are proposed by Thornhill and Palmer (2000) which are said to supersede proximate/ feminist theories; rape was selected as an adaptation to increase reproductive output or rape evolved as a by-product from another adaptive trait e.g., male aggression (Thornhill & Palmer, 2000). However neither Thornhill or Palmer agree or explicitly state which evolutionary explanation best describes the findings of their studies (Araji, 2000; Archer & Vaughan, 2001; Segal, 2001; Thornhill & Palmer, 2000). Thornhill and Palmer's provide evidence for rape being an adaptation from observations of scorpion flies (Thornhill & Palmer, 2000). They describe the male scorpion flies notal organ; a clamp like apparatus which appears to be designed specifically for rape when normal mating behaviour is unavailable (Thornhill & Palmer, 2000). Evolutionary perspectives of rape make several predictions relative to conditions, which may predispose males to rape; rape could provide a mechanism for reproduction or copulation for disadvantaged males e.g., those with low social status due to poor looks or lack of wealth. Rape may also have evolved to occur when the cost of rape is minimal e.g., when a female is alone (Thornhill & Palmer, 2000). Thornhill and Palmer conclude that rape prevention programmes should focus primarily on educating males about their evolved sexual impulses instead of focusing

on rape as a desire to control and dominate Thornhill & Palmer, 2000). According to Thorhill and Palmer (2000), rape prevention programmes are doomed to fail if they do not inform people that the true motivation behind rape is sex. Thornhill and Palmer (2000) believe that an evolutionary account of rape should be viewed as the preferred model for future research pertaining to the topic and that the insights provided by such a perspective should be incorporated into models of social policy.

Feminist theories of rape rest on the premise that rape should viewed not as a natural or biological act of sex but an act of control and domination (Barbara & Fanke, 2002; Brownmiller,