A Natural History of Rape

From Wikipedia, the free encyclopedia
Jump to: navigation, search
A Natural History of Rape: Biological Bases of Sexual Coercion
A Natural History of Rape.JPG
Cover of the first edition
Author Randy Thornhill, Craig T. Palmer
Country United States
Language English
Subject Rape
Published 2000 (The MIT Press)
Media type Print (hardcover and paperback)
Pages 251
ISBN 0-262-20125-9

A Natural History of Rape: Biological Bases of Sexual Coercion is a 2000 book about rape by biologist Randy Thornhill and anthropologist Craig T. Palmer, in which they propose that rape should be understood through evolutionary psychology,[1] and criticize the argument, popularized by Susan Brownmiller in Against Our Will, that rape is not sexually motivated.[2] Thornhill and Palmer argue that the capacity for rape is either an adaptation or a byproduct of adaptative traits such as sexual desire and aggressiveness.[1] The book received extensive criticism.


Thornhill and Palmer suggest that theory and research in evolutionary biology and evolutionary psychology can help to elucidate the ultimate (evolutionary) causes (as opposed to primarily proximate causes) of rape by males in different species, including humans.[2] They argue that the capacity for rape is either an adaptation, or, a byproduct of adaptative traits such as sexual desire and aggressiveness that have evolved for reasons that have no direct connection with the benefits or costs of rape.[1]

Thornhill and Palmer write that anthropologist Donald Symons was the first author to propose, in The Evolution of Human Sexuality (1979), that rape is "a by-product of adaptations designed for attaining sexual access to consenting partners." They note that Symons has falsely been accused of basing his arguments on the assumption that "behavior is genetically determined", even though he explicitly rejects that assumption and criticizes it at length.[3] Thornhill and Palmer criticize Susan Brownmiller's book Against Our Will, which popularized the view that rape is an expression of male domination that is not sexually motivated. They criticize arguments that rape is not sexually motivated on several grounds.[2] In their view, concluding that rape must be motivated by the desire to commit acts of violence is as illogical as concluding that men who pay prostitutes for sex are motivated by charity.[1]


Thornhill and Palmer's hypothesis is controversial.[4] The authors have claimed that some of the criticism it has received consists of straw man arguments, contradictions, and flawed logic.[5]

Psychology professor Frans de Waal argues that rape involves both sex and violence, and that while A Natural History of Rape serves as a corrective to the dogmatic view that rape is primarily about power, its view that rape is primarily sexually motivated is equally dogmatic. In de Waal's view, Thornhill and Palmer's theory could only be true if men who rape differ genetically from men who do not rape and sire more children than they could without committing rape, and there is no evidence that either of these things is true. He questions why one-third of rape victims are young children and the elderly, too young or too old to reproduce, if rape is about reproduction and why most men do not rape if rape is a smart reproductive strategy. He believes Thornhill and Palmer wrongly describe premature ejaculation and the ability to detect female vulnerability as rape adaptations, when other explanations for them exist.[6]

Evolution, Gender, and Rape, a 2003 book written in response to A Natural History of Rape, compiles the views of twenty-eight scholars opposed to sociobiological theories of rape. One contributor, Michael Kimmel, criticizes Thornhill and Palmer's argument that female rape victims tend to be sexually attractive young women, rather than children or older women, contrary to what would be expected if rapists selected victims based on inability to resist. Kimmel argues that younger women are the least likely to be married and the most likely to be out on dates with men, and therefore are the most likely to be raped because of opportunity arising from social exposure and marital status.[7] Palmer and Thornhill responded in an article in the journal Evolutionary Psychology.[8]

Smith et al. (2001) criticized Thornhill and Palmer's hypothesis that a predisposition to rape in certain circumstances is an evolved psychological adaptation. They developed a fitness cost/benefit mathematical model and populated it with estimates of certain parameters (some parameter estimates were based on studies of the Aché in Paraguay). Their model suggested that generally that only men with a future reproductive value of 1/10th or less of a typical 25-year-old man would have a net positive cost/benefit fitness ratio from committing rape. On the basis of their model and parameter estimates, they suggested that this would make it unlikely that rape generally would have net fitness benefits for most men.[9][10]

Wilson et al. (2003) argue that Thornhill and Palmer use the naturalistic fallacy inappropriately to forestall legitimate discussion about the ethical implications of their theory. According to Thornhill and Palmer, a naturalistic fallacy is to infer ethical conclusions (e.g., rape is good) from (true or false) statements of fact (e.g., rape is natural). Wilson et al. point out that combining a factual statement with an ethical statement to derive an ethical conclusion is standard ethical reasoning, not a naturalistic fallacy, because the moral judgment is not deduced exclusively from the factual statement. They further argue that if one combines Thornhill and Palmer's factual premise that rape increases the fitness of a woman's offspring with the ethical premise that it is right to increase fitness of offspring, the resulting deductively valid conclusion is that rape has also positive effects and that its ethical status is ambiguous. Wilson et al. state that Thornhill and Palmer dismiss all ethical objections with the phrase 'naturalistic fallacy' although "it is Thornhill and Palmer who are thinking fallaciously by using the naturalistic fallacy in this way."[11]

Hamilton (2008) has criticized Thornhill and Palmer's definition of rape as the coerced vaginal penetration of women of reproductive age. He has suggested that the exclusion of male rape, rape on women outside the reproductive age range, murderous rape, and non-vaginal forms of rape virtually guaranteed the confirmation of their hypothesis that rape is an evolved reproductive strategy and not a crime of violence.[12]

See also[edit]


  1. ^ a b c d LeVay, Simon; Baldwin, Janice (2009). Human Sexuality, Third edition. Sinauer Associates, Inc. pp. 598, 602. ISBN 978-0-87893-424-9. 
  2. ^ a b c Thornhill, Randy & Palmer, Craig T. A Natural History of Rape: Biological Bases of Sexual Coercion. The MIT Press, 2000, pp. 126, 133-135, 138-139.
  3. ^ Thornhill, Randy & Palmer, Craig T. A Natural History of Rape: Biological Bases of Sexual Coercion. The MIT Press, 2000, pp. 61, 110, 111.
  4. ^ Coyne, Jerry; Berry, Andrew (9 March 2000). "Rape as an adaptation". Nature 404 (6774): 121–122. doi:10.1038/35004636. 
  5. ^ Palmer, Craig T.; Thornhill, Randy (2003). "Straw men and fairy tales: Evaluating reactions to a natural history of rape". Journal of Sex Research 40 (3): 249–255. doi:10.1080/00224490309552189. 
  6. ^ de Waal, Frans B. M. (April 2, 2000). "Survival of the Rapist". The New York Times. Retrieved March 27, 2013. 
  7. ^ Kimmel, Michael (2003). "An Unnatural History of Rape". In Travis, Cheryl Brown. Evolution, Gender, and Rape. MIT Press. pp. 221–233. ISBN 0-262-20143-7. 
  8. ^ Palmer, Craig T.; Thornhill, Randy (2003). "A posse of good citizens bring outlaw evolutionists to justice" (PDF). Evolutionary Psychology 1, p. 10-27. 
  9. ^ Why Do We Rape, Kill and Sleep Around?, Sharon Begley, The Daily Beast
  10. ^ Smith, Eric; Mulde, Monique; Hill, Kim (2001). "Controversies in the evolutionary social sciences: a guide for the perplexed" (PDF). Trends in Ecology and Evolution 16 (3): 128–135. doi:10.1016/s0169-5347(00)02077-2. Retrieved July 1, 2013. 
  11. ^ Wilson, David Sloan; Dietrich, Eric; Clark, Anne B. (2003). "On the inappropriate use of the naturalistic fallacy in evolutionary psychology" (PDF). Biology and Philosophy 18 (5): 669–681. doi:10.1023/A:1026380825208. Retrieved March 23, 2013. 
  12. ^ Hamilton, Richard (2008). "The Darwinian cage: Evolutionary psychology as moral science". Theory Culture and Society 25 (2): 105–125. doi:10.1177/0263276407086793. Retrieved March 30, 2013. 

External links[edit]