The crocodile’s tears

People are fascinated by criminals, especially clever criminals who have the ability to con others. The most vicious offenders are often the subjects of movies and true-crime books. Canadian Paul Bernardo, for example, kidnapped, raped, killed, and mutilated two teenage girls, was involved in the rape and death of his sister-in-law, and raped dozens of women in the late 1980's and early 1990's. His story has already been written in several books, and a movie about him and his wife was released in the spring of 2006. During his trial he received numerous love letters and marriage proposals from complete strangers. Famous criminals are often the inspiration for great literature. Robert Louis Stevenson, for example, is said to have based his story of Jekyll and Hyde on William Brodie. Brodie was a well-respected Deacon by day and a gambler, womanizer, and burglar by night. Our ready fascination for these offenders demands an explanation, but in this chapter I will focus on discussing a group of men who are often considered to be the worst criminals, psychopaths. I begin by describing the concept of psychopathy and showing how unique psychopaths are. Then I discuss the question of whether psychopathy is a mental disorder, and describe an alternative view of psychopathy

Behavioral genetics: The study of differences

Behavioural genetics is about partitioning the sources of individual differences in any trait that can be measured reliably. The fundamental question is how much of the observed variability in a given trait can be explained by the fact that people have different genes, and how much can be explained by the fact that people have been exposed to different environments

Psychopathy, adaptation, and disorder

In a recent study, we found a negative association between psychopathy and violence against genetic relatives. We interpreted this result as a form of nepotism and argued that it failed to support the hypothesis that psychopathy is a mental disorder, suggesting instead that it supports the hypothesis that psychopathy is an evolved life history strategy. This interpretation and subsequent arguments have been challenged in a number of ways. Here, we identify several misunderstandings regarding the harmful dysfunction definition of mental disorder as it applies to psychopathy and regarding the meaning of nepotism. Furthermore, we examine the evidence provided by our critics that psychopathy is associated with other disorders, and we offer a comment on their alternative model of psychopathy. We conclude that there remains little evidence that psychopathy is the product of dysfunctional mechanisms

The view from the cuckold: A review of S. M. Platek and T. K. Shackelford (Eds.), Female infidelity and paternal uncertainty: Evolutionary perspectives on male anti-cuckoldry tactics

Evolutionary Psychology is an open-access peer-reviewed journal. It is permissible to archive articles from this journal.A Review of Steven M. Platek and Todd K. Shackelford (Eds.), Female Infidelity and Paternal Uncertainty: Evolutionary Perspectives on Male Anti-Cuckoldry Tactics. Cambridge University Press: New York, 2006. 248 pp. US$ 55.00 ISBN 0-521-60734-5 (paperback)Ye

Nepotistic patterns of violent psychopathy: evidence for adaptation?

Psychopaths routinely disregard social norms by engaging in selfish, antisocial, often violent behavior. Commonly characterized as mentally disordered, recent evidence suggests that psychopaths are executing a well-functioning, if unscrupulous strategy that historically increased reproductive success at the expense of others. Natural selection ought to have favored strategies that spared close kin from harm, however, because actions affecting the fitness of genetic relatives contribute to an individual’s inclusive fitness. Conversely, there is evidence that mental disorders can disrupt psychological mechanisms designed to protect relatives. Thus, mental disorder and adaptation accounts of psychopathy generate opposing hypotheses: psychopathy should be associated with an increase in the victimization of kin in the former account but not in the latter. Contrary to the mental disorder hypothesis, we show here in a sample of 289 violent offenders that variation in psychopathy predicts a decrease in the genetic relatedness of victims to offenders; that is, psychopathy predicts an increased likelihood of harming non-relatives. Because nepotistic inhibition in violence may be caused by dispersal or kin discrimination, we examined the effects of psychopathy on (1) the dispersal of offenders and their kin and (2) sexual assault frequency (as a window on kin discrimination). Although psychopathy was negatively associated with coresidence with kin and positively associated with the commission of sexual assault, it remained negatively associated with the genetic relatedness of victims to offenders after removing cases of offenders who had coresided with kin and cases of sexual assault from the analyses. These results stand in contrast to models positing psychopathy as a pathology, and provide support for the hypothesis that psychopathy reflects an evolutionary strategy largely favoring the exploitation of non-relatives

The causes of rape: Understanding individual differences in the male propensity for sexual aggression

Abstract only.The Causes of Rape: Understanding Individual Differences in Male Propensity for Sexual Aggression examines why some men are prone to rape, offers probable causes for this inclination, and provides a comprehensive review of scientific studies of coercive sex.Ye

Agreement of Self-Reported and Genital Measures of Sexual Arousal in Men and Women: A Meta-Analysis

The assessment of sexual arousal in men and women informs theoretical studies of human sexuality and provides a method to assess and evaluate the treatment of sexual dysfunctions and paraphilias. Understanding measures of arousal is, therefore, paramount to further theoretical and practical advances in the study of human sexuality. In this meta-analysis, we review research to quantify the extent of agreement between self-reported and genital measures of sexual arousal, to determine if there is a gender difference in this agreement, and to identify theoretical and methodological moderators of subjective-genital agreement. We identified 132 peer- or academically-reviewed laboratory studies published between 1969 and 2007 reporting a correlation between self-reported and genital measures of sexual arousal, with total sample sizes of 2,505 women and 1,918 men. There was a statistically significant gender difference in the agreement between self-reported and genital measures, with men (r = .66) showing a greater degree of agreement than women (r = .26). Two methodological moderators of the gender difference in subjective-genital agreement were identified: stimulus variability and timing of the assessment of self-reported sexual arousal. The results have implications for assessment of sexual arousal, the nature of gender differences in sexual arousal, and models of sexual response

Review of the book Evolution, gender, and rape by C. Travis Brown (Ed.)

The original publication is available at www.springerlink.comEvolution, Gender, and Rape. Edited By Cheryl Brown Travis. MIT Press, Cambridge, Massachusetts, 2003, 472 pp., $62.00 (cloth);$24.95 (paperback). This book is a collection of 17 critiques of the recent book, A Natural History of Rape, by Thornhill, a biologist, and Palmer, an anthropologist.Ye

Do people differentially remember cheaters?

The original publication is available at www.springerlink.comThe evolution of reciprocal altruism probably involved the evolution of mechanisms to detect cheating and remember cheaters. In a well-known study, Mealey, Daood, and Krage (1996) observed that participants had enhanced memory for faces that had previously been associated with descriptions of acts of cheating. There were, however, problems with the descriptions that were used in that study. We sought to replicate and extend the findings of Mealey and colleagues by using more controlled descriptions and by examining the possibility of enhanced altruist recognition. We also examined whether individual differences in cheating tendencies were related to cheater and altruist recognition. In the first experiment, 164 undergraduates saw 40 faces that were paired with character descriptions representing the categories of cheater, trustworthy, altruist, or neutral, for individuals who had either low or high social status. One week later participants reported which faces they recognized from the previous week (among 80 faces). Overall, the results failed to replicate the findings of Mealey and her colleagues, as there was no enhanced memory for cheaters. In addition, there was no enhanced memory for altruists, and no effect of participants’ cheating tendencies. A second experiment using a slightly different methodology produced similar results, with some evidence for enhanced memory for altruists.Ye