Do scientific theories affect men's evaluations of sex crimes?

Abstract

Evolutionary psychology accounts of gender differences in sexual behaviors in general and men's sexual aggression, in particular, has been criticized for legitimizing males' sexual misconduct. To empirically assess such critiques, two studies examined how men's judgments of male sex crimes (solicitation of sex from a prostitute; rape) are influenced by exposure to (a) evolutionary psychological theories and (b) social-constructivist theories. Across two studies, a consistent pattern emerged compared with a control condition (a) exposure to evolutionary psychology theories had no observable impact on male judgments of men's criminal sexual behavior, whereas (b) exposure to social-constructivist theories did affect judgments, leading men to evaluate sex crimes more harshly. Additional results (from Study 2) indicate that this effect is mediated by perceptions of male control over sexual urges. These results have implications for journalists, educators, and scientists. Aggr. Behav. 37:440-449, 2011. © 2011 Wiley-Liss, Inc.

Full text

AGGRESSIVE BEHAVIOR
Volume 37, pages 440–449 (2011)
Do Scientific Theories Affect Men’s Evaluations
of Sex Crimes?
Ilan Dar-Nimrod
1!
, Steven J. Heine
2
, Benjamin Y. Cheung
2
, and Mark Schaller
2
1
University of Rochester, Rochester, New York
2
University of British Columbia, British Columbia
:::::::::::::::::::::::::::::::::::::::::
Evolutionary psychology accounts of gender differences in sexual behaviors in general and men’s sexual aggression, in particular, has
been criticized for legitimizing males’ sexual misconduct. To empirically assess such critiques, two studies examined how men’s
judgments of male sex crimes (solicitation of sex from a prostitute; rape) are influenced by exposure to (a) evolutionary psychological
theories and (b) social-constructivist theories. Across two studies, a consistent pattern emerged compared with a control condition
(a) exposure to evolutionary psychology theories had no observable impact on male judgments of men’s criminal sexual behavior,
whereas (b) exposure to social-constructivist theories did affect judgments, leading men to evaluate sex crimes more harshly.
Additional results (from Study 2) indicate that this effect is mediated by perceptions of male control over sexual urges. These results
have implications for journalists, educators, and scientists. Aggr. Behav. 37:440–449, 2011.
r
2011 Wiley-Liss, Inc.
:::::::::::::::::::::::::::::::::::::::::
Keywords: psychological essentialism; genetic; evolutionary psychology; sexual behavior; crime
INTRODUCTION
Few theories in science have attracted as much
controversy as evolutionary psychological accounts
of human behavior. The controversy focuses not
merely on the scientific merit of the competing
explanations, but on their moral implications
[Buller, 2005; Nelkin and Lindee, 1995]. Further-
more, this controversy extends beyond academia as
popular media outlets have also joined the discus-
sion, which suggests that the public has a great deal
of interest in this topic as well. This is especially
evident in the domain of sexual behaviors.
For example, a recent article in Newsweek magazine
summarized some of the common criticisms lodged
against evolutionary psychology [Begley, 2009]—
including the argument that evolutionary psycho-
logical theories may be used by men as a sort of
‘‘get-out-of-jail-free card’’ to justify and excuse
criminal sexual behaviors such as rape.
This criticism raises an important question with
broad theoretical ramifications and important prac-
tical implications that has yet to be tested empirically.
Does exposure to evolutionary accounts for sexual
behavior lead men to think differently about male
sexual misbehavior? Research across a broad array of
life domains suggests that highlighting arguments of
genetics can influence the ways that people think
about and act in those domains [for a review see
Dar-Nimrod and Heine, 2011]. In this article, we test
the question whether exposure to different scientific
theories for sexual behavior (specifically, theories that
draw on evolutionary-genetic and social-constructi-
vist perspectives) lead men to evaluate and punish
sexual perpetrators differently.
Such research has an immediate applied angle,
as criminality-related genetic research findings have
already been addressed in the US courts [Bernet
et al., 2007]. Criminal responsibility is closely
evaluated based on criminal intention, choice, and
the ability to control one’s actions. Jurors and
judges routinely evaluate these components before
making judicial decisions. Thus, elements that affect
perceptions of control are central in such decisions.
Perceived fatalistic relationships between genes and
unlawful behaviors diminish the perceived volition
of an accused. For example, Cooper Dreyfuss and
Published online 15 June 2011 in Wiley Online Library (wiley
onlinelibrary.com). DOI: 10.1002/ab.20401
Received 17 November 2010; Revised 11 May 2011; Accepted 11
May 2011
!
Correspondence to: Ilan Dar-Nimrod, School of Medicine and
Dentistry, University of Rochester, 601 Elmwood Avenue, Box
PSYCH, Rochester, NY 14642.
E-mail: ilan_dar-nimrod@urmc.rochester.edu
r
2011 Wiley-Liss, Inc.

Nelkin [1992] discussed two separate cases in which
the California Supreme Court considered whether
to disbar attorneys who embezzled clients’ funds. In
neither case did the defendants contest the allegations,
and in both cases the defendants identified alcohol
abuse as the proximal cause of their misconduct.
However, in one of the cases, the defendant cited
evidence pertaining to genetic predisposition for
alcoholism. This defendant was allowed to continue
practicing, whereas the other defendant—the attorney
who did not cite evidence of genetic predisposition—
was disbarred [Cooper Dreyfuss and Nelkin, [1992,
p 328]. Other cases similarly suggest that genetic
arguments may result in more lenient legal judgments
[Feresin, 2009; R. vs. Luedecke, 2005].
A nascent research line suggests that attribution of
unlawful behaviors to certain genetic conditions
can affect the perception of the culpability of the
actor. Monterosso et al. [2005] asked participants
to evaluate vignettes describing criminal behaviors
(e.g. murder) in which the perceived cause of the
behavior was either biological or experiential.
Offering experiential causes (e.g. the protagonist
had a history of abuse), rather than biological causes
(e.g. the protagonist had an inherited biological
condition), led the participants to evaluate the
behaviors as more voluntary and blameworthy, the
protagonists attracted less sympathy, and were
assigned more severe punishment [see also Phelan,
2005]. The current research extends this investiga-
tion to address critical claims with regard to
evolutionary psychology and sex crimes.
EVOLUTIONARY AND SOCIAL-CONSTRUCTIVIST
PERSPECTIVES ON MALE SEXUAL BEHAVIOR
There is little dispute that there are gender
differences in mate selection strategies within Western
society. Empirical research clearly indicates that men
are more likely to desire multiple short-term mating
relationships [for a review see Baumeister et al., 2001]
and to display sexual aggression. These sex differ-
ences are accepted within both the evolutionary
psychology literature [e.g. Allgeier and Wiederman,
1994; Buss, 2007] and the social-constructivism
literature [e.g. Travis, 1999; White et al., 2000].
However, these two perspectives explain sex differ-
ences in mate selection strategies in divergent ways.
Evolutionary psychological theories focus on the
implications of behavioral strategies for reproductive
fitness (i.e. reproduction of genes) and argue that, in
ancestral populations, male and female reproductive
fitness was linked to somewhat different behavioral
strategies, with genetic consequences that manifest in
the mental circuitry of contemporary human popula-
tions. In contrast, social-constructivist theories
focus not on the biological bases of human behavior,
but instead on contemporary social forces, power
relationships, and cultural practices that may give rise
to the same phenomena.
Evolutionary accounts of sex differences in sexual
behavior have been not only generative and
influential but also controversial. Some critiques of
evolutionary psychological theories have focused
primarily on the science itself [e.g. Wood and Eagly,
2002]. Other critiques have focused less on the
science and more on the perceived moral implica-
tions. For example, Nelkin [2000] suggested that
‘‘Evolutionary psychology is not only a new science,
it is a vision of morality and social order, a guide to
moral behavior and policy agendas’’ (p 24). Such
critiques suggest that evolutionary explanations for
human behavior may be employed by individuals
(consciously or not) as justification for undesirable
behaviors [e.g. Kimmel, 2003; Rose, 2000].
Although evolutionary psychology focuses on
purported adaptations that emerged in the ancestral
environment as the source of its predictions, social
constructivist theories focus on social and cultural
elements. This school of thought typically rejects the
assertion that psychological categories, such as
gender, exist apart from the context in which they
occur or are studied [e.g. Hare-Mustin and Marecek,
1990]. Within the social-constructivist tradition,
different elements of the sociocultural context are
identified as contributing to gender differences and
mating strategies. These theories therefore highlight
the diversity and malleability of sexual behavior.
For many empirical scientists, a social constructivist
perspective may appear unscientific because ‘‘its
views are sometimes difficult to convey to those
trained in a more positivist tradition’’ [Unger, 2001,
p 264]. However, for people (including most lay-
people) who are unconstrained by a positivist
tradition, social-constructivist theories often provide
appealing explanations for sex differences in sexual
behavior.
GENETIC ESSENTIALISM IN PERCEPTIONS
OF SEX-RELEVANT BEHAVIOR
To what extent might exposure to evolutionary
vs. social-constructivist explanations influence
laypeople’s thoughts and behavior? Dar-Nimrod
and Heine [2011] argued that individuals’ intuitive
understanding of the influence of genetic factors on
441Scientific Theories and Sex Crimes
Aggr. Behav.

behavior (which lies at the center of evolutionary
theorizing, but not social-constructivist theorizing)
is shaped by a cognitive bias: genetic essentialism.
Research on psychological essentialism demon-
strates that people perceive ‘‘natural’’ categories—
such as living organisms—as having an underlying,
definitive, and unseen nature that makes them what
they are [e.g. Gelman, 2003; Medin and Ortony,
1989; Rothbart and Taylor, 1992]. Psychological
essentialism appears to be a prevalent cognitive bias,
and has been identified among children and adults
across a wide range of cultures [Astuti et al., 2004;
Gelman, 2003; Gil-White, 2001; Sousa et al., 2002].
Across these contexts, people show a robust
tendency to judge category membership as reflecting
an immutable underlying essence. The concept of
essence is psychologically abstract, and so it has
been proposed that people use some sort of ‘‘essence
placeholder’’ [Medin and Ortony, 1989, p 184–185]
as a surrogate for the unobservable essence. Dar-
Nimrod and Heine [2011] argued that in contem-
porary societies, the concept of genes is frequently
used as the placeholder for this essence. A growing
literature has begun to examine implications of this
genetic essentialism—including implications for
exposure to different kinds of scientific explanations
(i.e. those that emphasize genetic vs. sociocultural
processes) have on individuals’ attitudes and
behaviors [Brescoll and LaFrance, 2004; Coleman
and Hong, 2008; Dar-Nimrod and Heine, 2006;
Monterosso et al., 2005; Williams and Eberhardt,
2008; for a review see Dar-Nimrod and Heine, 2011].
Many of these studies have focused on scientific
explanations for sex differences.
Sex is an especially essentialized social category
[e.g. Gelman and Taylor, 2000; Haslam et al., 2000;
Prentice and Miller, 2006]. One implication is that
people may naturally assume a genetic basis for sex
differences and sex-relevant behavior. If so, then
exposure to genetic explanations for such behaviors
(which merely resonate with their default essentialist
assumptions) may have little or no influence on
subsequent cognitions and behavior, whereas expo-
sure to sociocultural explanations (which undermine
their default assumptions) may actually change
beliefs and behaviors. Exactly such a pattern of
results was reported by Dar-Nimrod and Heine
[2006]. Across two studies, women were exposed to a
bogus explanation for men’s alleged superiority in
mathematics, and then took a math test themselves.
Women who were exposed to a genetic explanation
performed no better or worser on the subsequent
math test than women who reflected on their gender
(the control condition). However, women who were
exposed to a sociocultural explanation for sex
differences actually performed better, compared
with both the control and the genetic explanation
condition.
Although the studies by Dar-Nimrod and Heine
[2006] imply that people assume a genetic basis for
sex differences in the domain of academic perfor-
mance, other research suggests that default assump-
tions may vary depending on the specific domain or
context. For example, Brescoll and LaFrance [2004]
presented participants with fictitious newspaper
articles claiming that the ability to identify plants
varied according to sex. These articles differed in the
explanation they offered for this variation: in one
condition, the article provided a genetic explanation,
whereas in another condition, it provided a socio-
cultural explanation. There was also a control
condition. The researchers found that exposure to
a genetic explanation for sex differences in plant
identification increased beliefs that a person cannot
change and also inspired stronger endorsement of
gender stereotypes, compared with the sociocultural
explanation condition. Additional results revealed
that under some circumstances, exposure to a
genetic account produced results that differed from
both the sociocultural explanation condition and
the control condition (which produced equivalent
results), but under other circumstances exposure to
a sociocultural explanation produced results that
differed from both the genetic explanation condi-
tion and the control condition (which produced
equivalent results). These patterns of results suggest
that, while there may be a general tendency to
assume that some genetic essence underlies sex
differences and sex-relevant behavior, this general
tendency may be somewhat variable, depending on
the specific context.
OVERVIEW OF EXPERIMENTS
Although prior research has examined the impact
of genetic explanations on attitudes and behaviors,
no prior work in this area has examined the
influence of evolutionary explanations—which con-
stitute the specific target of some of the most-heated
controversies in the social sciences. The two experi-
ments reported below extend the test of genetic
essentialism to include evolutionary psychology
theories. To our knowledge, they also provide the
first empirical evidence testing a claim that is often
made by critics of evolutionary psychology: do
evolutionary explanations actually induce men to be
more tolerant of sex crimes?
442 Dar-Nimrod et al.
Aggr. Behav.

Two studies assessed responses to men who had
committed sex crimes. We focus on men as they
are overrepresented in sexual violence, and the
controversy regarding evolutionary psychological
accounts has largely been centered on concerns
about how men might respond to these accounts.
Both experiments included a manipulation: in one
condition, participants were exposed to an evolu-
tionary theory for a relevant sexual behavior. In a
second condition, participants were exposed to a
social-constructivist explanation for that behavior.
A third condition served as a control, allowing for
independent assessments of the potential impact
of evolutionary and social-constructivist theories.
Grounded in the genetic essentialism framework
[Dar-Nimrod and Heine, 2011], we hypothesized
that exposure to evolutionary etiological accounts
will lead to a reduction in negative evaluations and
punitive tendencies toward male perpetrators of
sexual crimes compared with exposure to social
constructivist etiological accounts. We included
control conditions in the studies to examine which
perspective seem to guide men’s default evaluations.
Study 1 examined the impact of this manipulation
on judgments of a man arrested for soliciting a
prostitute. Study 2 examined their impact of the
manipulation on judgments of a rapist.
Study 1
On the basis of the genetic essentialism framework
[Dar-Nimrod and Heine, 2011], we predicted the
following: compared with men who read a social
constructivist account for males’ preference for
short-term sexual encounters, men who read an
evolutionary account will be less punitive (set a
lower bail amount) toward a men who was caught
trying to solicit a prostitute (i.e. engage in a short
term sexual encounter), controlling for general
punitive tendencies (explicated from the amount of
bail set for a shoplifter). A control condition was
included to indicate which theories seem to be in line
with men’s default reactions.
Method. Fifty-eight men (18–67 year old,
Mage 522.86, SD 57.53) were recruited from
psychology classes at the University of British
Columbia. Following the method used in Dar-Nimrod
and Heine [2006], participants first completed what
was apparently a GRE-like verbal test that contained
two articles, purportedly assessing reading comprehen-
sion. One of these articles contained the manipulation.
(Disguising the manipulation in the context of a
GRE-like test served to reduce the likelihood that
participants would perceive a connection between the
manipulation and the dependent measures, and
thus helped to eliminate experimental demand as
aplausiblealternativeexplanationfordifferences
between conditions.)
In one condition, the article presented an evolu-
tionary explanation (based on differential parental
investment) for sex differences in mate selection
strategies and sexual behavior. It emphasized the
ancestral environment in the explanation. A repre-
sentative paragraph reads:
Following Darwin’s evolutionary theory, passing
ones genes to the next generation is the ultimate
(yet non-conscious) goal of an organism. The
best procreation strategy therefore is not sur-
prisingly very different between men and
women. Biologically speaking men would be
most successful in passing more of their genes to
the next generation by mating with as many
women as they can, minimizing their investment
in any individual woman. The law of large
numbers favours their chances and their share in
the next generation gene pool. Women, on the
other hand, are heavily invested in each child.
Historically they need the provision and protec-
tion of a man during the vulnerable time of child
rearing in which the child is completely depen-
dent. Women therefore, should be more selec-
tive in their choice of partners, searching for
those who would stick around and contribute
(resources, protection) to the development of the
child.
In a second condition, the article explained the same
phenomenon from a social-constructivist perspec-
tive. It emphasized societal gender inequality.
A representative paragraph reads:
The differing distributions of men and women
into social roles form the basis for the social
structural theory of sex differences. According
to the theory, greater power and status tend to
be associated with male-dominated roles: Men
are used to roles with greater power and status
which produce more dominant behavior, and
women’ are used to roles with lesser power and
status which produce more subordinate beha-
vior. Dominant behavior is controlling, asser-
tive, directive and autocratic, and involves
sexual control. Subordinate behavior is more
compliant to social influence, less aggressive,
more cooperative, and involves a lack of sexual
independence. The theory has been able to
demonstrate just how strong the ties between
social norms and sexual double standards are.
443Scientific Theories and Sex Crimes
Aggr. Behav.

In societies where women are more strongly
suppressed, promiscuous women are shunned
by the mainstream and in extreme cases they
may be ostracized. In societies where women
had made strides towards social equality, on
the other hand, women sexual promiscuity
(although on average is still frowned upon
more than men’s due to the yet to be achieved
goal of complete equality) is much more
accepted and promiscuous women can be
idolized and admired (e.g., Madonna, Paris
Hilton, Gwen Stephanie). However, most
societies are still unforgiving with regards to
sexual promiscuity, especially for women.
In the third (control) condition, the article discussed
obesity among pets. Immediately after the article,
participants were presented with four reading compre-
hension questions to ensure individuals’ exposure to
the manipulation.
Next, participants were presented with two bail-
setting tasks. For one task, participants set bail for a
woman who was arrested for shoplifting (this task
was included to reduce suspicion about the purposes
of the study and to control for general punitive
tendencies). The other task contained the measure of
primary conceptual interest: participants set bail for
a man (a ‘‘John’’) who was arrested after attempting
to solicit sexual services from an undercover police-
woman masquerading as a prostitute. The bail they
set was to be within the range of $50–$1,000.
(The full experimental materials for all studies are
available online at http://www.psych.ubc.ca/!heine/
sexcrimes.doc.) Following the experiment, parti-
cipants were fully debriefed with regard to the study
hypotheses.
Results and Discussion. Two participants
were removed from the data because of chance
performance on the reading comprehension ques-
tions suggesting that they had not read or under-
stood the manipulation. This left a final sample of
56 participants. (Two additional participants
reported some suspicion about the purpose of the
study. We report results that include these two parti-
cipants; effect sizes and statistical significance
remain virtually unchanged if suspicious parti-
cipants are excluded from analyses).
Bail judgments for the ‘‘John’’ were analyzed with
a single factor analysis of covariance, with the bail
set for the shoplifter as a covariate [which, as
expected, was not affected by the manipulation
(F(2, 53) 50.33, ns), but had a significant effect on
the dependent variable]. There was a manipulation
effect, F(2, 52) 53.89, Po.05, Z2
p5.13 (Fig. 1).
Fisher PLSD post hoc comparisons on the
estimated marginal means provided support to our
prediction indicating that men in the social-
constructivist condition (M5$461.65, SE 552.37)
set significantly higher bail relative to men in both the
evolutionary condition (M5$301.35, SE 553.64,
Po.05) and the control condition (M5$267.34,
SE 552.37, P5.01). The latter two conditions did
not differ significantly (P4.5). That is, men’s bail
judgments reveal that they appeared to be unaffected
by the evolutionary arguments, whereas they were
more punitive toward a ‘‘John’’ following a social-
constructivist argument.
This pattern of results suggests that among men,
the default theory for male sexual promiscuity
may be similar to that offered by the evolutionary
explanation that they encountered. Consequently,
the social-constructivist account appears to have
challenged their default theories, accounting for the
finding that men became more punitive toward the
John after encountering the social-constructivist
account. Alternatively, men might have given
harsher punishment to the John in the social-
constructivist condition because of social desirability
concerns. That is, because the social constructivist
account portrayed gender differences in mating
strategies as an outcome of gender inequality norms,
men might have wanted to distance themselves from
such norms. We address this question in Study 2,
which examined the impact of a similar manipula-
tion on evaluations of a man who committed rape.
Study 2
Rape is one of the most viscerally objectionable of
human behaviors, and an emotionally charged issue.
Much scholarly attention devoted to the origins of
rape falls under the aegis of the larger ‘‘nature vs.
nurture’’ debate. There are many different social-
constructivist accounts of rape [ Brownmiller, 1976;
100
200
300
400
500
600
Evolutionary Sociocultural Control
Condi tio n
Set bail for 'John'
Fig. 1. Amount of bail (in Canadian dollars) participants assign for the
release of a ‘‘John’’ after reading a scientific article.
444 Dar-Nimrod et al.
Aggr. Behav.

Burt, 1980; Martin, 2003]. These social-constructivist
explanations focus on a variety of cultural pheno-
mena that may play a role in predisposing men
toward rape, including language [Benedict, 2005],
power [Brownmiller, 1976], pornography [Dines,
2005], religion [Adams, 2005], social scripts [Levy,
2005], and even violence in sport [Messner, 2005]. The
common thread in all these accounts is the location of
the antecedents of rape in contemporary social and
cultural environments.
With the emergence of evolutionary psychology,
scholars began to introduce biological explanations
for the phenomenon [e.g. Barash, 1979]. This trend
culminated in the publication of Thornhill and
Palmer’s [2000] A Natural History of Rape:Biological
Bases of Sexual Coercion. Building on parental
investment theory and sexual selection theory,
Thornhill and Palmer speculated that rape may have
been adaptive in certain environments, or was a by-
product of other adaptations in the realm of male
sexual behavior.
Thornhill and Palmer’s [2000] book attracted
considerable controversy (see, for example, Travis
[2003], for an edited volume containing 17 critical
papers written in response). The criticism was not
confined to the scientific merit of Thornhill and
Palmer’s work. Many critiques echoed the ideological
complaints aroused by evolutionary explanations
for sexual behavior more generally. For example,
Roughgarden [2004, p 76] referred to Thornhill and
Palmer’s work as ‘‘the latest ‘‘evolution made me do
it’’ excuse for criminal behavior,’’ and Kimmel
[2003, p 221] argued that: ‘‘the book tells us less
about ‘‘the biological bases of sexual coercion’’ than
the fantasies of those who justify sexual coercion.
It’s bad science, bad history, and bad politics—or,
more accurately, it’s bad politics masqueraded as
science.’’
Does an evolutionary explanation for sexual
coercion induce men to justify and excuse the
behavior of rapists? And what impact might social-
constructivist accounts have on men’s perceptions of
rape and rapists? Study 2 addressed these questions.
We hypothesized that compared with men who
read a social constructivist account for rape, men
who read an evolutionary account will be: (1) less
critical of a date rape behavior, (2) less punitive
toward a sexual aggressor, and (3) perceive sexual
aggressors as having less control over their sexual
misbehaviors. In addition, we predicted that the
expected differences in men’s assessment of a sexual
aggressor’s behavior and the punishment they will
dole out will be, at least partially, mediated by
perceptions of control over sexual aggression.
Following the results from Study 1, we expected
men in the control condition to react similarly to
men in the evolutionary condition.
Method. At the University of British Columbia,
67 men (18–28 year old, Mage 519.93, SD 52.13)
were invited to take part in an experiment allegedly
designed for ‘‘evaluations of sexual content.’’ Upon
arrival, they were randomly assigned to one of three
experimental conditions. In each condition, they
read an article on sexual behavior, the content of
which varied across conditions.
In one condition, the article presented an evolu-
tionary explanation for rape (based on arguments
presented by Thornhill and Palmer [2000]).
A representative paragraph reads:
Although the concept of rape usually brings
upon an involuntary aversive reaction when
brought to mind, John Archer and his collea-
gues suggest that rape and associated aggres-
sive behaviors may be adaptive strategies that
lead to greater reproductive success in humans
and some animal species. According to their
research, sexual aggressiveness and forced
copulation increases the probability for males
to pass their genes to the next generation. This
implies that compared to less sexually aggres-
sive males, those that are able to copulate with
more women, sometimes through physical
force or deception, have a greater chance of
achieving the ultimate evolutionary goal – the
ability to pass on their genes. Thus rape may be
an adaptive strategy – a behavior that ensures
the continuation of our genetic makeup.
In a second condition, the article presented a social-
constructivist explanation for rape (suggesting that
rape results from societal norms that objectify women
for example). A representative paragraph reads:
Although honor cultures may explicitly
endorse male dominance that can bring about
violent and aggressive acts towards women,
even rape, other cultures may also be insinuating
the acceptance of violent behavior towards
women through their reinforcement of the
notion that women are subordinate to men.
Research done by Martha Burt suggests that
we live in a culture that facilitates rape through
acts that support the objectification of women
as well as violent and sexual transgressions
towards them through the media. For example,
it has been found that there is a direct
correlation between the rate of pornographic
magazine circulation and rape, suggesting that
445Scientific Theories and Sex Crimes
Aggr. Behav.

pornography does play a role in conveying a
message of support for aggressive behavior
towards women.
In the third (control) condition, the article discussed
sex relations in the golden years. After reading
the article, participants answered several questions
about the article to strengthen the cover story.
In addition, participants in the evolutionary and
social-constructivist conditions were also asked to
evaluate the scientific significance of the evidence
presented in the article that they had read.
Responses to this question were open-ended.
A quantitative coding and comparison of these
responses (see Results and Discussion, below)
allowed us to empirically ascertain whether the
evolutionary and social-constructivist explanations
for rape were perceived to be equally compelling.
Participants subsequently read a vignette that
described a man (‘‘Thomas’’) who, while on a date
with a woman who willingly kissed him, persisted in
forcing his sexual desire on her despite her explicit
protests and attempts to make him stop (i.e. a date
rape). Next, participants completed a questionnaire
assessing evaluations of sexually aggressive beha-
vior. Sample items include ‘‘How acceptable do you
find Thomas’s behavior to be?’’ and ‘‘How likely
is it for a man to behave as Thomas did in this
situation?’’
Participants also completed a five-item question-
naire assessing perceptions of a man’s control
over his sexual urges. Sample items include: ‘‘How
much conscious control did Thomas have over
his actions,’’ and ‘‘Rape is an expression of an
uncontrolled desire for sex.’’
Finally, participants were asked what would be
an appropriate prison term as punishment for
Thomas’s act. Responses were expressed in months
and/or years, with explicit bounds of 0 (no punish-
ment) and 20 years. Following the experiment,
participants were fully debriefed with regard to the
study hypotheses.
Results and Discussion. Three participants
reported some suspicion regarding the purpose
of the study. We report results that include all
participants. (Effect sizes and statistical significance
remain virtually unchanged if suspicious parti-
cipants are excluded from analyses.)
In a preliminary analysis, we assessed whether the
two scientific explanations for rape (evolutionary vs.
social-constructivist) were perceived to be equally
compelling. Participants’ open-ended evaluations of
the significance of the scientific evidence presented in
the article were coded using a simple coding scheme
that rated their response on a 3-point scale (15not
scientific at all, 2 5somewhat scientifically signi-
ficant, 3 5very scientific and significant). Two trained
coders rated the participants’ answers using this
scheme. The interrater reliability for the raters yielded
a Cohen’s Kappa of .84 Po.001 [95% CI (.74, .95)],
indicating a substantial level of agreement. Disagree-
ments were solved by deferring to the senior coder. An
analysis of variance (ANOVA) indicated no signifi-
cant differences among men in the different conditions
(all PsZ.3). These findings indicate that, to the extent
that evolutionary and the social-constructivist expla-
nations lead to different evaluations of offenders,
these differences cannot be attributed to any differ-
ence in the perceived scientific persuasiveness of the
particular explanations used here.
One set of primary analyses focused on judgments
of the extent to which men can control their sexual
urges. A composite control index was created as the
mean of the five items assessing perceived control
(Cronbach’s a5.64). This index was analyzed with
a single factor ANOVA. There was a significant
effect of the manipulation, F(2, 64) 57.16, Po.01,
Z25.18. As predicted, Fisher PLSD post hoc com-
parisons showed that men’s perceptions of control
were greatest in the social-constructivist condition
(M55.36, SD 51.08), relative to both the evolu-
tionary condition (M54.21, SD 51.06, Po.01) and
the control condition (M54.60, SD 50.89, Po.05).
The latter two conditions did not differ significantly
(P4.15).
A second set of analyses focused on general
evaluations of male sexual aggression. The four
evaluation items were highly correlated, loaded on a
single factor, and a composite index had acceptable
internal consistency (Cronbach’s a5.70). The mani-
pulation exerted a significant impact on evaluations
of male sexual aggressiveness, F(2, 64) 53.89, Po.05,
Z25.11. Supporting our hypothesis, Fisher PLSD
post hoc comparisons revealed that men evaluated
sexual aggressiveness most harshly in the social-
constructivist condition (M53.01, SD 50.72),
compared with both the evolutionary condition
(M53.80, SD 51.00, Po.01) and the control
condition (M53.60, SD 51.09, Po.05). The latter
two conditions did not differ significantly (P4.5).
A third set of analyses focused specifically on
punitive judgments (the recommended prison sen-
tence for Thomas). Because there was considerable
heterogeneity of variances (Levine test: F(2, 58) 5
14.71, Po.001), a cubic root transformation was
applied to reduce this heterogeneity prior to analysis
with a single factor ANOVA. There emerged a
manipulation effect, F(2, 58) 56.00, Po.01, Z25.17.
446 Dar-Nimrod et al.
Aggr. Behav.

Providing support for our hypothesis, Fisher
PLSD post hoc comparisons revealed that men were
significantly more punitive in the social-constructivist
condition (M51.31, SD 50.78, Po.01) relative
to both the evolutionary condition (M50.74,
SD 50.52, Po.05) and the control condition
(M50.67, SD 50.58, Po.01). These latter two
conditions did not differ significantly (P4.5). For
ease of interpretation, Figure 2 presents results on the
untransformed variable (mean recommended prison
term, in years; statistical analyses on the untrans-
formed variable revealed similar differences to those
reported above).
Additional analyses revealed that the effect of the
article manipulation on the composite evaluation
index was mediated by beliefs about male control
over sexual urges. We dummy-coded the manipula-
tion variable contrasting each of the experimental
conditions with the control condition. Similar to
the ANOVA results, only the contrast between the
social-constructivist condition and the control
condition significantly predicted evaluations of
male sexual aggression (b5".28, Po.05). When
perceived control was added as a predictor, this
contrast was no longer significant (b5".15,
t5"1.16, P4.10), whereas there was a significant
relation between perceived control and evaluation of
male sexual aggression, (b5".39, t53.17, Po.01).
Moreover, with perceived control as an added
predictor, variance explained increased from
R
2
5.108 to R
2
5.231, DF(1, 63) 510.03, Po.01.
A Sobel test corroborated our prediction that
perceived control mediated the effect of the Article
manipulation on men’s evaluation of male sexual
aggression, z51.96, Po.05, one tailed.
A parallel set of analyses assessed whether the
effect of the manipulation on punishment judgments
was also mediated by perceived control. The pattern
of results was similar to that from the evaluation
index, but was not significant (Sobel test z51.42,
Po.10, one tailed). When perceived control was
added as a predictor, variance explained increased
from R
2
5.171 to R
2
5.212, DF(1, 57) 52.96,
Po.05, one tailed. In this context, the relationship
between perceived control and punishment was
significant (b5.22, t51.72, Po.05, one tailed).
In summary, there was clear evidence that the
article manipulation influenced men’s perceptions
of male sexual aggressiveness. Compared with a
control condition, there was no effect of an
evolutionary explanation, but there was an effect
of a social-constructivist explanation. Exposure to a
social-constructivist explanation led men to judge
men to have greater control over their sexual urges,
and this in turn led to more negative evaluations of
male sexual aggressiveness. Exposure to a social-
constructivist explanation also led men to recom-
mend harsher punishments for a male sexual
aggressor. The finding that perceptions of control
over one’s sexual urges mediated the effect of the
manipulation on the evaluation of the behavior
suggests that control perception, rather than social
desirability concerns, generated the increased con-
demnation of the rape behavior in the social
constructivist condition as predicted by the genetic
essentialist biases framework [Dar-Nimrod and
Heine, 2011].
GENERAL DISCUSSION
Do scientific theories affect men’s evaluations of
sex crimes? Across two experiments, the effects were
clear and consistent. Consistent with our hypo-
theses, exposure to evolutionary theories had no
observable effect on the way that men think about
and evaluate sex crimes; but exposure to social-
constructivist theories did have an effect, leading
men to respond to sexual offenses more critically
and punitively. Additional data (from Study 2)
suggest that the latter effect may be mediated by
beliefs about men’s ability to control their own
sexual behavior.
Before considering the implications of these
results, it is important to bear in mind several
limitations as well. First, the methods assessed
responses immediately after exposure to articles
articulating scientific theories. It is possible that
these effects would not persist over time. Second, the
methods do not address the consequences of long-
term or repeated exposures to different kinds of
scientific theories, nor do they address the possibility
that responses in control conditions could them-
selves result from previous exposure to specific kinds
0
1
2
3
4
5
6
Evolutionary Sociocultural Control
Condi tion
Incarceration (in years)
Fig. 2. Punishment of a sexual aggressor in each of three experimental
conditions.
447Scientific Theories and Sex Crimes
Aggr. Behav.

of scientific theories (e.g. previous exposure to
evolutionary theories of male promiscuity). Third,
these methods exposed participants to very specific
examples of evolutionary and social-constructivist
theories. There are, of course, many different
theories within these two broad scholarly categories,
and it is possible that exposure to different exemplars
of these categories might produce a different pattern
of results. Finally, these experiments were conducted
on participants drawn from a particular population
(Canadian university students), and the results may
not be representative of results obtained from people
more generally [Henrich et al., 2010]. It will be
important to assess whether the effects generalize to
other contexts and other populations as well.
Bearing those limitations and caveats in mind,
there are nonetheless several interesting conclusions
that are implied by these results. Despite the findings
that men judged the evolutionary and social
constructivist explanations to be equally compelling,
only the social constructivist manipulations seem to
have affected their evaluations and judgments of
sexual misbehaviors. These findings suggest an
implicit nativism among men such that they may
habitually assume some biological basis for male illegal
sexual behaviors. This nativism might be temporarily
trumped by exposure to social-constructivist explana-
tions, which appear to imply greater individual
culpability [Monterosso et al., 2005]. In both experi-
ments, and in the majority of sex crimes, the men were
the aggressors and the women were the victims. Future
research may explore how women are affected by
exposure to scientific theories which explain women’s
sexual misbehaviors.
Although these results are generally consistent
with the idea that scientific theories have implica-
tions of moral and practical relevance, these results
are mostly inconsistent with the specific moral
criticisms directed against evolutionary psycho-
logical theories of sexual behavior. Contrary to the
‘‘get-out-of-jail-free-card’’ criticism summarized by
many critics of evolutionary psychology [e.g. Begley,
2009; Buller, 2005], there was no evidence that
priming evolutionary theories incline men to justify
or excuse male sexual misbehaviors (although it is
possible that previous exposure may have contri-
buted to shape their default theories). On the other
hand, incorporating information about the potential
evolutionary origin of sexual aggression into rape-
reduction interventions (as Thornhill and Palmer
[2000] suggested) does not seem to garner support
from this study either. Instead, men’s evaluations
of male sexual misbehavior were affected only by
social-constructivist theories.
It is likely, however, that social-constructivist
theories have this effect not because they are social-
constructivist per se, but because they focus attention
on causal variables (language use, social norms, etc.)
that laypeople recognize as malleable and non-
deterministic—and thus imply personal control and
culpability. But, in fact (despite misperceptions to the
contrary), malleability and nondeterminism are also a
hallmark of genetic and evolutionary perspectives on
social behavior [Carroll, 2005; Neuberg et al., 2010;
Ridley, 2003]. The differential consequences of
evolutionary and social-constructivist theories may
disappear if people are exposed to and educated
about evolutionary psychological theories that
explicitly emphasize the highly variable, context-
dependent, and decidedly nondeterministic relations
between genes and their behavioral consequences.
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