Lisa DeBruine (website), University of St. Andrews Facial resemblance and kin recognition: Context-specific effects of 'mere' exposure Studies using computer graphics to manipulate facial resemblance to participants have demonstrated behaviors and preferences consistent with the use of facial resemblance as a cue of kinship. Consistent with predictions from inclusive fitness theory, people favour individuals represented by resembling faces in an economic game. Kinship cues are sensitive to contexts in which the adaptive response should be different. Although self-resemblance increases the perceived "averageness" of both male and female faces, self-resemblance increases the attractiveness of same-sex faces only. Additionally, self-resemblance of other-sex faces increases attributions of trustworthiness, has no effect on attractiveness for a long-term relationship, and decreases attractiveness for a short-term relationship. Although responses to facial resemblance undoubtedly require visual experience with one's own or family members' faces, non-adaptive hypotheses explaining these results as simple byproducts of general perceptual mechanisms (e.g. the mere exposure effect) are not supported. Responses to facial resemblance seem best interpreted as evidence of specialized adaptations to the problems of kin recognition in the domains of mate choice and prosocial behaviour. Helen Fisher (website), Rutgers University & J. Anderson Thomson, University of Virginia The brain in love: An fMRI study of romantic love and how serotonin-enhancing antidepressants can jeopardize courtship, romance and marriage This paper proposes that romantic love is a developed form of mammalian mating drive designed to motivate men and women to focus courtship energy on preferred reproductive partners. Fisher and colleagues Arthur Aron, Lucy Brown and others put 17 men and women who had "just fallen madly in love" into a functional Magnetic Resonance Imaging (fMRI) machine to identify the brain circuitry of romantic love. Participants alternately viewed a photo of a beloved and a photo of a familiar, emotionally neutral individual, interspersed with a distraction task. Dopamine pathways associated with reward and motivation were activated; regions of activation changed as the relationship endured; and men and women exhibited some different brain responses. Fisher proposes that romantic love is largely distinct from the sex drive; that it evolved to facilitate mate choice; that gender differences in romantic passion reflect varied ancestral male and female reproductive strategies; that this brain system is integrated with brain networks for hate/rage; that romantic love can become a life-threatening addiction; that waning romantic attraction across time is an adaptation for child rearing; and that the use of serotonin-enhancing antidepressants can adversely affect several evolved brain mechanisms for reproduction, including mate assessment, mate preference, romantic attraction and long term attachment. This paper discusses the traits, biology and functions of romantic love, and explores the biological inter-relationships between romantic love and the other two primary brain systems for reproduction, lust and attachment, to illustrate how serotonin-enhancing antidepressants can jeopardize courtship, romance, marriage and fertility. Jonathan Haidt (website), University of Virginia Intuitive ethics: How a small set of evolved intuitions gives rise to culturally variable virtues Morality has long been thought to come from outside, from God, society, or parents into children, who are empty vessels. In contrast, an "externalization" model is presented in which four cognitive/affective modules generate intuitions about social events. The modules respond to issues of harm/suffering, reciprocity/fairness, hierarchy/duty, and purity/piety. (This theory draws heavily on the work of A. Fiske and R. Shweder.) The modules were created by natural selection, but they can only be understood as having co-evolved with cultural learning. Cultures create variable sets of virtues that are grounded in and constrained by the four modules. The case of the purity module is worked out in detail, including experimental demonstrations that flashes of irrelevant disgust (triggered by hypnosis, or by working at a dirty desk) make moral judgments more severe. Lee Kirkpatrick (website), College of William and Mary But is it really attachment? Some evolutionary perspectives on romantic love Attachment theory has emerged over the last decade or so as a dominant approach to the study of romantic relationships within social and personality psychology. However, although Bowlby's theory of infant-caregiver relationships was grounded firmly in an evolutionary model of adaptive design and function, extensions of the theory to adult love relationships have generally proceeded apace in the absence of an evolutionary framework. In this paper I critically examine the notion, from an evolutionary-psychological perspective, that romantic love involves the same psychological mechanisms and processes that underlie infant-mother attachments. In contrast to (the few) previous attempts to specify the evolutionary logic of romantic love-as-attachment, this analysis (1) begins from a general perspective on human mating strategies as pluralistic and facultative; (2) draws a crucial distinction between Bowlby's two meanings of attachment as a behavior-control system (with the adaptive function, in infants, of protection) and attachment as a socioemotional bond related to “love”; and (3) considers the adaptive function(s) of romantic love in relation to other evolutionary perspectives, including Robert Frank's model of emotions as commitment devices and Tooby and Cosmides' model of altruism in deep-engagement relationships. With respect to measured individual differences in adult attachment, I offer new data to support the hypothesis that existing measures may largely be tapping variability in sociosexuality -- specifically, orientation toward a long-term/restricted mating strategy -- rather than attachment dynamics as such. I conclude that the role of attachment per se in adult romantic relationships may be far more limited than adult-attachment researchers have heretofore assumed. Rob Kurzban (website), & Sheen S. Levine, University of Pennsylvania The adaptive design of friendship systems: Sensitivity to cues of social network structure Debate continues regarding the cognitive mechanisms that underpin the behavior and affect surrounding the phenomenon of friendship. We propose that one feature of this evolved psychology is a cognitive system that computes “cascading benefits,” the extent to which delivering benefits to one's social ties simultaneously delivers benefits to those who have an interest in the target individual's well being. If this is the case, manipulating the extent to which one perceives a given friend or acquaintance as having mutual social ties should influence one's perception of the relationship with that friend or acquaintance. To test this, we ran an experiment in which participants nominated two close friends and two acquaintances, and rated these four individuals on a number of scales. Participants completed a distracter task, and subsequently were asked to think of either ten people that they and the friend or acquaintance share in common or ten people who the participant knew but the friend or acquaintance did not. Participants evaluated the four individuals on the same scales as in the first part of the experiment. Consistent with predictions, we found that thinking of people who a close friend did not know decreased feelings of closeness and liking for that friend, while thinking of people known by the participant and an acquaintance led to increased feelings of closeness to and liking for that acquaintance. Steve Neuberg (website), Arizona State University Discriminating sociality: A sociofunctional approach to intragroup and intergroup relations What characteristics and behaviors do we most value in others, and how do we treat those who don't possess or exhibit them? The standard social science model presumes that human social preferences are culturally determined, arbitrary, and thus highly variable across social contexts. While not denying a critical role for sociocultural processes, we suggest that human social preferences are significantly (but imperfectly) constrained by our evolved nature as ultrasocial animals. In light of the extensiveness of human social interdependence and group investment, we believe that people value individuals and groups seen as facilitating effective ingroup functioning and stigmatize those seen as threatening it. Based on a consideration of group processes and structures fundamental to group success, I derive preliminary taxonomies of (1) specific social threats to which people are generally attuned, and (2) specific emotional and behavioral responses these threats elicit. I then illustrate several implications of this "sociofunctional" framework with data from two ongoing investigations: The first explores the particular personality traits people value and devalue for different types of affiliations. The second explores the connections between the threats people believe certain individuals and groups pose and the specific emotional reactions these others elicit; this line of research also explores the hypothesis that the traditional conception of prejudice-as-a-general-attitude masks the highly textured nature of intergroup affect. Finally, I note the integrative potential of the proposed framework and its implications for better understanding social phenomena ranging from self-presentation to formal religious and legal practices. Valerie Stone (website), University of Queensland Domain-specific and domain-general adaptations in hominid evolution: Theory of mind, recursion and executive function Abstract TBA Margo Wilson (website) & Martin Daly (website), McMaster University When is the future worth less than the present? People generally place more value on the here and now than on the distant future, but to what extent? Future discounting varies between the sexes and in relation to age, as well as in response to cues of the probability of surviving to reap future benefits. Men discount the future more steeply than women, both because men are less likely to live to see the future, and because immediate, even total, resource expenditure was more likely to contribute to genetic posterity for our male ancestors than for our female ancestors. We will illustrate these variations in discounting with data on violent risk-taking, and an experimental laboratory study.