Social exchange and evolutionary models of mate selection incorporate economic assumptions but have not considered a key distinction between necessities and luxuries. This distinction can clarify an apparent paradox: Status and attractiveness, though emphasized by many researchers, are not typically rated highly by research participants. Three studies supported the hypothesis that women and men first ensure sufficient levels of necessities in potential mates before considering many other characteristics rated as more important in prior surveys. In Studies 1 and 2, participants designed ideal long-term mates, purchasing various characteristics with 3 different budgets. Study 3 used a mate-screening paradigm and showed that people inquire 1st about hypothesized necessities. Physical attractiveness was a necessity to men, status and resources were necessities to women, and kindness and intelligence were necessities to both.

Conspicuous displays of consumption and benevolence might serve as "costly signals" of desirable mate qualities. If so, they should vary strategically with manipulations of mating-related motives. The authors examined this possibility in 4 experiments. Inducing mating goals in men increased their willingness to spend on conspicuous luxuries but not on basic necessities. In women, mating goals boosted public-but not private-helping. Although mating motivation did not generally inspire helping in men, it did induce more helpfulness in contexts in which they could display heroism or dominance. Conversely, although mating motivation did not lead women to conspicuously consume, it did lead women to spend more publicly on helpful causes. Overall, romantic motives seem to produce highly strategic and sex-specific self-presentations best understood within a costly signaling framework.

The finding that women are attracted to men older than themselves whereas men are attracted to relatively younger women has been explained by social psychologists in terms of economic exchange rooted in traditional sex-role norms. An alternative evolutionary model suggests that males and females follow different reproductive strategies, and predicts a more complex relationship between gender and age preferences. In particular, males' preferences for relatively younger females should be minimal during early mating years, but should become more pronounced as the male gets older. Young females are expected to prefer somewhat older males during their early years and to change less as they age. We briefly review relevant theory and present results of six studies testing this prediction. Study 1 finds support for this gender-differentiated prediction in age preferences expressed in personal advertisements. Study 2 supports the prediction with marriage statistics from two U.S. cities. Study 3 examines the cross-generational robustness of the phenomenon, and finds the same pattern in marriage statistics from 1923. Study 4 replicates Study 1 using matrimonial advertisements from two European countries, and from India. Study 5 finds a consistent pattern in marriages recorded from 1913 through 1939 on a small island in the Philippines. Study 6 reveals the same pattern in singles advertisements placed by financially successful American women and men. We consider the limitations of previous normative and evolutionary explanations of age preferences and discuss the advantages of expanding previous models to include the life history perspective.

Are there sex differences in criteria for sexual relationships? The answer depends on what question a researcher asks. Data suggest that, whereas the sexes differ in whether they will enter short-term sexual relationships, they are more similar in what they prioritize in partners for such relationships. However, additional data and context of other findings and theory suggest different underlying reasons. In Studies 1 and 2, men and women were given varying "mate budgets" to design short-term mates and were asked whether they would actually mate with constructed partners. Study 3 used a mate-screening paradigm. Whereas women have been found to prioritize status in long-term mates, they instead (like men) prioritize physical attractiveness much like an economic necessity in short-term mates. Both sexes also show evidence of favoring well-rounded long- and short-term mates when given the chance. In Studies 4 and 5, participants report reasons for having casual sex and what they find physically attractive. For women, results generally support a good genes account of short-term mating, as per strategic pluralism theory (S. W. Gangestad & J. A. Simpson, 2000). Discussion addresses broader theoretical implications for mate preference, and the link between method and theory in examining social decision processes.

For the past two decades the person-situation debate has dominated personality psychology and had important repercussions in clinical, social, and organizational psychology. This controversy strikes to the heart of each of these disciplines because it puts on trial the central assumption that internal dispositions have an important influence on behavior. According to emerging views of scientific progress, controversy serves the useful function of narrowing the field of competing hypotheses. In this light, we examine seven hypotheses that arose during the course of the person-situation debate, ranging from most to least pessimistic about the existence of consensual, discriminative personality traits. The accumulated evidence fails to support the hypotheses that personality traits are simply (a) in the eye of the beholder, (b) semantic illusions, (c) artifacts of base-rate accuracy, (d) artifacts of shared stereotypes, (e) due to discussion between observers (who ignore behavior in favor of verbal self-presentation or reputation), or (f) mere by-products of situational consistencies. Evidence also fails to support the hypothesis (g) that although traits are related to behavior, the relationship is too small to be important. Yet we have not simply come full circle to a reacceptance of traits as they were understood 20 years ago. Research generated by these hypotheses has allowed us to better specify the circumstances under which personality assessments will be valid.Whether we are acting as professional psychologists, as academic psychologists, or simply as lay psychologists engaging in everyday gossip, the assumption that people have "traits" (or enduring cross-situational consistencies in their behavior) provides a basis for many of our decisions. When a clinical or counseling psychologist uses a standard assessment battery, he or she assumes that there is some degree of trait-like consistency in pathological behavior to be measured. When an organizational psychologist designs a personnel selection procedure, he or she assumes that consistent individual differences between the applicants are there to be found. When an academic psychologist teaches a course in personality, he or she must either assume some consistency in behavior or else face a bit of existential absurdity for at least three hours a week. Likewise, a good portion of our courses on clinical and developmental psychology would be unimaginable unless we assumed some cross-situational consistency.Even in everyday lay psychology, our attempts to analyze the behaviors of our friends, relatives, and co-workers are riddled with assumptions about personality traits.Despite the wide appeal of the trait assumption, personality psychologists have been entangled for some time in a debate about whether it might be based more on illusion than reality (e.g., Alker

Findings of 7 studies suggested that decisions about the sex of a face and the emotional expressions of anger or happiness are not independent: Participants were faster and more accurate at detecting angry expressions on male faces and at detecting happy expressions on female faces. These findings were robust across different stimulus sets and judgment tasks and indicated bottom-up perceptual processes rather than just top-down conceptually driven ones. Results from additional studies in which neutrally expressive faces were used suggested that the connections between masculine features and angry expressions and between feminine features and happy expressions might be a property of the sexual dimorphism of the face itself and not merely a result of gender stereotypes biasing the perception.

Individual differences are explicitly connected to social interaction in Darwin's notion of sexual selection. Traits that increase the probability of successful reproduction will tend to increase in frequency. This process operates partly through differential choice, by one sex, of certain traits in the other. According to the parental investment model, females frequently have more stringent criteria for the traits they will accept in a mate because they have a relatively larger investment in each offspring. Because human mating arrangements often involve a substantial commitment of resources by the male, it is necessary to invoke a distinction between the selectivity involved during casual mating opportunities and the selectivity exercised when choosing a long-term partner. Ninety-three undergraduate men and women rated their minimum criteria on 24 partner characteristics at four levels of commitment. In line with an unqualified parental investment model, females were more selective overall, particularly on status-linked variables. In line with a qualified parental investment model, males' trait preferences depended upon the anticipated investment in the relationship. Males had lower requirements for a sexual partner than did females, but were nearly as selective as females when considering requirements for a long-term partner.

Humans likely evolved precautionary systems designed to minimize the threats to reproductive fitness posed by highly interdependent ultrasociality. A review of research on the self-protection and disease avoidance systems reveals that each system is functionally distinct and domainspecific: Each is attuned to different cues; engages different emotions, inferences, and behavioral inclinations; and is rooted in somewhat different neurobiological substrates. These systems share important features, however. Each system is functionally coherent, in that perceptual, affective, cognitive, and behavioral processes work in concert to reduce fitness costs of potential threats. Each system is biased in a risk-averse manner, erring toward precautionary responses even when available cues only heuristically imply threat. And each system is functionally flexible, being highly sensitive to specific ecological and dispositional cues that signal greater vulnerability to the relevant threat. These features characterize a general template useful for understanding not only the self-protection and disease avoidance systems, but also a broader set of evolved, domainspecific precautionary systems. Key Words/PhrasesSelf-Protection; Disease Avoidance; Threat Management; Precautionary Psychology; Evolutionary Psychology; Domain Specificity; Fear; Disgust; Prejudice; Stigma; Social Cognition; Motivation; Error ManagementIn the second half of the 20 th century, cognitive scientists made great progress by thinking of the brain in computational terms. Although the brain is indeed an information-processing device, it is not a mere computer. Rather than being designed by engineers to process information in a dispassionate manner, the human brain has been designed by natural selection to be something of a motivational device to promote adaptive behavioral responses to critical challenges directly related to survival and reproductive fitness. The result is not only a great number of cognitive and behavioral mechanisms for efficiently and effectively