Advocates of Darwinian approaches to the study of behavior are divided over what an evolutionary perspective is thought to entail. Some take "evolution-mindedness" to mean "phylogeny-mindedness," whereas others take it to mean "adaptationmindedness." Historically, comparative psychology began as the search for mental continuities between humans and other animals: a phylogenetic approach. Independently, ethologists and now behavioral ecologists have placed far more emphasis on the nichedifferentiated mental abilities unique to the species being investigated: an adaptive approach. We argue that the output of complex, dynamical systems can be dramatically changed by only minor changes in internal structure. Because selection acts on the consequences of behavior, the behavioral output of the psyche will be easily shaped by adaptive demands over evolutionary time, even though the modification of the neurophysiological substrate necessary to create such adaptive changes may be minor. Thus, adaptation-mindedness will be most illuminating in the study of cognition and behavior, whereas phylogeny-mindedness will be most illuminating in the study of their neurophysiological substrates. Similarly, a phylogenetic approach to cognition and behavior is likely to cause one to overlook our most interesting, complexly designed species-typical traits, whereas using animal psychology to exfoliate general principles of behavioral ecology represents our best hope of understanding humanity's many zoologically unique characteristics.

Relative social status strongly regulates human behavior, yet this factor has been largely ignored in research on risky decision making. Humans, like other animals, incur risks as they compete to defend or improve their standing in a social group. Among men, access to culturally important resources is a locus of intrasexual competition and a determinant of status. Thus, relative status should affect men's motivations for risk in relevant domains. Contrasting predictions about such effects were derived from dominance theory and risk-sensitive foraging theory. Experiments varied whether subjects thought they were being observed and evaluated by others of lower, equal or higher status, and whether decisions involved resources (status relevant) or medical treatments (status irrelevant). Across two experiments, men who thought others of equal status were viewing and evaluating their decisions were more likely to favor a high-risk/high-gain means of recouping a monetary loss over a no-risk/low-gain means with equal expected value. Supporting predictions from dominance theory, this motivation for risk taking appeared only in the equal status condition, only for men, and only for resource loss problems. Taken together, the results support the idea that motivational systems designed to negotiate a status-saturated social world regulate the cognitive processes that generate risky decision making in men. (c) 2008 Elsevier Inc. All rights reserved.

Baron-Cohen (1995) proposed that the theory of mind (ToM) inference system evolved to promote strategic social interaction. Social exchange-a form of co-operation for mutual benefit -involves strategic social interaction and requires ToM inferences about the contents of other individuals' mental states, especially their desires, goals, and intentions. There are behavioral and neuropsychological dissociations between reasoning about social exchange and reasoning about equivalent problems tapping other, more general, content domains. It has therefore been proposed that social exchange behavior is regulated by social contract algorithms: a domain-specific inference system that is functionally specialized for reasoning about social exchange. We report an fMRI study using the Wason selection task that provides further support for this hypothesis. Precautionary rules share so many properties with social exchange rules-they are conditional, deontic, and involve subjective utilities-that most reasoning theories claim they are processed by the same neurocomputational machinery. Nevertheless, neuroimaging shows that reasoning about social exchange activates brain areas not activated by reasoning about precautionary rules, and vice versa. As predicted, neural correlates of ToM (anterior and posterior temporal cortex) were activated when subjects interpreted social exchange rules, but not precautionary rules (where ToM inferences are unnecessary). We argue that the interaction between ToM and social contract algorithms can be reciprocal: social contract algorithms requires ToM inferences, but their functional logic also allows ToM inferences to be made. By considering interactions between ToM in the narrower sense (belief desire reasoning) and all the social inference systems that create the logic of human social interaction-ones that enable as well as use inferences about the content of mental states-a broader conception of ToM may emerge: a computational model embodying a Theory of Human Nature (ToHN).