Recent advances in the cognitive neuroscience of action have considerably enlarged our understanding of human motor cognition. In particular, the activity of the mirror system, first discovered in the brain of non-human primates, provides an observer with the understanding of a perceived action by means of the motor simulation of the agent's observed movements. This discovery has raised the prospects of a motor theory of social cognition. Since human social cognition includes the ability to mindread, many motor theorists of social (...) cognition try to bridge the gap between motor cognition and mindreading by endorsing a simulation account of mindreading. Here, we express our skepticism about the motor theory of social cognition. (shrink)

A model is presented to account for the natural selection of what is termed reciprocally altruistic behavior. The model shows how selection can operate -against the cheater (non-reciprocator) in the system. Three instances of altruistic behavior are discussed, the evolution of which the model can explain: (1) behavior involved in cleaning symbioses; (2) warning cries in birds: and (3) human reciprocal altruism. Regarding human reciprocal altruism, it is shown that the details of the psychological system that regulates this altruism can (...) be explained by the model. Specifically, friendship,d islike, moralistic aggression, gratitude, sympathy, trust, suspicion, trustworthiness, aspects of guilt, and some forms of dishonesty and hypocrisy can be explained as important adaptations to regulate the altruistic system. Each individual human is seen as possessing altruistic and cheating tendencies, the expression of which is sensitive to developmental variables that were selected to set the tendencies at a balance appropriate to the local social and ecological environment. (shrink)

The transfer of food among group members is a ubiquitous feature of small-scale forager and forager-agricultural populations. The uniqueness of pervasive sharing among humans, especially among unrelated individuals, has led researchers to evaluate numerous hypotheses about the adaptive functions and patterns of sharing in different ecologies. This article attempts to organize available cross-cultural evidence pertaining to several contentious evolutionary models: kin selection, reciprocal altruism, tolerated scrounging, and costly signaling. Debates about the relevance of these models focus primarily on the extent (...) to which individuals exert control over the distribution of foods they acquire, and the extent to which donors receive food or other fitness-enhancing benefits in return for shares given away. Each model can explain some of the variance in sharing patterns within groups, and so generalizations that ignore or deny the importance of any one model may be misleading. Careful multivariate analyses and cross-cultural comparisons of food transfer patterns are therefore necessary tools for assessing aspects of the sexual division of labor, human life history evolution, and the evolution of the family. This article also introduces a framework for better understanding variation in sharing behavior across small-scale traditional societies. I discuss the importance of resource ecology and the degree of coordination in acquisition activities as a key feature that influences sharing behavior. (shrink)

When people describe motion events, their path expressions are biased toward inclusion of goal paths (e.g., into the house) and omission of source paths (e.g., out of the house). In this paper, we explored whether this asymmetry has its origins in people’s non-linguistic representations of events. In three experiments, 4-year-old children and adults described or remembered manner of motion events that represented animate/intentional and physical events. The results suggest that the linguistic asymmetry between goals and sources is not fully rooted (...) in non-linguistic event representations: linguistic descriptions showed the goal bias for both kinds of events, whereas non-linguistic memory for events showed the goal bias only for events involving animate, goal-directed motion. The findings are discussed in terms of the mapping between non-linguistic representations of goals and sources in language, focusing on the role that linguistic principles play in producing a more absolute goal bias from more gradient non-linguistic representations of paths. (shrink)

We investigate a possible universal constraint on spatial meaning. It has been proposed that people attend preferentially to the endpoints of spatial motion events, and that languages may therefore make finer semantic distinctions at event endpoints than at event beginnings. We test this proposal. In Experiment 1, we show that people discriminate the endpoints of spatial motion events more readily than they do event beginnings—suggesting a non-linguistic attentional bias toward endpoints. In Experiment 2, speakers of Arabic, Chinese, and English each (...) described a set of spatial events displayed in video clips. Although the spatial systems of these languages differ, speakers of all three languages made finer semantic distinctions at event endpoints, compared to event beginnings. These findings are consistent with the proposal that event endpoints are privileged over event beginnings, in both language and perception. (shrink)

Recent research has demonstrated an asymmetry between the origins and endpoints of motion events, with preferential attention given to endpoints rather than beginnings of motion in both language and memory. Two experiments explore this asymmetry further and test its implications for language production and comprehension. Experiment 1 shows that both adults and 4-year-old children detect fewer within-category changes in source than goal objects when tested for memory of motion events; furthermore, these groups produce fewer references to source than goal objects (...) when describing the same motion events. Experiment 2 asks whether the specificity of encoding source/goal relations differs in both spatial memory and the comprehension of novel spatial vocabulary. Results show that endpoint configuration changes are detected more accurately than source configuration changes by both adults and young children. Furthermore, when interpreting novel motion verbs, both age groups expect more fine-grained lexical distinctions in the domain of endpoint configurations compared to that of source configurations. These studies demonstrate that a cognitive-attentional bias in spatial representation and memory affects both the detail of linguistic encoding during the use of spatial language and the specificity of hypotheses about spatial referents that learners build during the acquisition of the spatial lexicon. (shrink)

The study of reciprocal altruism, or the exchange of goods and services between individuals, requires attention to both evolutionary explanations and proximate mechanisms. Evolutionary explanations have been debated at length, but far less is known about the proximate mechanisms of reciprocity. Our own research has focused on the immediate causes and contingencies underlying services such as food sharing, grooming, and cooperation in brown capuchin monkeys and chimpanzees. Employing both observational and experimental techniques, we have come to distinguish three types of (...) reciprocity. Symmetry-based reciprocity is cognitively the least complex form, based on symmetries inherent in dyadic relationships (e.g., mutual association, kinship). Attitudinal reciprocity, which is more cognitively complex, is based on the mirroring of social attitudes between partners and is exhibited by both capuchin monkeys and chimpanzees. Finally, calculated reciprocity, the most cognitively advanced form, is based on mental scorekeeping and is found only in humans and possibly chimpanzees. (shrink)

Human cooperation is a key driving force behind the evolutionary success of our hominin lineage. At the proximate level, biologists and social scientists have identified other-regarding preferences – such as fairness based on egalitarian motives, and altruism – as likely candidates for fostering large-scale cooperation. A critical question concerns the ontogenetic origins of these constituents of cooperative behavior, as well as whether they emerge independently or in an interrelated fashion. The answer to this question will shed light on the interdisciplinary (...) debate regarding the significance of such preferences for explaining how humans become such cooperative beings. We investigated 15-month-old infants' sensitivity to fairness, and their altruistic behavior, assessed via infants' reactions to a third-party resource distribution task, and via a sharing task. Our results challenge current models of the development of fairness and altruism in two ways. First, in contrast to past work suggesting that fairness and altruism may not emerge until early to mid-childhood, 15-month-old infants are sensitive to fairness and can engage in altruistic sharing. Second, infants' degree of sensitivity to fairness as a third-party observer was related to whether they shared toys altruistically or selfishly, indicating that moral evaluations and prosocial behavior are heavily interconnected from early in development. Our results present the first evidence that the roots of a basic sense of fairness and altruism can be found in infancy, and that these other-regarding preferences develop in a parallel and interwoven fashion. These findings support arguments for an evolutionary basis – most likely in dialectical manner including both biological and cultural mechanisms – of human egalitarianism given the rapidly developing nature of other-regarding preferences and their role in the evolution of human-specific forms of cooperation. Future work of this kind will help determine to what extent uniquely human sociality and morality depend on other-regarding preferences emerging early in life. (shrink)