The visual environment of Cree Indians from the east coast of James Bay, Quebec, is different from that of city-raised Euro-Canadians. So also are their corresponding orientation anisotropies in visual acuity. A Euro-Canadian sample exhibited the usual higher resolution for vertically and horizontally oriented gratings as compared with oblique orientations, while a Cree Indian sample did not. The most parsimonious explanation of these acuity differences is that orientation-specific detectors in humans are tuned by the early visual environment.

Examined is the hypothesis that the psychological response to social change would vary as a function of both the acculturative pressures brought to bear on a community, and the traditional cultural and behavioural features that characterize the community. By sampling from communities of Amerindian peoples, across an eco-cultural range, evidence was presented which indicated that the greater the cultural discontinuities across cultures, then the greater the acculturative stress; within Amerindian communities, levels of psychological differentiation were negatively related to acculturative stress. Specific cultural and individual differences must be taken into account when attempting to understand relationships between culture contact and acculturative stress; its course is not universal.

An affect discrepancy model is proposed to explain the processes by which children come to know and identify with a minority or majority group. According to this model, which integrates ideas from cognitive-development and social identity theories, level of cognitive structure and self-esteem predict own-group attitudes. In both minority and majority group children, increases in cognitive structure is associated with the development of positive own-group attitudes. Self-esteem is also associated with own-group attitudes but the relationship differs for minority and majority children. Among majority children self-esteem is positively related to own-group attitudes, but is inversely related for minority children. To test this model, White and Indian children in kindergarten and grades one and two answered racial identity, preference, social distance and recognition questions by pointing to pictures of Whites, Indians and Blacks. Several weeks later subjects completed measures of concrete operational thought and self-esteem. Indian children made more cross-racial choices than did Whites, even though Indians were more accurate than Whites in recognizing the pictures. Structural equation models indicated that for both groups, cognitive development was positively associated with own-group choices. Self-esteem was positively related to own-group choices for Whites but inversely related for Indians. Results were discussed in terms of the affect-discrepancy model, particularly in regards to the influence of level of cognitive structure and self-esteem on own-group identity. ResumeNous proposons un modele de divergence affective pour expliquer les processus par lesquels les enfants viennent a s'identifier a un groupe minoritaire oil majoritaire. Selon ce modele, qui integre des idees puisees dans les theories du deVeloppement cognitif ct de l'identite sociale, le niveau de developpement de la structure cognitive et Ie degre d'estime de soi permettent de predire les attitudes a l'egard du groupe d'appartenance. Chez les deux groupes d'enfants (majoritaire ct minoritaire), l'accroissement de la complexity cognitive est relie'e au deVeloppement d'attitudes positives envers le groupe d'appartenance. L'estime de soi est egalement reliee a ces attitudes, mais la relation differe pour les enfants appartenant a un groupe minoritaire et pour les enfants du

A model which examined interrelationships among ecological setting, cultural adaptation and psychological differentiation was proposed. Details of each element of the model were discussed, and behavioural predictions were made. Specifically, hunters and gatherers, who were migratory and low in population density and food accumulation were expected to exhibit high levels of psychological differentiation in perceptual, social and affective areas of psychological differentiation. Conversely, sedentary peoples who were higher in population density and food accumulation were expected to exhibit lower levels of differentiation, while those peoples who were ecologically intermediate were expected to exhibit moderate levels. Sampling in Amerindian communities, and comparing these new data to previous African, Australian, and Eskimo data, led to the conclusion that higher levels of differentiation in perceptual, social and affective domains do indeed characterize hunters and gatherers. However, such differences within a single culture area were minimal. An examination of the cross‐cultural stability of the concept of psychological differentiation suggested greatest internal consistency for hunters and gatherers, and less for sedentary peoples; constant relationships with socialization emphases were found, while variations in sex differences were related to features of socio‐cultural stratification.