Kevin MacDonald

Effortful control, explicit processing, and the regulation of human evolved predispositions.

This article analyzes the effortful control of automatic processing related to social and emotional behavior, including control over evolved modules designed to solve problems of survival and reproduction that were recurrent over evolutionary time. The inputs to effortful control mechanisms include a wide range of nonrecurrent information--information resulting not from evolutionary regularities but from explicit appraisals of costs and benefits. Effortful control mechanisms are associated with the ventromedial prefrontal cortex and the ventral anterior cingulated cortex. These mechanisms are largely separate from mechanisms of cognitive control (termed executive function) and working memory, and they enable effortful control of behavior in the service of long range goals. Individual differences in effortful control are associated with measures of conscientiousness in the Five Factor Model of personality. Research in the areas of aggression, ethnocentrism, sexuality, reward seeking, and emotion regulation is reviewed indicating effortful control of automatic, implicit processing based on explicit appraisals of the context. Evidence is reviewed indicating that evolutionary pressure for cooperation may be a critical adaptive function accounting for the evolution of explicit processing.

A perspective on Darwinian psychology: The importance of domain-general mechanisms, plasticity, and individual differences

Abstract In this paper a theory of Darwinian psychological adaptations as motive dispositions with an affective core is developed, and it is argued that 1) there is significant plasticity in these mechanisms; 2) in addition to domain-specific evolved motive dispositions, there are a variety of domain-general cognitive and emotional mechanisms; 3) humans are capable of developing motive dispositions which are not adaptations; 4) the relationship between evolved motive dispositions and behavior is very tenuous so that the explanatory power of Darwinian psychology is very weak; 5) individual differences in human psychological characteristics are evolutionarily meaningful and are linked to mechanisms which assess the resource value of intraspecific genetic and phenotypic diversity.

Evolution, Culture, and the Five-Factor Model:

Following areview of evolutionary approaches to the five-factor model (FEM), I develop a synthetic perspective that incorporates three levels of analysis: personality systems as universal psychological mechanisms, systematic group (i.e., gender, birth order, age, ethnic) differences that can be illuminated by evolutionary theory, and individual differences. At the level of universal mechanisms, personality systems are species-typical systems with adaptive functions in the human environment of evolutionary adaptedness. At the level of group differences, the evolutionary theory of sex, parent-offspring conflict theory, and life history are used to analyze sex, age, and ethnic differences in personality systems. At the level of individual differences, variation in personality consists of a range of viable evolutionary strategies for humans. Humans evaluate and act on the genetic and phenotypic diversity represented by this range of viable strategies to solve adaptive problems. Evolutionary perspectives on cross-cultural variation are noted and illustrated.

Parent-Child Physical Play with Rejected, Neglected, and Popular Boys.

This study compares the parent-child interactions of rejected, neglected, and popular boys in a paradigm emphasizing physical play. Twelve boys, 3 to 5 years of age, of each sociomctric category were recruited from nursery schools and observed in interactions with their parents at home, It was found that the fathers of neglected boys engaged in less affectively arousing, physical play than the fathers of popular and rejected boys. In addition, there was more overstimulation and avoidance of stimulation among the rejected boys compared with the popular boys. The results indicate the importance of the regulation of affect for social competence and illustrate strong links between the parent and peer social systems.

Mechanisms of sexual egalitarianism in Western Europe

Abstract This paper presents historical evidence on marriage patterns in ancient Sparta, Rome, Early Christianity, and the Early Middle Ages. Monogamy occurred in all of these societies but there is a great deal of diversity in origin and function of monogamous mating arrangements. In the case of Sparta, monogamy arose as part of an intensively egalitarian, racially homogenous social structure which fostered intense cooperation and altruism within the group. In the case of Rome monogamy coexisted with pronounced social, political, and economic inequalities, and there was much more ethnic diversity at Rome than at Sparta. The case of early Christianity involved the spread of a more radical ideology of monogamy and sexual restraint among the lower and middle classes of the Roman Empire, but the crucial event in the Christianization of the West was the apparently chance conversion of a single powerful individual, the Emperor Constantine. In the case of the Christianization of barbarian Europe, the movement was spearheaded by a powerful institution and the acceptance among the aristocracy of Christian ideology. The revolution thus proceeded from the top of the society downward. These findings are related to a model of cultural evolution that emphasizes the irreducibility of social controls and ideology in maintaining egalitarian mating practices.

Life history theory and human reproductive behavior: environmental / contextual influences and heritable variation.

The purpose of this article is to develop a model of life history theory that incorporates environmental influences, contextual influences, and heritable variation. I argue that physically or psychologically stressful environments delay maturation and the onset of reproductive competence. The social context is also important, and here I concentrate on the opportunity for upward social mobility as a contextual influence that results in delaying reproduction and lowering fertility in the interest of increasing investment in children. I also review evidence that variation in life history strategies is influenced by genetic variation as well. Finally, I show that cultural shifts in the social control of sexual behavior have had differential effects on individuals predisposed to high- versus low-investment reproductive strategies.

Civilization and its discontents revisited: Freud as an evolutionary biologist

Recent scholarly work has emphasized the importance of evolutionary theory as an element of Freuds thought. This paper compares the evolutionary logic of Civilization and Its Discontents with modern evolutionary logic, as represented by human sociobiology. Some of Freuds arguments are quite modern, but although they were consistent with the evolutionary theory of his time, his arguments in many cases depart radically from a modern viewpoint: Moreover, a modern viewpoint would lead to the rejection of several of the psychic mechanisms proposed by Freud to explain human behavior. Nevertheless, the ultimate evolutionary questions that Freud posed are of continuing interest and must be answered by any theory of behavior. Moreover, some of the theory used by modern sociobiologists to explain human behavior is formally similar to the arguments used by Freud.

RESOURCE APPRAISALS AMONG SELF, FRIEND AND LEADER: IMPLICATIONS FOR AN EVOLUTIONARY PERSPECTIVE ON INDIVIDUAL DIFFERENCES

Abstract The study was designed to illustrate an evolutionary approach to individual differences and friendship choice. Individual differences in personality and other trait dimensions are conceptualized as resource environments for individuals. Individuals are expected to evaluate this variation differently depending on a variety of variables and the present study evaluated the following: 1. (1) the putative role of the person being evaluated as ideal friend or ideal leader; 2. (2) subjects status as males or females; 3. (3) similarity to self. 372 subjects (279 females) completed the EAS Adult Temperament Survey and the Resource Appraisal Survey (RAS) for themselves, an ideal friend and an ideal leader. The combined EAS and RAS were factor analysed for males and females separately for 11 a priori factors (5 EAS, 6 RAS) using Principal Component Analysis with varimax rotation. The results generally yielded a rationally interpretable, robust set of factors. ANOVA results on these factors indicated evolutionarily predicted sex differences, particularly with regard to the Intimacy/Warmth dimension. Females scored themselves higher on Intimacy/Warmth than males and rated this characteristic as more important in an ideal friend and an ideal leader than did males. In general, ideal leaders were expected to be higher than ideal friends in scales intended to tap variation in physical attractiveness, intelligence, conscientiousness, activity and sociability and lower in emotionality and disabilities—traits which may well be important in a leader; ideal friends, on the other hand were expected to be higher than prospective leaders in athletic ability and Intimacy/Warmth—traits which are presumably more important for a successful friendship.

What do Children Want? A Conceptualisation of Evolutionary Influences on Children's Motivation in the Peer Group

This paper presents an evolutionary perspective on childrens resourcedirected behaviour in peer groups. It is argued that reciprocity is theoretically expected to be the fundamental rule of resource exchange in peer relationships of friendship. Children are therefore expected to be attracted to peers who are similar to themselves on a wide variety of traits. These traits are viewed as resources in peer relationships, and individual differences in these traits represent a resource environment for children. In this paper, the resource environment represented by individual differences in several evolved motivational systems will be emphasised. The discussion focuses on such three evolved systems, the sensation seeking/impulsivity system, the human affectional system, and the behavioural inhibition system. It is concluded that individual differences in these systems are important for understanding friendship and sociometric status in childrens peer relationships.

Early experience, relative plasticity, and cognitive development

Abstract This paper examines the roles of early experience and relative plasticity in the cognitive development of animals and humans. It is concluded that: (a) long-term effects of early experience variables can be found in the animal and human literature; (b) there are age differences in the relative susceptibility to environmental influences during development; (c) despite qualitative differences in the mechanisms underlying the dependent variables studied in the early experience literature, there are generally applicable principles involving the intensity of environmental stimulation and the buffering ability of the organism which are crucial in affecting the outcome of organism-environment interactions; (d) a variety of models is required to adequately describe the mediation of environmental effects in the early experience literature.