Origins of the Social Mind
Evolutionary Psychology and Child Development
Edited by Bruce J. Ellis and David F. Bjorklund
Part I: Conceptual Foundations of Evolutionary Developmental Psychology: Core Issues and Approaches
Evolutionary Psychology and Child Development: An Emerging Synthesis, David F. Bjorklund and Bruce J. Ellis
Evolutionary developmental psychology is emerging as a new field, the result of the integration of data, theory, and much thought from mainstream developmental and evolutionary psychology. However, the resulting product is neither the average nor the sum of the two parent disciplines, but a unique perspective that nonetheless is compatible with the major tenets of both developmental and evolutionary psychology. We argue that developmental psychology can greatly benefit from taking an evolutionary perspective without falling into the "trap" of implicit nativism that some developmentalists attribute to evolutionary thinking. Similarly, we contend that evolutionary psychology can benefit from paying more explicit attention to the role of gene-environment interactions, beginning very early in life, without altering its central focus on explaining the behavior of contemporary people in terms of evolved cognitive mechanisms for solving recurrent adaptive problems faced by our ancestors.
Evolution of the Human Child, Mark Flinn and Carol Ward.
The human child is an extraordinary organism, possessed of an enormous, costly brain and yet physically helpless. This condition of dependency, moreover, persists for a long period relative to other mammals. The selective pressures responsible for these unusual life history characteristics appear central to understanding human evolution. Evidence from the fossil record is consistent with the hypothesis that conspecific social competition was the primary selective pressure shaping the uniquely human combination of physically altricial but mentally and linguistically precocial infancy, extended childhood, and extended adolescence, enabled by extensive bi-parental and kin care.
The Role of Developmental Plasticity in Human Cognitive Evolution, David F. Bjorklund and Justin S. Rosenberg
This chapter applies the developmental systems approach to evolution, examining the role that behavioral plasticity early in ontogeny may have in producing species-level changes in behavior and cognition. The focus is on human cognitive evolution, with the examination of how the confluence of big brains, an extended juvenile period, and social complexity contributed to the pattern of changes that produced Homo sapiens. We argue that research on enculturated (human-reared) great apes can provide an experimental means of assessing the role that behavioral plasticity and species-atypical environments may have had in human cognitive evolution.
Early Stress: Perspectives from Developmental Evolutionary Ecology, James S Chisholm, Victoria K Burbank, David A Coall, and Frank Gemmiti
This chapter is about life history theory - the developmental evolutionary ecology of life cycles. We begin with an overview of biology's adaptationist and mechanist schools to show that evolutionary theory is incomplete without a theory of development (and vice versa) and to justify our focus on the development of alternative reproductive strategies. We then review principles of life history theory and evolutionary ecology to show why environmental risk and uncertainty are expected to be major determinants of alternative reproductive strategies and why they must be represented phenotypically, literally embodied, to have their adaptive effect. Turning to the mechanist perspective, we briefly review arguments that the attachment process and accompanying endocrine processes are good candidate mechanisms for entraining the development of alternative reproductive strategies contingent on early environmental risk and uncertainty, mortality rates in particular. We conclude that viewing life cycles as alternative reproductive strategies suggests that insecurity - in the form of insecure internal working models and/or the psychoneuroendocrine consequences of insecurity - is mediated by the attachment process.
Developmental Behavioral Genetics and Evolutionary Psychology: Tying the Theoretical and Empirical Threads, Nancy L. Segal and Elizabeth Hill
Behavioral genetics and evolutionary psychology have had little exchange over the years, but there are areas of common interest. Behavioral-genetic methods can be used to test a variety of evolutionary-based hypotheses concerning human behavioral and physical development. In addition, evolutionary reasoning informs developmental behavioral genetics (DBG). A number of twin studies, using the classic design and variants of that design, have tested a variety of behavioral phenotypes of interest to evolutionary psychologists,. e.g., cooperation, competition and altruism. Understanding the interplay between genes and environment over time will be a major task for evolutionary developmental psychology. Several steps can be taken to advance the field in this direction. Some include greater use of experimental studies of non-human animals, more use of family and sibling designs to augment the classic MZ-DZ twin comparison, and additional research on gene- behavior associations using a molecular-genetic framework..
Part II: Personality and Social Development
Differential Susceptibility to Rearing Influence: An Evolutionary Hypothesis and Some Evidence, Jay Belsky
Central to evolutionary theory is the notion that natural selection shapes organisms in the service of maximizing reproductive fitness. In view of the fundamentally uncertain nature of the future, parents could not have known in ancestral times whether their efforts to foster developmental outcomes presumed to promote reproductive success would in fact do so. It is argued, therefore, that that it would have been in parents (and children's) reproductive best interests for children to vary in their susceptibility to parental rearing, and so natural selection would have shaped parent-child relations so that some children were less and others more susceptible to rearing influence. This bet-hedging strategy in the face of an uncertain future would reduce the risk of children being shaped by parents in ways that ultimately proved to undermine, or at least not maximize, the reproductive success of parent and child in the event that the future turned out rather differently than parents (consciously or unconsciously) anticipated. Evidence is reviewed suggesting that children do indeed vary in their susceptibility to rearing influence and, intriguingly, that highly negative infants may be more susceptible to effects of rearing than other infants.
Determinants of Pubertal Timing: An Evolutionary-Developmental Approach, Bruce J. Ellis
Pubertal maturation is a dynamic biological process--punctuated by visible changes in stature, body composition, and secondary sexual characteristics--that culminates in the transition from the prereproductive to the reproductive phase of the human life cycle. Although hundreds of studies within the fields of psychology, biology, and medicine have examined antecedents of pubertal development in girls, no overarching theoretical framework has integrated, united, or subsumed this large and variegated literature. In this chapter I endeavor to show that an evolutionary life history approach not only provides a powerful framework for connecting and organizing extant theory and data on determinants of pubertal timing, but that it also suggests new hypotheses and lines of research to be followed. Particular attention is paid to sources of variation in pubertal timing (environmental and genetic), and to evaluation of competing hypotheses concerning the nature, extent, and direction of environmental influences on puberty.
Sex Differences in Competitive and Aggressive Behavior: A View from Sexual Selection Theory, Anthony Pellegrini and John Archer
An exploratory model that is rooted in Darwin's sexual selection theory for the development of sex differences in agonistic behavior is presented. We examine the dynamic relations between social experiences and evolutionary forces and how they relate to sex differences in agonism, or competitive and aggressive behaviors. We first outline basic tenets of sexual selection theory and parental investment theory with a focus on agonism and to the importance of sex segregation as a developmental context for sex differences in agonism. Next we specify the dynamic relations between evolutionary history and the context in which individuals develop. Third, we present evidence for a model of sex differences in both sex segregation and agonistic behavior. The model posits that mating systems and resources (in the form of nutrition) influence each other and affect sexual dimorphism in size and levels of sex segregation. In segregated groups, males exhibit high levels of vigorous and competitive behavior, as they sort out dominance relationships and maximize their physical conditioning. Agonistic behavior in male groups is characterized by competitive dominance-related encounters and by physical aggression.
Play: Types and Functions in Human Development, Peter K Smith
This chapter summarizes the main kinds of play in human children, and gives a brief historical overview of research, mentioning the influence of the 'play ethos'. More detailed description is then given of the phylogeny and ontogeny of physical activity play, rough-and-tumble play, object play, and pretend play. Given the near- universality of the various forms of play, its costs (time, energy) and the robust developmental mechanisms involved (e.g., hormonal influences on rough-and- tumble play; peer and parental influences), we can expect there to be benefits to playing. These probably vary for the different kinds of play, but may include (respectively) physical training and endurance; practice in fighting skills and establishing and maintaining dominance; practice in object skills related to subsistence activities and problem-solving; and practice in advanced social- cognitive skills such as theory of mind.
Social Behavior and Personality Development: The Role of Experiences with Siblings and with Peers, Judith Rich Harris
To account for findings on environmental influences on personality, the author proposes that the child's mind is equipped with two separate mental mechanisms for making long-term adjustments of social behavior on the basis of experience. These mechanisms provide different goals, are responsive to different environmental cues, and process the information in different ways. The socialization mechanism motivates children to behave like typical members of their age and gender category; it is responsive to social cues related to acceptance. The behavioral strategy mechanism collects information that tells children how they compare with others of their age and gender; it is responsive to social cues related to status. This second mechanism creates or maintains individual differences in social behavior and is the source of most of the nongenetic variation in personality. The goal of the behavioral strategy mechanism -- to be best -- sometimes conflicts with the goal of the socialization mechanism- to conform. The evidence suggests that these mechanisms make long-term adjustments of social behavior primarily on the basis of information collected outside the family.
Some Functional Aspects of Human Adolescence, Glenn E. Weisfeld and Heather C. Janisse
This chapter constitutes an essay into the still largely atheoretical field of human adolescence. A framework, or context, is needed for understanding normal human adolescence and its pathological variants. General, incontrovertible statements about adolescence will provide this functional framework. Basic features of human adolescence are those bodily and behavioral traits with an evolved basis. These are identified by, for example, establishing the trait's universality, hormonal basis, stereotypy, or presence in related species. Once an evolved trait is identified, its function can be investigated. A hypothesized functional explanation is usually tested by determining whether or not it accounts precisely for the trait's distribution in the animal kingdom, e.g., female mammals of reproductive age. Comparative research has identified many universals in adolescent behavior and shown how they enhance individual fitness. In addition, cultural practices can often be analyzed functionally, since these too tend to enhance fitness. This chapter describes some patterns and functional principles of pubertal development, puberty rites, the adolescent's family context, peer competition, and mate choice.
Evolutionary Origins and Ontogenetic Development of Incest Avoidance, Irwin Silverman and Irene Bevc
This chapter approaches the origins of incest avoidance from the standpoint of both phylogenetic and ontogenetic development. Pure cultural theories are described and their inadequacies noted. In support of an evolutionary perspective, evidence is presented for the universality of incest avoidance across both human societies and infrahuman species. The presumed adaptive functions of incest avoidance are also described, both in terms of maintaining diversity in the gene pool and avoiding inbreeding depression. Finally, the various mechanisms by which incest avoidance develops and is expressed, within species, are depicted. In this vein, the primary mechanism for humans is. considered to be continuous proximity and association during an early critical period in childhood, leading to later mutual sexual aversion. Historical and contemporary studies bearing on the operation of this mechanism are discussed.
Part III: Cognitive Development
Infant Perception and Cognition: An Evolutionary Perspective on Early Learning, David Rakison
The adaptive problems facing the human infant's perceptual and cognitive systems, and presumably that of the young of other species, are to make sense of a multitude of information rapidly and in a veridical manner. In this chapter, a broad literature on perceptual and cognitive development in infancy is reviewed, including depth perception, shape and size perception, face perception, movement and object perception, causal perception, na´ve physics, na´ve mathematics, and object category and concept formation. The overarching aim of the review is to determine whether there is evidence in these domains of enquiry for evolved specialized psychological mechanisms or more general all-purpose ones (e.g., conditioning, associative learning). The review suggests that infants possess both domain-general and domain-specific mechanisms. Specifically, it is suggested that domain-general mechanisms operate for information that is highly structured in the environment and has remained consistent over phylogenetic time (e.g., object physics, object category formation). Domain-specific mechanisms, in contrast, operate for information that is not as highly structured in the environment and/or that is relevant for survival and reproduction (e.g., face perception, depth perception).
Evolution and Development of Human Memory Systems, Katherine Nelson
The evolution of human memory is considered as a functional cognitive system emerging through co-active processes of dynamic developmental systems. Levels and kinds of memory are distinguished as characteristic of different evolving species. Tulving's distinction among procedural, semantic and episodic memory, the last assumed to be unique to humans, is discussed and related to the late emergence in childhood of evidence for episodic memory and the development of autobiographical memory. Donald's proposal of major transitions in memory over the course of evolution and later human history forms the basis for discussion of specific transitions in the development of cognitive levels and memory types in childhood. It is concluded that basic forms of memory are involved in event memory and imitation in late infancy, and that episodic memory and language- dependent memory entering into autobiographical memory, as well as the use of external memory in literate societies emerged from biological and cultural co- evolution processes and in development from the experience of remembering as human social and cultural practices.
The Empathizing System: A Revision of the 1994 Model of the Mindreading System, Simon Baron-Cohen
The model of the Mind-Reading System (Baron-Cohen, 1994) proposed the existence of 4 distinct neurocognitive mechanisms (the Intentionality Detector [ID], the Eye Direction Detector [EDD], the Shared Attention Mechanism [SAM], and the Theory of Mind Mechanism [ToMM]) as key in the development of human social cognition. In this chapter, this model is reviewed using the framework of 'empathy' and is found lacking, as emotion has no place in the 1994 model. This omission is rectified in the revision of the model, presented here. In particular, The Emotion Detector [TED] is added, as a perceptual mechanism, and The Empathizing SyStem [TESS] is also included, as a reactive mechanism. It is argued that the inclusion of these two new components are needed in order to help distinguish between different forms of psychopathology, such as autism and psychopathy. The evolutionary bases of the Mind-Reading System are discussed, as are sex differences in empathizing (female advantage) and systemizing (male advantage), not only for their evolutionary significance, but also in the light of new evidence that autism might be an extreme of the male brain.
Cognitive Development and the Understanding of Animal Behavior, H. Clark Barrett
Animals are unlike other classes of objects in the world in that they are intentional agents: they process information and are capable of goal-directed action, and therefore obey causal principles that inanimate objects do not obey. The ability to make appropriate inferences and decisions with respect to non-humans animals had important consequences for survival and reproduction over the course of human evolution, particularly in the contexts of predator avoidance and hunting. For these reasons, humans have evolved a variety of mechanisms for detecting, categorizing, and making inferences about animals as intentional agents. This system of cognitive mechanisms, which I call the agency system, is what underlies our understanding of animal behavior and what guides its development in childhood. In this chapter, I survey a variety of features of the agency system that are relevant to cognitive development and the understanding of animal behavior, from perceptual mechanisms, to knowledge acquisition, to reasoning and decision-making about animals.
Folk Knowledge and Academic Learning, David C. Geary
Among the central goals of evolutionary psychology are to identify evolved systems of folk knowledge and to determine the developmental mechanisms through which the cognitive and social competencies that compose these domains are adapted to the local social group and wider ecology. A taxonomy of evolved cognitive domains that coalesce around in the areas of folk psychology, folk biology, and folk physics is presented, along with a model for conceptualizing motivational biases, and children's inherent developmental activities that adapt these folk domains to the local conditions. Implications for children's learning of culture-specific academic competencies, such as reading, and associated motivational and instructional issues are then discussed. The thesis is that the cognitive, motivational, and developmental systems that compose folk knowledge are not sufficient for academic learning, but are the foundation from which academic competencies are built. A broad outline of how folk knowledge might be adapted for academic learning is provided, as is related discussion concerning children's motivation to learn in school. Implications for educational theory and research are profound.
Language Evolution and Human Development, Brian MacWhinney
Language is a unique hallmark of the human species. Although many species can communicate in limited ways about things that are physically present, only humans can construct a full narrative characterization of events occurring outside of the here and now. The evolution of this ability has relied on a gradual evolution of cognitive and social abilities, first in our primate cousins, then in our hominids ancestors, and finally in modern humans. The movement to a bipedal posture triggered a variety of further development involving tool use, spatial navigation, and gestural communication. New social structures benefited from increasing vocal and gestural communication. More recently, changes in vocal and neural physiology led to the development of systematized language and the recursive processing of lexical items. Once humans could combine words into sentences, they could use syntax to mark the shifts of perspective between actors. These changes were reflected in the "creativity explosion" of Neolithic times.
The Evolutionary History of an Illusion: Religious Causal Beliefs in Children and Adults, Jesse M. Bering
The capacity to represent unseen, intentional causal forces as being responsible for unexpected events that are related to the self (e.g., "why me?") appears to be a central feature of both formal and informal religious beliefs. The representational processes necessary for such attributions are likely highly complex, grounded in social cognitive functions such as teleology, intentionality, theory of mind, referential communication, and the development of the self system. Recent experimental approaches in the field of evolutionary developmental psychology have focused on the ontogenetic emergence of specific cognitive abilities that are related to religious causal beliefs. The author argues that these developmental data are beginning to reveal an organized structure, and perhaps even an adaptive design, underlying such beliefs. In particular, an existential meaning system may have evolved in order to promote genetic fitness-enhancing behaviors among ancestral individuals who were forced to cope with selfish desires in the face of punitive moral societies.