INTRODUCTION

Is the intelligence of monkeys and apes primarily a “Machiavellian” adaptation for social life, an ecological adaptation for resource exploitation, or both a social and an ecological adaptation? How can we evaluate these competing models of intelligent adaptation? Are great apes really smarter than monkeys? How can we assess the cognitive complexity of social life? Are the social organizations and/or social roles of great apes more complex than those of monkeys? If they are, do different developmental and acquisition processes underlie that greater complexity, and which models are useful for studying those processes? Similarly, how is socioecological knowledge distributed and transmitted from one generation to the next, and what models are useful for studying this process? All these questions plague efforts to characterize great ape cognition and to reconstruct its evolution.

Systematic evaluation of social and/or ecological hypotheses about primate cognition calls for an integrated framework for comparing the sophistication of social organization and socialization in wild primates. Despite keen interest in specific topics in social cognition (e.g., social learning, social communication), a comprehensive ecologically based framework for comparing primate social cognition is currently lacking.

In this chapter, I propose such a framework. Specifically, this comparison can be made in terms of (1) the number, function, and composition of activity subgroups within primate range groups; (2) the social roles the members of these activity subgroups play; and (3) the typical routines or scripts in which these roles are played.

The collection of articles herein focuses on the mysterious liminal region that lies between pre-symbolic and symbolic abilities. The transition between the two remains the least charted area, most intriguing of all developmental transformation in human childhood, and the least understood of all transformations in hominoid evolution. The mystery is deepened by disagreements over terminology. Simulation, imitation, pretense, symbolic play, representation, meta-representation, theory of mind, intentionality, and imagination, the very definition of these terms is contested territory. Authors of articles in this volume do not simplify the task because many of them disagree on these matters. Rather, their articles provide readers with a fascinating array of perspectives on these and related concepts. They also provide comparative data on a rich array of great ape species: humans, bonobos, chimpanzees, gorillas, and orangutans, plus some macaque monkeys.

Following in the wake of his earlier work on deception, self-awareness, and anthropomorphism, Robert Mitchell's new collection carries us further into contested twilight zones between infancy and childhood, and between other great ape and human minds. The juxtaposition between animals and children in the title is more than accidental since many of the same frameworks have been used to study and compare children of our species with those of our closest living relatives, the nonhuman great apes, an approach that has come to be known as comparative developmental evolutionary psychology (Parker, 1990).

The title The mentalities of gorillas and orangutans: Comparative perspectives was inspired by Köhler's famous book The mentality of apes (1927), in which apes were implicitly equated with chimpanzees. This book focuses on two other great apes that were less known in Köhler's day. It is the fourth in a related series of edited volumes on cognition of great apes. The first volume, “Language” and intelligence in monkeys and apes (Parker & Gibson, 1990), emphasized the importance of using models from developmental psychology to compare the cognitive and symbolic abilities of monkeys, apes, and humans. The second volume, Self-awareness in animals and humans (Parker, Mitchell, & Boccia, 1994), used developmental frameworks to compare manifestations of self-awareness in monkeys, apes, and humans. It was aimed at broadening the scope of research in this subject to extend beyond the classical mark test for mirror self-recognition. The third volume, Reaching into thought (Russon, Bard, and Parker, 1996), focused on cognitive abilities of great apes using models from developmental psychology, but extended the scope to include studies in wild populations. This most recent volume continues the tradition of using models from developmental psychology to compare the cognitive abilities of great apes, and that of including studies from both captive and wild populations. It also expands the preview to include studies of taxonomy and phylogeny (Begun, this volume) and the brain (Semendeferi, this volume). It differs from the other volumes in focusing primarily on gorillas and orangutans. The aim of this volume is to redress the chimpocentric imbalance in attention to chimpanzees and bonobos at the expense of the other great apes.