INTRODUCTION

Ten years ago, studies of animal behavior had little to say about the existence of “teaching,” despite the years which had elapsed since the innovative attempts of Barnett (1968) and Ewer (1969) to put it on the agenda. In recent years, we have seen a new flowering of interest in the phenomenon in primates – the principal subjects of this chapter – and also in other animals. Descriptions of quite elaborate forms of behavior which have been argued to fit concepts like teaching, encouragement, and discouragement have accumulated in the course of long-term primate field studies (e.g., Van de Rijt-Plooij and Plooij, 1987; Hiraiwa-Hasegawa, 1990; Boesch, 1991) as well as in captive studies (e.g., Fouts, Fouts & Cantfort, 1989). More recently, largely qualititative observations like these have been supplemented by the first substantial quantitative analyses designed not only to describe the phenomena but to test hypotheses about the power of these types of parental behavior to influence infant development (Caro & Hauser, 1992; Maestripieri, 1995a,b, 1996). Caro and Hauser showed that, in conjunction with their own data on felids and primates, by 1992 the accumulation of empirical reports was sufficient to merit the first major review of “teaching in nonhuman animals,” teaching here being defined by its functional consequence of facilitating a juvenile's developmental progress, rather than by any deliberate intention to educate. The great apes contribute some of the most complex and interesting components of this body of evidence and these form the basis of this chapter.