INTRODUCTION

The scientific study of imitation in primates dates back to the beginning of the century. Several scholars investigated the question of imitation in monkeys and apes using various experimental approaches such as puzzle boxes. While some of these early researchers claimed to have observed genuine cases of imitation (Hobhouse, 1901; Haggerty, 1909; Witmer, 1909; Furness, 1916), others maintained that the evidence was weak or nonexistent (Thorndike, 1901; Watson, 1908). As a consequence, whether or not primates were capable of learning by means of imitation remained a controversial and largely unresolved issue.

After a period of approximately 80 years in which little empirical research was conducted (see Tomasello & Call, 1997, for a review), the question of imitation has arisen with new force. In recent years, a number of studies of imitation have been conducted on capuchin monkeys, macaques, baboons, chimpanzees, and orangutans. While several studies have indicated that some species of monkeys do not seem to imitate (Beck, 1972, 1973; Chamove, 1974; Visalberghi & Fragaszy, 1990), whether or not chimpanzees and orangutans imitate is still an open question.