Meaningful Communication in Primates, Birds, and Other Animals

Communication plays a role, and sometimes a major role, in almost all aspects of behavior that have to do with higher cognition in animals. Research in this area has usually concentrated on several distinct topics, these being memory, problem solving, learning, using tools, concept formation and categorization, referential signaling, inferring the state of another, and even engaging in hunting. Debates on the cognitive abilities of apes have dominated the last decade and have been the impetus for a substantial volume of research and innovative writing (e.g., Byrne, 1995; Byrne and Whiten, 1988; Carruthers and Smith, 1996; Harcourt, 2000; Heyes, 1998; Heyes and Huber, 2000; Parker and Gibson, 1990; Gibson and Ingold, 1993; Russon et al., 1996; Sternberg and Kaufman, 2002 ). Many experiments conducted with chimpanzees, gorillas, and orangutans have since underscored the belief that great apes have higher cognitive abilities, but the view that these might be unique to great apes amongst animals has become increasingly doubtful. This chapter is focused on two topics: referential signals and communication associated specifically with hunting. The two topics for discussion are chosen advisedly. Finding evidence of referential signaling in any species is deemed to be an important step in demonstrating intentional communication that has to be more than, or different from, expressing affect. Since referential signaling was first discovered ill primates, much has been written about the topic. Referential signals, such as alarm calls, are relatively simple vocal forms of communication but they have gained significance in so far as they have been regarded, by some researchers, as rudimentary forms of language (concept formation). Referential signaling can occur between two individuals, whereas the examples of hunting that will be discussed here are group activities of more than two individuals. Although animals can hunt alone or in pairs, the evidence of higher cognition is related particularly to group activities and, of course, hunting requires some form of coordination. By comparison with the recent research interest in referential signals, investigations of the link between hunting and higher cognition has been relatively underrepresented. Nevertheless, there is a continued and abiding interest in hunting and meat eating by chimpanzees and what these might entail in terms of cognition and communication. Also, especially in the literature on whales and dolphins, there is mounting research evidence tor behavioral complexity in hunting, involving communication and higher cognition (Boran and Heimlich, 1999).