Communicative intentions
Non-human animal communication has been claimed to be restricted to what has been called imperatives; these animals are claimed to be in capable of declaratives, that is, of communicating something for its own sake, simply trying to affect the listener’s mind (see e.g. Baron-Cohen 1992: 149). But what is the communicative intention, for example, of the leopard, eagle, and snake alarm calls of vervet monkeys?
Cheney and Seyfarth (1990, 1992) is a seminal study of the communicative system of vervet monkeys and an important contribution to our understanding of intentionality1 in human communication vs. animal communication. On the basis of this study we know that the vervet monkeys have a repertoire of four distinct calls:
(a) Wrr—usually given when a neighboring group has first been spotted;
(b) snake call—alarm call for snakes;
(c) leopard call—alarm call for leopards;
(d) eagle call—alarm call for eagles.
These calls are phonologically distinct and arbitrary, representational signals which stand for an object even when that object cannot be seen. And they evoke clear reactions: When hearing the leopard call, other vervets on the ground run into trees, on the eagle call they look up or run into bushes, and on the snake call they stand bipedally and peer into the grass around them.
What about the level of intentionality observed in the behavior of vervet monkeys? Cheney and Seyfarth (1990: 139–43) distinguish between the following levels of intentionality and types of intentional systems: (i) zero-order, where there are no beliefs or desires at all; (ii) first-order, where there are beliefs and desires but no beliefs about beliefs; and (iii) second-, third-,or higher-order, where there is some conception about both one’s own and other individuals’ states of mind. Cheney and Seyfarth conclude that the calls of the vervet monkeys are suggestive of first-order intentionality because the monkeys producing these calls want others to run into trees, bushes, etc., but not necessarily of second-order intentionality, in which case they would want others to think that there is a leopard, eagle, or python nearby. Cheney and Seyfarth (1992: 174) furthermore observe that there is no evidence that vervet alarm calls are declarative rather than imperative.
Studies carried out on animals in captivity suggest that by far the most important motivation of animal communication is manipulative rather than declarative—a motivation which Terrace (1985) calls acquisitive: The communicative behavior of the animals is geared primarily at expressing requests.96 percent of the lexigram utterances made by the bonobo Kanzi were interpreted as requests (Greenfield and Savage-Rumbaugh 1990), in Rivas’s (2005) sample on five chimpanzees, 86percent of all utterances were requests (65 percent for objects and 18 percent for actions), and Terrace (1985) also describes chimpanzee signing as being predominantly acquisitive in nature.
But animal communication is not exclusively acquisitive, and some authors (e.g. Gardner and Gardner 1978; Fouts and Mills 1997) even reject the claim that the communicative intentions of their chimpanzees are primarily request-oriented. Greenfield and Savage-Rumbaugh (1990) classified 4 percent of Kanzi’s utterances as being indicatives or statements, and the chimpanzees studied by Rivas (2005) made 4 percent of their utterances to answer questions posed by humans, and 2percent to name or label objects and pictures, while for 8 percent of their utterances the communicative intention was not evident. For the chimpanzee Ally, action requests and naming were the largest categories of speech acts, but almost one-fourth of his communications consisted of other kinds of sign acts (Miles 1978: 113). And signing by the gorilla Koko was not exclusively acquisitive either; it also included comments about the state of the environment, for example when she signed LOOK BIRD to draw attention to a picture of a crane in a stereo viewer, or LISTEN QUIET when an alarm clock stopped ringing in the next room (Patterson 1978a: 87–8).
That the motivations of apes cannot be reduced to being manipulative is also suggested by the observation that chimpanzees were found signing when they were alone, for example looking at pictures in magazines, and the gorilla Koko engaged in imaginative play using signing, or talked to herself by signing what she saw (Patterson 1978b: 191, 195). While the purpose of this signing has not been reconstructed, it is unlikely to have been request-oriented.
1 Intentional phenomena are about some other thing, be it a physical stimulus or another mental state. Whenever an individual thinks, believes, wants, likes, or fears something, s/he is said to be in an intentional state.
