Research Seminar: Primate Linguistics (DEC B42)
Spring 2013, Ecole Normale Supérieure
- One 2 hour session a week, during 6 weeks
- Location: Room “INFO 1”, Ecole Normale Supérieure, 45 rue d’Ulm, 75005 Paris
Note: The seminar will be given in English.
Topic: Five striking results have emerged from studies of the vocalizations of non-human primates in the last thirty years.
1. Alarm calls sometimes have a referential semantics, i.e. they do not always encode a *level* of threat, but sometimes the *kind of predator* that triggers their occurrence (the species investigated include: vervet monkeys, Campbell's monkeys, Diana monkeys, among other; a pioneering article was Seyfarth and Cheney 1980). To give an example, Campbell's monkeys have a 'hok' alarm call which is usually used in the presence of eagles, while another alarm call, 'krak', is more commonly associated with leopards (Ouattara et al., PNAS, 2009b).
2. In some cases, a simple morphological structure appears to be available. Thus Campbell's monkeys have an '-oo' suffix which can appear after 'hok', 'krak' and 'wak' and appears to modify their meanings in what *might* be a regular way; in particular, the -oo modified calls appear to be used in situations of less immediate danger than the unmodified versions; and the 'krak-oo' call appears to function as a general alarm call (Ouattara et al., PNAS, 2009a).
3. Several systems of primate vocalizations display syntactic regularities, though few are understood. As a first approximation, it appears that the relevant 'languages' can be generated by finite state machines (with numerous instances of repetitions that are suggestive of 'loops'). A few rules are understood in somewhat greater detail, however. For instance, in Cambpell's monkeys a single 'boom boom' pair can appear at the beginning of a sequence, but virtually never elsewhere – and unlike other calls it cannot be repeated (Ouattara et al., PNAS 2009b).
4. Some syntactic modifications appear to have a regular semantic effect. In particular, the 'boom boom' pair that appears at the beginning of some Campbell's monkey vocalizations seems to indicate the context is not one of predation.
5. Finally, there are intricate cases of cross-species communication in non-human primates. For instance, although Diana monkeys have very different vocalizations from Campbell's monkeys, it was shown experimentally that they understand some of their vocalizations (and vice versa). Strikingly, even though they react with alarm when some Campbell's monkey vocalizations indicative of predators are played back, this anxiety disappears when the 'boom boom' prefix is added to them.
While we do not believe that enough is known about primate vocalizations to establish what relation, if any, they bear to human language, we are convinced that primatologists have described them in such detail that they are ripe for the kind of rigorous modelizations developed in contemporary formal linguistics – hence the term 'primate linguistics'. Students will be encouraged to embark on simple formal analyses of (what is known of) the vocalizations of several non-human primates. While many extant descriptions concern monkeys, we will also discuss recent work on ape communication – including bonobo vocalizations and chimpanzee and gorilla gestures.