How much does cognition influence variation in chimpanzee vocal production?
In stark contrast to human speech, animal signals are thought to be tied to emotional states and hence tied to fixed social and ecological contexts that precipitate certain emotions. This leaves 1) little flexibility in signal production within contexts, and 2) little cognitive influence on signal production. I will present new empirical data from our closest living relatives, the chimpanzee, suggesting that these assumptions are premature. I will show variation of call usage across chimpanzee populations, suggesting potential for call ‘cultures’. I also will use evoultionary theory and empirical data to suggest evolutionary drivers of call diversity.
Dr. Crockford started out as a clinician working with acquired speech and language disorders, and then became a primatologist in 2000 and a group leader in 2012 at the Max Planck Institute for Evolutionary Anthropology in Leipzig. She studies the evolution of speech and language, and likely interlinked, the evolution of sociality, in two subspecies of wild chimpanzees in the Ivory Coast and in Uganda.