Orangutans have larger gestural repertoires in captivity than in the wild-A case of weak innovation?
Marlen Fröhlich, Natasha Bartolotta, Caroline Fryns, Colin Wagner, Laurene Momon, Marvin Jaffrezic, Tatang Mitra Setia, Caroline Schuppli, Maria A van Noordwijk, Carel P van Schaik
Author Information
Marlen Fröhlich: Department of Anthropology, University of Zurich, 8057 Zurich, Switzerland.
Natasha Bartolotta: Department of Anthropology, University of Zurich, 8057 Zurich, Switzerland.
Caroline Fryns: Department of Anthropology, University of Zurich, 8057 Zurich, Switzerland.
Colin Wagner: Département Ecologie, Physiologie et Ethologie, University of Strasbourg, 67037 Strasbourg, France.
Laurene Momon: Département Ecologie, Physiologie et Ethologie, University of Strasbourg, 67037 Strasbourg, France.
Marvin Jaffrezic: Département Ecologie, Physiologie et Ethologie, University of Strasbourg, 67037 Strasbourg, France.
Tatang Mitra Setia: Fakultas Biologi, Universitas Nasional, 12520 Jakarta Selatan, Indonesia.
Caroline Schuppli: Department of Anthropology, University of Zurich, 8057 Zurich, Switzerland.
Maria A van Noordwijk: Department of Anthropology, University of Zurich, 8057 Zurich, Switzerland.
Carel P van Schaik: Department of Anthropology, University of Zurich, 8057 Zurich, Switzerland.
Whether nonhuman species can change their communicative repertoire in response to socio-ecological environments has critical implications for communicative innovativeness prior to the emergence of human language, with its unparalleled productivity. Here, we use a comparative sample of wild and zoo-housed orangutans of two species () to assess the effect of the wild-captive contrast on repertoires of gestures and facial expressions. We find that repertoires on both the individual and population levels are larger in captive than in wild settings, regardless of species, age class, or sampling effort. In the more sociable Sumatran species, dominant use of signals toward single outcomes was also higher in captive settings. We thus conclude that orangutans exposed to more sociable and terrestrial conditions evince behavioral plasticity, in that they produce additional innate or innovated signals that are highly functionally specific. These findings suggest a latent capacity for innovativeness in these apes' communicative repertoires.
