Social learning of vocal structure in a nonhuman primate?

BMC Evolutionary Biology

Klaus Zuberbhler¹  Alban Lemasson²  Karim Ouattara³  Eric J Petit⁴ 

[1] Centre Suisse de Recherches Scientifiques, Ta Monkey Project, Abidjan 01, Cte dIvoire;Ethologie Animale et Humaine, UMR 6552 - CNRS, Universit de Rennes 1, Paimpont, France;Institut Universitaire de France, Paris, France;Laboratoire de zoologie et biologie animale, Universit de Cocody-Abidjan, Abidjan 10, Cte dIvoire

关键词: Nonhuman Primate;    Genetic Relatedness;    Call Variant;    Vocal Behavior;    Contact Call;   

DOI  :  10.1186/1471-2148-11-362

学科分类：生物科学（综合）

来源: BioMed Central

【 摘 要 】

Non-human primate communication is thought to be fundamentally different from human speech, mainly due to vast differences in vocal control. The lack of these abilities in non-human primates is especially striking if compared to some marine mammals and bird species, which has generated somewhat of an evolutionary conundrum. What are the biological roots and underlying evolutionary pressures of the human ability to voluntarily control sound production and learn the vocal utterances of others? One hypothesis is that this capacity has evolved gradually in humans from an ancestral stage that resembled the vocal behavior of modern primates. Support for this has come from studies that have documented limited vocal flexibility and convergence in different primate species, typically in calls used during social interactions. The mechanisms underlying these patterns, however, are currently unknown. Specifically, it has been difficult to rule out explanations based on genetic relatedness, suggesting that such vocal flexibility may not be the result of social learning. To address this point, we compared the degree of acoustic similarity of contact calls in free-ranging Campbell's monkeys as a function of their social bonds and genetic relatedness. We calculated three different indices to compare the similarities between the calls' frequency contours, the duration of grooming interactions and the microsatellite-based genetic relatedness between partners. We found a significantly positive relation between bond strength and acoustic similarity that was independent of genetic relatedness. Genetic factors determine the general species-specific call repertoire of a primate species, while social factors can influence the fine structure of some the call types. The finding is in line with the more general hypothesis that human speech has evolved gradually from earlier primate-like vocal communication.

【 授权许可】

CC BY