Chimpanzee calls differ according to context

[Judi Lynn]

May 23, 2018, Max Planck Society

An important question in the evolution of language is what caused animal calls to diversify and to encode different information. A team of scientists led by Catherine Crockford of the Max Planck Institute for Evolutionary Anthropology found that chimpanzees use the quiet 'hoo' call in three different behavioural contexts—alert, travel and rest. The need to stay together in low visibility habitat may have facilitated the evolution of call subtypes.

Studies examining animal alarm calls suggest species which require different escape responses for different predators are more likely to have correspondingly different alarm calls, facilitating appropriate escape responses from receivers. However, what causes calls to diversify in less urgent contexts is little examined. "To address this, we examine a quiet contact vocalisation of chimpanzees, the 'hoo'", says Catherine Crockford of the Max Planck Institute for Evolutionary Anthropology. "We found that chimpanzees have at least three acoustically different 'hoo' variants, each given in a different behavioural context: alert, travel and rest."

Read more at: https://phys.org/news/2018-05-chimpanzee-differ-context.html#jCp