Humans can recognise behavioural contexts from chimpanzees’ vocalizations

A new study shows that humans can infer specific information when genetically closely related species verbally express emotions. In an experiment including over 3000 human listeners judging 155 vocalizations of 66 chimpanzees, the participants were able to accurately infer behavioural contexts like threat, play, and food. Researchers from the University of Amsterdam, the University of York and the Max Planck Institute for Evolutionary Anthropology in Leipzig, provide evidence that human listeners can infer the behavioural context in which chimpanzee vocalisations were produced, such as being attacked by another chimpanzee and discovering a large food source, and can correctly judge arousal (excitement), and valence (positive and negative). The results of their study are now published in Proceedings of the Royal Society B. Background of the study. When we hear a cat hissing, a dog barking, or a person laughing, we infer information from these vocalisations about the affective state of the individual and the kind of situation they are in. From earlier studies we already know that humans can accurately infer arousal and emotional valence from vocalisations of many different species. There are also some studies that tested if human listeners are able to recognise behavioural contexts from vocalisations, like discovering food. These studies showed that listeners can indeed correctly classify the production context of dogs' barks, cats' meows, and the vocalisations of pigs. However, these studies are all limited to domesticated animals that are distantly related to humans. Kamiloglu et al. now examined the ability of human listeners to infer behavioural context in addition to arousal (excited, relaxed) and emotional valence (positive, negative) from vocalisations of chimpanzees, one of the genetically closest living relatives to humans. Testing two hypotheses in two experiments