Chimpanzees (Pan troglodytes) Produce the Same Types of ‘Laugh Faces’ when They Emit Laughter and when They Are Silent

• Marina Davila-Ross,

  Affiliation Centre for Comparative and Evolutionary Psychology, Psychology Department, University of Portsmouth, Portsmouth, United Kingdom

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• Goncalo Jesus,

  Affiliation Department of Anthropology, University College London, London, United Kingdom

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• Jade Osborne,

  Affiliation Centre for Comparative and Evolutionary Psychology, Psychology Department, University of Portsmouth, Portsmouth, United Kingdom

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• Kim A. Bard

  * E-mail: kim.bard@port.ac.uk

  Affiliation Centre for Comparative and Evolutionary Psychology, Psychology Department, University of Portsmouth, Portsmouth, United Kingdom

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