Population-Specific Use of the Same Tool-Assisted Alarm Call between Two Wild Orangutan Populations (Pongopygmaeus wurmbii) Indicates Functional Arbitrariness

• Adriano R. Lameira ,

  * E-mail: adriano@orangutan.nl

  Affiliations Animal Ecology, Utrecht University, Utrecht, The Netherlands, Pongo Foundation, Oudewater, The Netherlands

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• Madeleine E. Hardus,

  Affiliations Pongo Foundation, Oudewater, The Netherlands, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands

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• Kim J. J. M. Nouwen,

  Affiliations Animal Ecology, Utrecht University, Utrecht, The Netherlands, Adaptation Physiology Group, Wageningen University, Wageningen, The Netherlands

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• Eva Topelberg,

  Affiliations Animal Ecology, Utrecht University, Utrecht, The Netherlands, Adaptation Physiology Group, Wageningen University, Wageningen, The Netherlands

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• Roberto A. Delgado,

  Affiliation Human and Evolutionary Biology, University of Southern California, Los Angeles, California, United States of America

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• Berry M. Spruijt,

  Affiliation Animal Ecology, Utrecht University, Utrecht, The Netherlands

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• Elisabeth H. M. Sterck,

  Affiliations Animal Ecology, Utrecht University, Utrecht, The Netherlands, Biomedical Primate Research Center, Rijswijk, The Netherlands

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• Cheryl D. Knott,

  Affiliation Department of Anthropology, Boston University, Boston, Massachusetts, United States of America

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• Serge A. Wich

  Affiliation Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, United Kingdom

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