Does opportunistic testing bias cognitive performance in primates? Learning from drop-outs

• Michèle N. Schubiger ,

  Roles Conceptualization, Formal analysis, Investigation, Methodology, Visualization, Writing – original draft, Writing – review & editing

  * E-mail: michele.schubiger@uzh.ch, mnschubiger@gmail.com

  Affiliations Department of Anthropology, Evolutionary Cognition Group, University of Zurich, Zurich, Switzerland, School of Social and Health Sciences, Division of Psychology, Abertay University, Dundee, Scotland, United Kingdom

  http://orcid.org/0000-0002-5707-9691

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• Alexandra Kissling,

  Roles Investigation

  Affiliation Department of Anthropology, Evolutionary Cognition Group, University of Zurich, Zurich, Switzerland

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• Judith M. Burkart

  Roles Conceptualization, Formal analysis, Methodology, Writing – review & editing

  Affiliation Department of Anthropology, Evolutionary Cognition Group, University of Zurich, Zurich, Switzerland

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