“…All primates had participated previously in multiple psychological experiments involving the computerized test system used in this study (e.g., Beran, 2006, 2008; Beran, Evans, Klein, & Einstein, 2012; Beran & Parrish, 2013; Beran & Smith, 2011; Beran & Washburn, 2002; Evans & Beran, 2012, 2014; Evans, Perdue, Parrish, & Beran, 2014; Klein, Evans, Schultz, & Beran, 2013). All chimpanzees had some experience in working on computerized mazes that looked different from the present mazes but that still involved moving to a goal on a computer screen (Fragaszy et al, 2003, 2009).…”