title: Kea cooperate better with sharing affiliates.
abstract: Controlled studies that focus on intraspecific cooperation tasks have revealed striking similarities, but also differences, in abilities across taxa as diverse as primates, fish, and birds. Such comparisons may provide insight into the specific socio-ecological selection pressures that led to the evolution of cooperation. Unfortunately, however, compared to primates data on birds remain relatively scarce. We tested a New Zealand psittaciform, the kea, in a dyadic cooperation task using the loose-string design. During trials our subjects were in separate compartments, but obtained a common reward that could be divided multiple ways, allowing the examination of reward division effects. Ten individuals were tested twice in 44 combinations of partners. Dyads with a high affiliation score attempted to cooperate more often and were also more often successful in doing so. Furthermore, dyads that shared rewards more equally seemed to be more likely to attempt cooperation in the next trial. Like other bird and some monkey species, but unlike, for example, chimpanzees, kea did not spontaneously show understanding of either the role of the partner or the mechanism behind the cooperation task. This may point to true disparities between species, but may also be due to differences in task design and/or the amount of exposure to similar tasks and individual skills of the subjects.
authors.affiliation: Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine, Medical University of Vienna, University of Vienna, Vienna, Austria. raoul.schwing@vetmeduni.ac.at.|Haidlhof Research Station, University of Veterinary Medicine, University of Vienna, Bad Vöslau, Austria. raoul.schwing@vetmeduni.ac.at.
authors.forename: Raoul
authors.identifier: 0000-0003-4663-8432
authors.initials: R
authors.lastname: Schwing
authors.affiliation: Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine, Medical University of Vienna, University of Vienna, Vienna, Austria.|Département Ecologie, Physiologie et Ethologie, IPHC, Strasbourg, France.
authors.forename: Elodie
authors.initials: E
authors.lastname: Jocteur
authors.affiliation: Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine, Medical University of Vienna, University of Vienna, Vienna, Austria.
authors.forename: Amelia
authors.initials: A
authors.lastname: Wein
authors.affiliation: Faculté Psychologie, Université de Strasbourg, Strasbourg, France.
authors.forename: Ronald
authors.initials: R
authors.lastname: Noë
authors.affiliation: Haidlhof Research Station, University of Veterinary Medicine, University of Vienna, Bad Vöslau, Austria. jorg.massen@univie.ac.at.|Department of Cognitive Biology, University of Vienna, Vienna, Austria. jorg.massen@univie.ac.at.
authors.forename: Jorg J M
authors.initials: JJ
authors.lastname: Massen
mesh_terms: D000818:Animals; D032882:Comprehension; D003299:Cooperative Behavior; D010311:Parrots; D011340:Problem Solving; D012201:Reward
keywords: Affiliation; Cooperation; Kea; Loose-string paradigm; Parrot; Reward division