Putting the best foot forward: Limb lateralization in the Goffin's cockatoo (Cacatua goffiniana).

Abstract

Many parrot species exhibit a high degree of limb lateralization on both the individual and species levels. In particular, the members of the cockatoo family are left-footed for food-holding at proportions reminiscent of right-handedness in humans. Here, we examine the limb lateralization of the Goffin's cockatoo (Cacatua goffiniana), a tool-using and technically proficient species used as a model of parrot cognition. First, we investigated the postural origins theory, originally proposed in primates to explain handedness. According to this theory, the hand that was used by ancestral primates to cling to trees developed finer motor control. Using a series of problem-solving tasks, we tested the possibility that the parrot's postural foot, which is similarly used to grasp tree branches, could be more motorically skilled. Although we did not find support for this idea, we did discover that task type does affect foot use, as subjects switched from using their food-holding dominant foot to their other foot during reaching tasks. We also found that the cockatoos more flexibly switched and used both feet when faced with more challenging tasks. Secondly, we attempted a partial replication of a previous study with parrots derived from the enhanced cognition hypothesis, which claimed that more lateralized individuals were better problem solvers. However, we did not find this relationship to be significant in any of our tasks. We did confirm that individual Goffin's cockatoos are extremely limb lateralized for food-holding in addition to other tasks, which may play a role in their approaches to problem-solving. (PsycInfo Database Record (c) 2024 APA, all rights reserved).