Lateralization of tool use in New Caledonian crows (Corvus moneduloides)

A. A. S. Weir, B. Kenward, J. Chappell, A. Kacelnik

Abstract

We studied laterality of tool use in 10 captive New Caledonian (NC) crows (Corvus moneduloides). All subjects showed near–exclusive individual laterality, but there was no overall bias in either direction (five were left–lateralized and five were right–lateralized). This is consistent with results in non–human primates, which show strong individual lateralization for tool use (but not for other activities), and also with observations of four wild NC crows by Rutledge & Hunt. Jointly, these results contrast with observations that the crows have a population–level bias for manufacturing tools from the left edges of Pandanus sp. leaves, and suggest that the manufacture and use of tools in this species may have different neural underpinnings.