New Caledonian Crows Use Mental Representations to Solve Metatool Problems (Current Biology)

Gruber et al. presented metatool problems to New Caledonian crows, where each stage of the problem was out of sight of the others. Crows had to mentally represent the location and identities of tools and apparatuses to solve the problems correctly. These results show that New Caledonian crows can preplan several behaviors ahead while using tools.