Tool test for food proves crows are no bird brains

CROWS famous for making use of tools have even more impressive bird brains than previously thought, displaying a type of intelligence that may have been crucial to human evolution.

Seven New Caledonian crows showed scientists they could retrieve an unreachable snack with a stick which first had to be obtained using another tool.

This kind of “metatool” use requires high levels of intelligence and reasoning and has only been seen before in humans and great apes.