Rooks have a remarkable aptitude for using tools, scientists have found.
Tests on captive birds revealed that they could craft and employ tools to solve a number of different problems.
The findings, published in the Proceedings of the National Academy of Sciences, came as a surprise as rooks do not use tools in the wild.
Here, the rook choose the appropriate stones to release a tasty snack from a trapdoor.
Video courtesy of Christopher Bird, University of Cambridge