Prickly issue

Europe's urban corvids are using anti-bird spikes from nearby buildings to make their nests

- Stuart Blackman

CROWS AND MAGPIES ARE NOTORIOUSLY clever birds. But in the light of new research, one could be forgiven for thinking that their intelligence extends to an ironic sense of humour. Why so? Because Dutch biologists have documented both species building their nests from the spikes deployed on buildings around the world to discourage roosting birds.