Crows can remember and differentiate human faces

"I know I know you"
 - The Crow (1994)

(New Scientist, Sept, 10, 2012) - You can run from a crow that you've wronged, but you can't hide. Wild crows remember human faces in the same way that mammals do.

Crows can distinguish human faces and remember how different people treated them, says John Marzluff of the University of Washington in Seattle.

To work out how the crows process this information, Marzluff had members of his team wear a latex mask as they captured 12 wild American crows (Corvus brachyrhynchos). The crows learned to associate the captor's mask with this traumatic experience. While in captivity, the crows were fed and looked after by people wearing a different mask.

After four weeks, the researchers imaged the birds' brains while they were looking at either the captor or feeder mask. The brain patterns looked similar to those seen in mammals: the feeder sparked activity in areas involved in motivation and reward, whereas the captor stimulated regions associated with fear.

The result makes sense, says Kevin McGowan of Cornell Lab of Ornithology in Ithaca, New York. Crows don't mind if humans are in their habitat – but they need to keep a close eye on what we do.

Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1206109109