A few years ago scientists learned that American crows can recognize and remember human faces, particularly faces they associate with bad experiences. Now, new research published in the Proceedings of the Royal Society B shows that the birds can share that knowledge of dangerous humans with other crows.
Five years ago, zoologist John Marzluff and his research team at the University of Washington trapped, banded, and released 7–15 American crows at five different sites near Seattle. Before trapping the birds, the researchers donned different rubber masks specific to each site (a caveman face, for example). While the birds were caged, nearby crows circled the site and sounded alarm calls.
The team then tested the crows’ reactions to the masks. Over the first two weeks, about 26 percent of the crows that the researchers encountered scolded — with a harsh, repeated kaw, accompanied by wing and tail flicking — the masked ...
