How well Crows process human faces?

Crows learn faces quickly and pass on their knowledge for generations. 

Researchers at the University of Washington wore masks while they trapped, banded and released crows on the school’s campus. The crows were not harmed, but the experience was nonetheless frightening for the birds. From then on, whenever a researcher donned the mask and walked across the campus, the crows raised an alarm. Once, the researcher even wore the mask upside down – and the crows tilted their heads upside down to look at the face, then raised an alarm. When the researchers wore different masks, the crows did not react.

Today, 17 years later, once or twice a year, the researchers continue to wear the mask on campus. Perhaps not surprisingly, the crows react in the same way they did 17 years ago – dive bombing the researcher and making alarm calls. When young crows see the mask wearer for the first time, they observe the behavior of older crows and learn that the masked intruder is bad news.