Is That a Grimace? Ask a Pigeon
PIGEONS have been taught to recognize human facial expressions, upsetting long-held notions that only humans had evolved the sophisticated nervous systems to perform such a feat.
In experiments at the University of Iowa eight trained pigeons were shown photographs of different people displaying emotions of happiness, anger, surprise and disgust. The birds learned to distinguish between these expressions.
Their achievement does not suggest that the pigeons have any idea what the human expressions mean, researchers report. But after a pigeon has learned to distinguish expressions on faces with which it is familiar, it can then correctly identify the same expressions on unfamiliar faces.
The experiments were carried out by Edward A. Wasserman, professor of psychology, and his colleagues. The results are described in a paper prepared for publication.