Date of this Version
Published in Science, New Series, Vol. 195, No. 4278 (Feb. 11, 1977), pp. 580-582.
Blue jays learned to respond differentially to the presence or absence of Catocala moths in slides. This detection of the moths by the jays was affected by the background upon which the moth was placed and its body orientation, thus providing an objective measure of crypticity. These procedures are useful for the study of visual detection of prey.