Sickness-induced learning in chicks

Abstract

Three experiments showed that domestic chicks reduce the relative intake of a colored solution that has been paired with sickness induced by lithium chloride. Learning occurred after only a single pairing and with a delay of up to 1 hr between the two events. The degree of initial reduction following conditioning depended on the poison dosage. These findings support the general notion that as a result of evolutionary processes the cues used in food selection are easily associated with sickness.