Development of the chick's responses to light and shade cues of depth.

Abstract

When newly-hatched chicks are raised in cages which are lit primarily from above or from below, and are, after 7 weeks, tested under conditions of diffuse lighting, the chicks will peck significantly more frequently at pictures of grain illuminated in accordance with the conditions under which they were reared. In another experiment, where weekly tests were made during the light-controlled rearing period, the development of responses to the light-and-shadow cues was more rapid in the case of the animals whose cage illumination came from above. "These findings indicate that the direction of lighting experienced in early life determines the nature and the rate of development of the chick's responses to light and shade cues of depth." (PsycINFO Database Record (c) 2006 APA, all rights reserved)