AbstractVisual cliff behavior was studied in 120 chicks as a function of 22, 46, 70, 94, or 118 hr of rearing in a deep or shallow environment. Preference for the deep side of the visual cliff increased directly with duration of depth‐rearing but was uninfluenced at any duration of shallow‐rearing. Although qualitative differences existed in the behaviors of those shallow‐ and deep‐reared chicks which crossed the cliff, the loss of depth avoidance by the latter group appeared to be specific to the rearing and testing ap