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Date of Award


Document Type


Degree Name

Master of Arts (M.A.)




24 pairs of newly-hatched Leghorn chicks were randomly divided into 3 groups. Ss in one group followed a moving object for 30 min on Day 1 of life; Ss in another group followed for 30 min on Day 2; Ss in the remaining group followed for 15 min on Day 1 and 15 min on Day 2. One S in each pair followed by his own effort, while the other S rode behind the object in a transparent box. On Day 4, Ss were tested for the duration of following of the object. No important differences among groups were observed. On Day 6, Ss were tested for ability to discriminate between the original and a novel object, and for following the original. Active Ss scored significantly higher than passive Ss on all Day 6 tests; Ss trained on Day 2 scored significantly higher on the following than Ss trained on Day 1. The results suggest that the ‘law of effort’ may apply more to discrimination than to recognition of the imprinting object.