Results of Experiments 1 and 2.

The proportion of trials (of 20) upon which chicks showed a preference to approach and peck the target stimulus in the generalization phase, as a function of training on aligned (BAL) or misaligned (IMBAL) training stimuli. The number of occasions upon which chicks showed a category preference consistent with their training was significantly different between the IMBAL- and BAL-chicks in both Experiments 1 and 2.