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Eleven young kakarikis (Cyanoramphus auriceps) were tested on 15 object-permanence tasks in a standardized scale that has been used to assess the development of human infants, some nonhuman primates, and other mammals. The birds successfully completed all tasks in this scale, and many aspects of their testing were similar to human results, such as evidencing the A-not-B error. However, the birds differed slightly but significantly from human subjects in that some of the "invisible displacements" of the later tasks were performed before the earlier visible displacement tasks. These results may relate to common ecological activities of this species. Six of the birds were parent-raised; 5 were hand-raised. The hand-raised birds achieved criteria more qUickly than did the parent-raised birds possibly because the former were more accustomed to the investigator and less distractible in the test situation.

Despite the long divergent evolutionary history of birds and mammals, early avian and primate cognitive development have many convergent features. Some of these features were investigated with a series of tasks designed to assess human infant development. The tasks were presented to young parakeets to assess their means-end problem solving abilities. Examples of these early skills are: attaining and playing with objects, retrieving rewards through use of a stick or rake, or by pulling in rewards on supports or on the ends of strings. Twelve such tasks were presented to 11 young yellow-crowned parakeets ( Cyanoramphus auriceps) to investigate their natural abilities; there was no attempt to train them to do those tasks that they did not spontaneously perform. Six of the birds were parent-raised and five were hand-raised. The birds completed 9 of the 12 tasks, demonstrating all the Piagetian sensorimotor circular reactions, but they failed to hand-watch ("claw-watch"), to stack objects, or to fill a container. Their ordinality on the tasks differed from that of human infants in that locomotion to obtain objects occurred earlier in the avian sequence of development and the mid-level tasks were performed by the two groups of avian subjects in a mixed order perhaps indicating that these abilities may not emerge in any particular order for these birds as they supposedly do for human infants. The hand-raised group needed fewer sessions to complete these means-end tasks.

We report on stable individual differences in young yellow-crowned parakeets across 38 tasks of cognitive development on three scales involving object permanence, means-end relations, and spatial relations. Stable performance ranks on blocks of tasks emerged after 13 weeks in two groups of sibling parakeets, one hand-reared and the other parent-reared. Examination of subject characteristics, such as hatch order, sex, general activity level, avoidances, latencies, social status, and errors, showed no significant correlations with these performance ranks. Characteristic individual approaches to unstructured play activities (from a fourth scale) were consistent with individual behavioral differences seen on the structured cognitive tasks.

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