Abstract
The aim of this study was to demonstrate the development of expertise in pigeons using the serial-order task. Subjects were trained to learn the correct order of three- and four-item lists. Evidence for expertise was defined as improvement in list acquisition as more lists were introduced. The pigeons’ speed of learning a list improved across successive lists on the transitional (AB)ABC phase, but not on the main ABC phase and the three-item component of the transitional (ABC)ABCD phase. When the data were blocked into lists of five to reduce variability, there was evidence of faster list acquisition for both the transitional (AB)ABC and ABC phases. There was no evidence of faster list acquisition on the four-item component of the transitional (ABC)ABCD phase. Overall, although the evidence was not overwhelmingly positive, many aspects of the pigeons’ serial-list acquisition data match that reported by Terrace, Son and Brannon (2003) for monkeys. The data suggest that non-primates are capable of cognitive tasks once thought impossible for their kind, and challenge the widely held assumption that nonhuman primates are superior to other animals in terms of cognitive ability.