Longitudinal evidence for the emergence of multiple intelligences in assistance dog puppies

Cognitive battery testing suggests that adult domestic dogs, Canis familiaris , have different types of cognitive abilities that vary independently. In the current study, we examined whether these cognitive skills develop and emerge independently in puppies by testing them over a crucial period of development. Service dog puppies ( N = 113) were raised using two different socialization strategies and were either tested longitudinally ( N = 91) or at a single time point ( N = 22). Subjects tested longitudinally participated in the battery every 2 weeks, from approximately 8–20 weeks of age, during and just beyond their final period of rapid brain growth. Control puppies only participated in the test battery once, which allowed us to evaluate the impact of repeated testing. In support of the multiple intelligences hypothesis (MIH), cognitive skills emerged at different points across development, not simultaneously. Maturational patterns also varied between cognitive skills, with puppies showing adult-like performance on some tasks only weeks after a skill emerged, while never achieving adult performance in others. Differences in rearing strategy did not lead to differences in developmental patterns while, in some cases, repeated testing did. Overall, our findings provide strong support for the MIH by demonstrating differentiated development across the cognitive abilities tested.