A Review of Cognitive Abilities in Dogs, 1911 Through 2016: More Individual Differences, Please!

In this review, we pose and respond to three questions concerning canine cognition: How has the history of this field influenced what we currently know about dog cognition? How confident should we be about what we know? Finally, what should we find out next? We begin by presenting two perspectives on canine cognition. We then survey the existing literature by conducting a quantitative summary of over 100 years of empirical work, focusing on power and replicability. Last, we lament the dearth of individual-differences studies in dog cognition (only three since 1911). We claim that a test of dog IQ with good psychometric properties will benefit basic science on dog and human health (including aging and dementia research). As a complement to an existing rich program of ethological investigation, we argue that individual-differences work on dogs should be a research priority.