Meeting Abstract
Song may serve as a reliable signal of cognitive abilities in songbirds because the development and expression of these traits require learning and share dependence on brain function. Specifically, developmental stressors could constrain both song learning and aspects of cognition to generate a correlation between these traits. The negative effects of early stress on song learning are well established and recent work also has shown relationships between song and problem solving in several species. Here we test the hypothesis that developmental stress underlies correlations between song and cognition by examining the effects of early nutritional stress on song and problem solving in the zebra finch. Treatment affected growth: finches from experimentally enlarged broods (stressed) were lighter (d 23 mass) than birds from smaller broods (controls). Treatment affected adult song: control males copied tutor songs more accurately than did stressed males, and control males sang songs that were more stereotyped. Additionally, when both male and female subjects were examined, treatment had mixed effects on cognitive performance: controls learned a spatial task more quickly than stressed birds, while stressed birds performed better in a motor task and a test of inhibitory control (a predictive measure of general problem solving ability). Our results are in line with studies showing negative effects of developmental stressors on growth, song development, and spatial cognition. We find mixed effects of this type of stress on adult cognitive performance, however, leaving questions about the mechanisms that might link song and other cognitive abilities.
