Exploration and spatial cognition show long-term repeatability but no heritability in the Aegean wall lizard

Abstract

Recently, biologists have become increasingly interested in cognitive variation among individuals and how it relates to differences in fitness. However, very few studies so far have studied the long-term repeatability and heritability of cognitive performance in wild animals. This is nevertheless crucial information to fully understand the potential ecological and evolutionary impact of individual variation in cognitive performance. In 2019, we assessed exploration, problem solving and spatial and reversal learning in 66 Aegean wall lizards, Podarcis erhardii , then released them in seminatural enclosures consisting of either simple or complex habitat. One year later, we recaptured and retested the surviving lizards and their offspring to estimate the long-term repeatability and heritability of these behavioural and cognitive characteristics. We found that exploration and spatial learning were moderately repeatable, but reversal learning only marginally and learning flexibility and problem solving not at all. Reversal learning ability declined over time in lizards kept in simple habitat, but not in those kept in complex habitats – suggesting habitat-dependent cognitive plasticity. To our knowledge, this is the first study demonstrating (long-term) consistency in cognitive traits within a nonavian reptile. The combination of modest repeatability and low heritability does suggest that, within our study species, personality and cognitive variation among individuals and populations is mostly moulded by environmental effects. • We tested repeatability and heritability of exploration and cognition in lizards. • Only exploration and spatial learning were moderately repeatable between years. • Reversal learning was marginally repeatable. • Lizards showed habitat-dependent changes in their reversal learning abilities. • Heritability estimates were low and nonsignificant.