Blood Parasite Infection Intensity Covaries with Risk-Taking Personality in Male Carpetan Rock Lizards (Iberolacerta cyreni)

Abstract

Identifying evolutionary and developmental mechanisms underlying consistent between-individual differences in behaviour is the main goal in 'animal personality studies'. Here, we explored whether activity and risk-taking varied consistently between individuals and correlated to various - potentially fitness linked - male traits in Carpetan rock lizards (Iberolacerta cyreni). Lizards showed significant consistency within both behaviours, implying the presence of activity and risk-taking personalities. However, there were no correlation between activity and risk-taking, neither on the between- nor on the within-individual levels, implying the absence of a behavioural syndrome. We found a strong link between the intensity of blood parasite (Haemogregarinidae) infection and risk-taking: lizards with higher infection intensity took more risk. While we cannot distinguish cause from causative in the parasite intensity - risk-taking correlation - our results are in line with the asset protection hypothesis predicting that individuals with lower future reproductive value should focus on the current reproductive event and take higher risk.