Behavioural data (cognition and personality)

Mainland and insular lizards’ behavioural traits were assessed using various experimental settings under controlled conditions. Specifically, we measured five personality-related behaviours (aggressiveness, boldness, exploratory behaviour, neophobia, and sociability) and four cognitive traits (spatial and reversal learning, inhibitory control, and problem-solving ability). Aggressiveness was estimated by scoring the lizards’ behaviour (number of biting attempts) in response to their mirrored image. Boldness was assessed in an anti-predatory context and quantified as the latency to emerge from a shelter after a simulated predator attack. Exploratory behaviour was measured by scoring lizards’ behaviour (i.e. time spent moving) in a novel environment. Neophobia was evaluated by observing changes in lizards' feeding latency when a novel object—brightly coloured and artificial—was placed near a familiar food source. Sociability was assessed as attraction towards the odour of conspecifics. Spatial and reversal learning were assessed in a spatial and reversal learning task during which lizards needed to learn and later re-learn the location of a safe hiding spot. Lizards’ ability to exercise inhibitory control was tested with a detour task, during which they had to surmount a transparent barrier to reach the prey. The problem-solving ability of the lizards was judged from their performance in a lid-removal task.