Covariation of thermal physiology and personality in the lizard lampropholis delicata (#184)
Consistent individual differences in behaviour, referred to as personality, are a widespread phenomenon in animals. Some personality traits can become correlated to form a syndrome. The underlying mechanisms promoting such correlations remain unresolved. It has recently been proposed that physiology is one such mechanism. Current research focuses primarily on the link between metabolic rate and personality with little emphasis of other physiological traits. Considering the effects of temperature on behaviour in ectotherms, it is likely that variation in thermal physiology at the individual level may reflect variation in personality. Accordingly, we assessed the co-variation between personality and thermal traits in the delicate skink (Lampropholis delicata) by measuring the thermal preferences and optimal performance temperature and a range of personality traits. Data were then used to determine if individual placement on the hot-cold physiological axes corresponded to the placement along the personality axes. We predicted that high thermal traits would be positively correlated with activity, exploration, and boldness where “hot thermal types” would be more active, exploratory, and bolder whilst the opposite would be true of “cold thermal types.” Skinks did indeed exhibit a “thermal type” and these consistent individual differences in physiological traits were correlated with personality types. Our results suggest that variation in behaviour may be promoted, or even constrained by, thermal physiology and highlight the need to integrate thermal traits within the behavioural syndrome concept.