Impacts of caudal autotomy on personality

Abstract

Caudal autotomy, the voluntary shedding of a tail, is a last-ditch strategy used by many lizard species to escape from predators. There are several costs associated with caudal autotomy that may cause lizards to change their behaviour during tail regeneration. These behavioural changes may be dependent upon individual differences in response to autotomy (e.g. trait or state-dependent differences) and/or the degree of tail loss, as many lizards have the capacity to only partially shed their tail which probably entails fewer costs relative to complete autotomy. However, no study, to our knowledge, has considered how caudal autotomy, or the extent of autotomy, affects individual behavioural variation. Accordingly, we investigated the effects of both partial and complete tail loss on individual behavioural variation in delicate skinks, Lampropholis delicata. We found that lizards that experienced complete tail loss, on average, became less active and explorative and had much slower sprint speeds following autotomy. These lizards also became more predictable and consistent in their behaviour, exhibiting a notable decrease in their within-individual behavioural variance. In contrast, we did not see any significant behavioural effects in lizards that experienced partial tail loss. We also found a positive among-individual correlation between activity/exploration and neophilia, but tail loss had no effect on the structure of this syndrome. Our results suggest that complete tail loss may impose effects on traits more closely associated with locomotion and predator escape ability, while also constraining an individual's capacity for differential behavioural expression.