Food availability early in life impacts among and within individual variation in behaviour

Abstract

AbstractThe availability of food during early life has been proposed as a key proximate mechanism for the development of variation in behaviour among and within individuals.Individuals can vary amongst each other in their personality, plasticity and predictability and if an individual’s behaviour is correlated across contexts this can lead to behavioural, plasticity and predictability syndromes.In this study, we used a split brood design to raise African clawed frog tadpoles (Xenopus laevis) on a high or low diet in food availability and measured the distance they swam in a familiar and unfamiliar context eight times during their development.In a familiar context, we found that there was an increase in among individual variance in plasticity and predictability in the high food treatment. This shows that when resources are not restricted, individuals are not constrained in the expression of their behaviour at certain phenotypic levels.In an unfamiliar context, we found a different response, with an increase in individual variance in personality in the low but not the high feed tadpoles. As unfamiliar contexts may be riskier, our results highlight that individuals receiving less food may take greater foraging risks in novel contexts.Across contexts, we found a predictability syndrome in the high but not the low feed tadpoles, highlighting that cross-context behaviours can become decoupled in some developmental conditions but remain intact in others.Together our findings show that early life conditions contribute to among individual variation in behaviour but that these may only impact the phenotype at specific phenotypic levels and are context specific.We emphasise that having a fundamental understanding of how early development may promote or constrain individual variation can provide a greater understanding of how individuals and populations may respond to novel conditions brought about by anthropogenic activity.