Data for: Effect of heterospecific and conspecific competition on individual differences in tadpole behavior

Repeated social interactions with conspecifics and/or heterospecifics
during early development may drive the differentiation of behaviour among
individuals. This behavioural differentiation may occur through
individuals behaving more different from each other on average and/or
individuals behaving more consistently. Competition is a major form of
social interaction and its impacts can depend on whether interactions
occur between conspecifics or heterospecifics and the directionality of a
response could be specific to different behavioural traits. To test this,
we reared tungara frog tadpoles (Engystomops pustulosus) either in
isolation, with a conspecific tadpole or with an aggressive heterospecific
tadpole, the whistling frog tadpole, Leptodactylus fuscus. In each
treatment, we measured the body size, activity, exploration and risk
taking in the presence of a predator in focal E. pustulosus tadpoles six
times during development. We used univariate and multivariate hierarchical
mixed effect models to investigate the effect of treatment on mean
behaviour and on among individual variance between and within individuals
across behavioural traits. There was a strong effect of competition on
behaviour, with different population and individual level responses across
social treatments. Within their home tank, individuals were more
consistent in their movements under conspecific competition but
heterospecific competition caused more variance in the average movement
among individuals. Behavioural responses were also trait specific as
conspecific competition caused greater variability in movements among
individuals in a novel environment. The results highlight that the impact
of competition on inter-individual differences in behaviour is dependent
on competitor species identity and is trait specific. Keywords: animal
personality, competition, conspecific, heterospecific, individual
differences, variance partitioning.