Data from: Naturally occurring variation in tadpole morphology and performance linked to predator regime

Divergent natural selection drives a considerable amount of the phenotypic
and genetic variation observed in natural populations. For example,
variation in the predator community can generate conflicting selection on
behavioral, life-history, morphological, and performance traits.
Differences in predator regime can subsequently increase phenotypic and
genetic variations in the population and result in the evolution of
reproductive barriers (ecological speciation) or phenotypic plasticity. We
evaluated morphology and swimming performance in field collected Bronze
Frog larvae (Lithobates clamitans) in ponds dominated by predatory fish
and those dominated by invertebrate predators. Based on previous
experimental findings, we hypothesized that tadpoles from fish-dominated
ponds would have small bodies, long tails, and large tail muscles and that
these features would facilitate fast-start speed. We also expected to see
increased tail fin depth (i.e., the tail-lure morphology) in tadpoles from
invertebrate-dominated ponds. Our results support our expectations with
respect to morphology in affecting swimming performance of tadpoles in
fish-dominated ponds. Furthermore, it is likely that divergent natural
selection is playing a role in the diversification on morphology and
locomotor performance in this system.