Resurrecting the metabolome: Rapid evolution magnifies the metabolomic
plasticity to predation in a natural Daphnia population
Abstract
Populations rely on phenotypic plasticity and rapid evolutionary
responses to adapt to novel environmental conditions. Because of the
lack of compelling evidence from natural populations, controversy
remains about the interplay between ancestral plasticity and rapid
evolution in driving responses to new stressors. We studied this at the
level of metabolome in a resurrected natural population of the water
flea Daphnia magna that underwent an increase followed by a reduction in
predation pressure within ~16 years. Both the
constitutive and plastic components of the metabolic profiles showed
rapid adaptive evolution. Ancestral plasticity and evolution contributed
nearly equally to the total changes of the metabolomes during both
transitions. The metabolites with higher ancestral plasticity showed
stronger evolution of plasticity when the predation pressure increased,
while this pattern reversed when the predation pressure relaxed. Our
results therefore highlight adaptive evolution in response to a new
selection pressure in this natural population magnified the metabolomic
plasticity to this stressor.