Ecological variation has long been known to drive phenotypic evolution and local adaptation, but does such microevolutionary change in turn affect ecological dynamics? In collaboration with the Jeyasingh lab at OSU, we are working on conceptual and emprical approaches to mechanistically integrate ecological and evolutionary analysis. In particular, we are using an elemental framework to study whether local adpatation leads to evolutionary changes in body stoichiometry, and how differential nutrient sequestration and excretion ultimately affects ecological dynamics. We make use of multiple population pairs of fish inhabiting sulfidic and non-sulfidic environments with the aim to document replicated eco-evo-eco loops in the natural environment.