Organisms, including man, play an important role in ecosystem processes. However, little work has examined how man-made environmental changes affect the way organisms evolve and adapt to modified ecosystems. Our aim is to explore the evolutionary mechanisms involved in local adaptation of species to anthropogenic environmental changes. The project will assess how cultural eutrophication (i.e. nutrient enrichment of freshwater systems) influences evolutionary changes in organisms using a multidisciplinary approach involving population genetics, genomics, and palaeo-genetics. The applicant will focus on genes from pathways involved in the handling of phosphorous (P) in natural populations. The model chosen is the waterflea, Daphnia pulex. The applicant expects to find changes in the genotypic composition and physiological mechanisms both over time (between populations resurrected from dormant egg banks at different dated layers in sediment cores) and over space (between extant populations inhabiting lakes that differ in eutrophication history). The main objectives are: 1) Characterize neutral genotypes and those under selection from cores and extant populations within each lake; and 2) Find natural genotypes differentially-adapted to low and high carbon (C):P levels, via genomic (transcriptome) tracking. This multidisciplinary approach represents an original way to tackle problems of great evolutionary, ecological, and economical importance. Particularly, cultural eutrophication is a major ecological concern of increasing importance due to the direct implications for humans. This IOF proposal will involve two high quality institutions, Univ. of Oklahoma (UO) and Spanish Council for Scientific Research (CSIC). Other international collaborations with the UO Biological Station (UOBS), Daphnia Genomics Consortium (DGC), and Center for Genomics and Bioinformatics (CGB) will be established.