Cladocera play key roles in aquatic food webs. Understanding the mechanisms that govern
their distribution is therefore invaluable to understand aquatic ecosystem functioning. This is particularly true for the unique tropical cold-water ecosystems on Africa’s highest mountains, which are isolated and show high sensitivity to global change. We will investigate processes shaping the communities and (genetic) diversity of Cladocera in lakes on Mount Kenya, by collecting Cladocera samples and environmental data from >30 lakes, and sediment cores spanning the last 1000 years from four lakes. Assessment of Cladocera diversity and spatial distribution involves morphological characterization and phylogenetic/phylogeographic surveys. Assessment of variation through time will combine multi-proxy paleolimnological techniques with state-of-the-art paleogenetic analysis of dormant eggs, and will provide information on (a) temporal changes in population genetic structure and possible links with documented changes in local factors (competition, predation and abiotic factors) versus spatial configuration (taking into account dispersal pathways), (b) the capacity of populations to resist displacement by invading species/genotypes, and (c) the role of egg banks in reestablishing local populations. Besides providing fundamental insight in drivers of community ecology, this study will also deliver means to assess global-change effects on the ecological integrity of tropical cold-water lakes.