Genes to ecosystems: exploring the frontiers of ecology with one of the smallest biological units

Genes and their expression levels in individual species can structure whole communities and affect ecosystem processes. Although much has been written about community and ecosystem phenotypes with a few model systems such as poplars and goldenrod, here we explore the potential application of a community genetics approach with systems involving invasive species, climate change, and pollution. We argue that a genes-to-ecosystem approach can reveal patterns and processes that otherwise might remain undetected. To further facilitate the genes-to-ecosystem concept we propose four criteria that allow for the conclusion of a causal relationship between the gene and its effect on the ecosystem. Although most current studies do not completely satisfy these criteria, several come close, and in doing so, they begin to provide a genetic-based understanding of communities and ecosystems, as well as providing sound conservation and management practices.