A fundamental link between genomes and ecosystems is represented by the availability of resources: genes and proteins are macromolecules constituted of atoms that are incorporated into the organisms via bio-geochemical cycles operating at the ecosystem level. Therefore, the availability of the different atomic building blocks of nucleotides and amino acids may in principle represent one of the forces shaping molecular evolution in natural ecosystems. Indeed, recent evidence suggests a pivotal, yet under-explored role of the availability of nitrogen and phosphorus, that are typically limiting in natural ecosystems and are fundamental components of nucleotides and amino acids.
In this framework, our group focuses on a question of central importance in the integration of the evolutionary and ecosystem perspectives: the cost of resource acquisition from the environment and the consequences of such environmental limitations on the molecular architecture of the organisms. We integrate concepts and methods from molecular evolution and ecology to measure the strength of selection induced by nutrient constraints, and to determine the time scale on which this ecological factor is evolutionarily relevant.