Impacts of Natural Selection on Evolution of Core and Symbiotically Specialized () Genes in the Polytypic Species .

Nodule bacteria (rhizobia) represent a suitable model to address a range of fundamental genetic problems, including the impacts of natural selection on the evolution of symbiotic microorganisms. Rhizobia possess multipartite genomes in which symbiotically specialized () genes differ from core genes in their natural histories. Diversification of genes is responsible for rhizobia microevolution, which depends on host-induced natural selection.