Recombination in Bacterial Populations

The generation of molecular data for large population samples of bacteria has revealed an unprecedented degree of genomic diversity. This variation is generated and maintained by virtue of very large population sizes, short generation times, and the ability to recombine; that is, to acquire DNA horizontally from other bacteria or from the environment. Superficially, the process of recombination is analogous to eukaryotic sex, as it results in the fusion of genetic material from two distinct partners. This article explores this comparison, and emphasises how the rates, mechanisms, and evolutionary consequences of recombination vary markedly across all phylogenetic scales.