TY - JOUR T1 - How clonal are bacteria over time? JF - bioRxiv DO - 10.1101/036780 SP - 036780 AU - B. Jesse Shapiro Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/01/15/036780.abstract N2 - Bacteria and archaea reproduce clonally (vertically), but exchange genes by recombination (horizontal transfer). Recombination allows adaptive mutations or genes to spread within (or between) species. Clonality - the balance between vertical and horizontal inheritance - is therefore a key microbial trait, determining how quickly a population can adapt. Here, I consider whether clonality can be considered a stable trait of a given population. In some cases, clonality changes over time: non-clonal (recombining) populations can give rise to clonal expansions. However, an analysis of time-course metagenomic data suggests that a bacterial population’s past clonality is indicative of its future clonality. Thus, a population’s evolutionary potential - whether it is likely to retain genetic diversity or not - can in principle be predicted from its past. ER -