Sexual reproduction requires close proximity of mates, but ensures genetic variation in the local population. Although independent of cross-pollination, asexual reproduction can however, reduce genetic variation in the immediate population and ultimately limit out-crossing, gene flow, and the genetic variability of offspring.
Using the dioecious liverwort, Marchantia inflexa (Marchantiaceae), Brzyski et al. quantify how reproductive mode and the genetic structure of populations varied according to habitat size. Asexual reproduction dominated most populations, but male plants were more likely to be aggregated than females and male sgenotypes were more likely to be associated with clones than females in large patches. Variation in the population structure of sexes and genotypes are together essential components of our understanding of population persistence and future adaptability in asexual species.