Autopolyploid establishment depends on life history strategy and the mating outcomes of clonal architecture

Abstract

ABSTRACTPolyploidy is a significant component in the evolution of many taxa, particularly plant groups. However, the mechanisms promoting or preventing initial polyploid establishment in natural populations are often unclear. We develop spatially explicit agent-based simulation models to explore how perennial life history and clonal propagation influence the early stages of polyploid establishment. Our models show that polyploid establishment is unlikely among short-lived plants. Polyploids have increased establishment probability when both diploid and polyploid lifespans are long, especially when unreduced gamete production is non-zero. Further, polyploids that combine sexual and clonal reproduction can establish across a wide range of life history strategies. Polyploid genets containing many, far spreading ramets are most successful, but genets with tightly clumped ramets have similar establishment probability when pollen dispersal is local and rates of self-fertilization are high. Clonal architecture has a substantial impact on the spatial structure of the mixed cytotype population during establishment; altering patterns of mating within or between cytotypes, the mechanisms through which polyploid establishment proceeds, and the final composition of the polyploid population after successful establishment. Overall, our findings provide insight into the complex relationship between polyploidy, perenniality, and clonal reproduction, and offer testable predictions for future empirical work.