Data from: Evaluating the role of frequency-dependent selection in controlling the expansion of clonal aggregations in the tropical forest's understory: Insights from a decade-long experiment.

Sexual reproduction, despite its associated costs and risks, is prevalent
among many organisms, presumably to generate and maintain genetic
diversity. This diversity is vital for adapting to environmental changes
and combating natural enemies. Paradoxically, several clonal species also
exhibit high genetic diversity. One theory for the maintenance of this
genetic diversity is frequency-dependent selection, which favors rare
genotypes over common ones, limiting the extent and dominance of a single
clone, thereby preserving genetic diversity. Empirical evidence for this
theory under natural conditions is sparse. Twelve years ago, we
established in the forest fourteen genetically diverse plots where all
plants had a unique genotype (rare genotypes) and paired with them clonal
plots where all plants had the same genotype (common genotypes) to test
whether common genotypes have a disadvantage and frequency-dependent
selection is in action. Clones were created from cuttings from Piper
cordulatum, a naturally clonally reproducing understory plant. We aimed to
test if common genotypes are disadvantaged and if frequency-dependent
selection is effective. Over the experiment's first ten years,
herbivory, pathogen attacks, and plant size remained similar across both
genotype categories. Intriguingly, clones exhibited superior survival
during the initial five years. Survival rates equalize for rare and common
genotypes by the decade's end. By year twelve, survival remained
similar for rare and common genotypes. However, modeled survival
projections based on the twelve-year-long trend suggest that common
genotypes might experience increased mortality in the long run, consistent
with the hypothesis of negative frequency-dependent selection. Moreover,
plants in clonal plots exhibited lower fitness in terms of infructescence
production at the plot level by the tenth year. Our findings suggest that
having low genetic diversity in the neighborhood does not increase disease
or herbivory susceptibility or reduce short-term survival. The impact of
negative frequency-dependent selection is not immediate. However, it could
eventually restrict the survival and reproduction of Piper clones in a
tropical forest's understory, curbing the dominance of any single
genotype and potentially enhancing population-wide genetic diversity.