title: Frequency-dependent selection for rare genotypes promotes genetic diversity of a tropical palm.
abstract: Negative frequency-dependent selection among species is a key driver of community diversity in natural systems, but the degree to which negative frequency-dependent selection shapes patterns of survival and genetic diversity within species is poorly understood. In a 5-year field experiment, we show that seedlings of a tropical palm with rare genotypes had a pronounced survival advantage over seedlings with common genotypes, with effect sizes comparable to that of light availability. This 'rare genotype advantage' led to an increase in population-wide genetic diversity among seedlings compared to null expectations, as predicted by negative frequency-dependent selection, and increased reproductive success in adult trees with rare genotypes. These results suggest that within-species negative frequency-dependent selection of genotypes can shape genetic variation on ecologically relevant timescales in natural systems and may be a key, overlooked source of non-random mortality for tropical plants.
authors.affiliation: Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana.|Foundation for the Conservation of the Tropical Andes, Quito, Ecuador.
authors.forename: Luke
authors.initials: L
authors.lastname: Browne
authors.affiliation: Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana.|Foundation for the Conservation of the Tropical Andes, Quito, Ecuador.
authors.forename: Jordan
authors.initials: J
authors.lastname: Karubian
mesh_terms: D028023:Arecaceae / Q000235:genetics* / Q000502:physiology; D004484:Ecuador; D065928:Forests; D014644:Genetic Variation; D005838:Genotype; D014329:Tropical Climate
keywords: 
  Oenocarpus bataua
  ; Chocó rainforest; demography; genetic diversity; intraspecific variation; rapid evolution; reproductive success; seedling recruitment; tropics