Patterns and Processes of Biodiversity in Pristine and Fragmented Rainforests of the Ecuadorian Choco

A unifying goal of ecology and evolutionary biology is to describe and understand processes that influence patterns of diversity of life on Earth. Biodiversity is critical for the health, function, and continued viability of this planet, and this dissertation seeks to improve our understanding of the processes drive patterns of genetic diversity and how anthropogenic forces can impact this type of diversity. In this dissertation, I show through a planting experiment and tracking the survival of naturally recruiting seeds that negative frequency-dependent selection of genotypes of the tropical palm Oenocarpus bataua in northwest Ecuador is associated with increased survival and increased population-level genetic diversity. I also show, through a simulation model, that negative frequency-dependent selection of both species and genotypes can drive parallel increases in patterns of species and genetic diversity, though this effect varies on a species-by-species basis. Finally, I show in a deforested landscape in northwest Ecuador that pollen dispersal is especially important for maintaining current levels of genetic diversity of isolated populations of O. bataua, compared to seed dispersal, which tends to limit overall levels of genetic diversity. Together, these studies provide new perspectives on factors driving patterns of both species and genetic diversity in tropical landscapes, as well as providing much-needed data from a threatened tropical biodiversity hotspot.