CRB - The Impacts of Tropical Forest Fragmentation on Population Structure, Seed and Pollen Gene Flow and Future Genetic Diversity in the Tropical Tree Corythophora alta.

Georgetown University, Washington DC

Investigators

Abstract

9983014 Hamilton Tropical deforestation creates areas cleared of all trees and small, remnant patches of trees. Such forest fragments become refuges and the only source of future populations in a deforested landscape. The goal of this research is to determine if forest fragmentation causes changes in the movement of genes (gene flow) in tropical tree populations that may lead to loss of genetic diversity and increased extinction risk. This study will utilize experimental forest fragments at the Biological Dynamics of Forest Fragments Project near Manaus, Brazil and a canopy tree in the Brazil nut family, Corythophora alta, as a model species. Using nuclear and chloroplast DNA genetic markers to estimate pollen and seed movement, this study seeks to compare genetic organization and gene flow patterns of tree populations in undisturbed forest and fragmented forest. This research will estimate the impact of present-day tropical forest destruction on the genetic base of future forest populations that will inhabit geographically restricted areas. The results will give insights into the future genetic condition of degraded natural habitats, genetic information for biological reserve design and agroforestry projects, and a better understanding of the evolutionary genetics of tropical trees. The ultimate goal of this work is to estimate potential genetic impacts of fragmentation in order to prevent genetic erosion in species-rich Amazonian forests.