ABSTRACT - Routman - DEB-9509118 One of the most important goals of population genetics is to be able to understand the underlying causes of the distribution of genetic variation within and among populations. Scientists usually attempt to understand these causal phenomena by measuring the number of different forms of a gene and their frequencies in each population. Unfortunately, many of the causal mechanisms result in similar geographic patterns, and cannot be distinguished when the data consist only of frequencies. Dr. Routman will attempt to test a new method that incorporates the genealogical relationships of the genetic variants to differentiate among possible underlying causes. Genetic variation in mitochondrial DNA will be measured in populations of Ambystoma tigrinum from the midwestern USA. Genealogies of these variants will be reconstructed, and used in the new method that relates the underlying causes listed above to the geographical distributions of nested sets of related variants. The addition of the genealogical information results in different predictions from the underlying causes. Because some of these causes are actually known in this species, Dr. Routman can test to see if the predictions of the new method are correct. Computer simulations will also be used to test the predictions. If the method withstands rigorous testing, it will be extremely useful for wildlife managers and taxonomists working with a wide variety of organisms.
