ABSTRACT
Determining the number of colonization events and the origins of each is essential for understanding the biology of invasions and for designing strategies for eradication or control of exotic pests. Any analysis of colonization events must be able to distinguish multiple colonizations, if they exist, and determine the origins of each colonization. This chapter argues that both the genetic data and statistical analysis must focus on individual genotypes. Information from different genetic loci and methodologies can be used to answer different questions. The randomly amplified polymorphic DNA method has been very useful in identifying and mapping loci, but has been less useful for population genetics for several reasons. The estimation of a genealogy, or history of genotypes, is perhaps the most obvious advantage of the phylogenetic approach. Genetic distances, or sequence differences, are calculated between each pair of genotypes and the frequency distribution of these differences is then plotted.
