Geographic structure of insect populations: gene flow, phylogeography, and their uses.

Geographic structure of populations is a fundamental component of ecology and evolution that combines both demographic and genetic processes, such as gene flow and migration, genetic drift, selection, and population extinction. Recent advances in both molecular biology and theory have revolutionized the field and have not only expanded the availability of data but also facilitated the accessibility and interpretation of current data. These new techniques allow analysis of genetic similarity among populations to be coupled with phylogeography and the distribution of genotypes within and among populations relative to the history of those genotypes. The numerous case studies described herein illustrate the growing impact of geographic structure on insect science, as well as the importance of insect model systems for understanding general concepts in ecology and evolution.