The Molecular Basis of Adaptation in Drosophila

Abstract

In the field of population genetics, genetic variation is of primary importance because it serves as the basis for evolutionary adaptation. Adaptation, another primary concern in population genetics, and one where Bruce Wallace has made numerous scientific contributions, refers to the integration of the phenotype into its environment (Hartl and Clark, 1989). With the advent of the techniques of molecular genetics, we are now able to look at genetic variation at the DNA level. Although this higher resolution provides a wealth of information and, in some cases, can shed light on previously intractable questions, it is certainly one step more removed from the phenotype. It also can quickly become overwhelming: regulatory variation versus variation in structural genes, and the complexity of mapping genotypes into phenotypes especially for quantitative traits, all in order to get at the genetic basis of an adaptation, seems impossibly intricate. The question then is, how can we best make progress in this scientific arena? One reasonable solution is to very carefully select an amiable system in which to work. Such a system should involve an organism that is genetically tractable and genes whose function in a natural environment can be investigated.