Collaborative Research: An Experiment in Evolution: Rapid Life History Evolution in Drosophila Subobscura

Clarkson University, Potsdam NY

Investigators

Abstract

9981555 Gilchrist Three fundamental questions for evolutionary biologists are: 1) How rapidly does evolution occur? 2) Is the pattern of change repeatable? 3) Are most changes historically contingent, or do the deterministic forces of natural selection dominate? The introduction of the European fruit fly, Drosophila subobscura, into North and South America in the late 1970's provides a unique opportunity to address these questions. Many traits, including genetic markers and body size, vary systematically with latitude among the ancestral European populations. Previous studies show that the North American flies have evolved similar latitudinal patterns in less than 20 years. The studies funded by this award will investigate the South American populations and provide further information on the North American and European populations. This is a unique opportunity to observe evolutionary change as it occurs over a broad geographic range. Species introductions are currently reshaping much of Earth's biological diversity. Many studies assess the impact of introduced species on native populations. Evolutionary changes in the introduced species, however, have generally been neglected even though such changes ultimately determine the ecological impact of the invasion. Furthermore, these natural experiments demonstrate the evolutionary and ecological response of populations to novel habitats, which will help predict the impact of climate change on the distribution and abundance of agricultural pests and insect-borne diseases.