Genetic Diversity Provides a Useful Measure of Environmental Impacts

Environmental insults diminish an ecosystem's ability to maintain productive and adaptable populations of organisms. We have analyzed the DNA profiles of naturally occurring populations of organisms within freshwater and terrestrial sites with varying degrees of exposure to stressors and find that changes in the underlying genetic diversity of these populations are significantly correlated with the extent to which they have been exposed to anthropogenic stressors. Since it is a population's genetic diversity that is largely responsible for its vigor and ability to adapt to subsequent stressors, these results suggest a generally applicable and sensitive means of directly assessing the impact of stressors upon individual species within an ecosystem.