The proposed research is designed to determine whether genetic correlations between morphology and behavior reflect the sorces of selection in natural populations. Several populations of the Northwest Garter Snake, Thamnophis ordinoides, will be examined for genetic correlations between color pattern and antipredator behavior. Field studies of selection will then be conducted using mark-recapture and field enclosure techniques to determine whether particular combinations of color pattern and behavior have relative survival advantages. The existence of genetic correlations between morphology and behavior means that the traits in question undergo non- independent evolution. An empirical demonstration of selection for a combination of traits will emphasize the need for multivariate approaches to selection. If genetic correlations between morphology and behavior reflect such selection, it will represent the first empirical evidence that selection acts to maintain genetic correlations in natural populations.