Isozyme variability in species of the genus Drosophila. VIII. The alcohol dehydrogenase polymorphism in north carolina populations of D. melanogaster

Adult Drosophila melanogaster flies collected from populations broadly dispersed over ecological and geographic strata of North Carolina, and over a period of 4 years, were analyzed for alcohol dehydrogenase phenotypes by gel electrophoresis. Gene frequencies in spring-summer-fall field collections were remarkably stable over all strata. Two winter collections exhibited contrasting gene frequency changes. In one case the results are interpreted in terms of long-distance migration from Florida, while the other is explicable by assignment of a causal role to environmental factors which accompany the winter season.This investigation was supported in part by NIH Research Grant No. GM11546 from the National Institute of General Medical Sciences and by Contract No. AT-(40-1)-3980 from the United States Atomic Energy Commission.Paper No. 4719 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, North Carolina 27609.