Temperature map of the east coast of the U.S. showing the populations of D. melanogaster that were collected and assayed. Collection sites for the latitudinal & seasonal populations are shown in white stars and black dots respectively. Bowdoin, Maine (ME); Lancaster, Massachusetts (MA); Media, Pennsylvania (PA); Charlottesville, Virginia (VA); Athens, Georgia (GA); Jacksonville, Florida (JFL), Homestead, Florida (HFL).