Larval responses to environmental ethanol in Drosophila melanogaster: variation within and among populations.

There is a latitudinal cline in attraction to ethanol of newly hatched D. melanogaster larvae; attraction decreases as one moves from the temperature regions to the Australian tropics. Tropical populations manifest high levels of heterogeneity compared with temperate regions, making tropical populations less dependent on ethanol. Since ethanol is a resource for D. melanogaster, an approach to the genetics of resource utilization in natural populations via behavior genetics of larval ethanol responses is feasible, using isofemale strains as experimental material.