ENVIRONMENTAL ETHANOL AT LOW CONCENTRATIONS - LONGEVITY AND DEVELOPMENT IN THE SIBLING SPECIES DROSOPHILA-MELANOGASTER AND DROSOPHILA-SIMULANS

D. simulans adults show an increase in longevity when exposed to 0·5-3·0% atmospheric ethanol in the absence of other food. The offspring produced in atmospheric ethanol also developed best at 0·5-3·0%. D. melanogaster adults show longevity increases, when exposed to 0·5-9·0% ethanol, which always exceed D. simulans; these increases are maximal in the 0·5-3·0% range. Larvae of D. melanogaster developed at all concentrations of ethanol, and at 0·5% to the adult stage. For development times, both species show minima at similar low ethanol concentrations. Therefore both species show maximum fitness at low alcohol concentrations, but only D. melanogaster can utilize high concentrations. This parallels the field situation, since D. simulans coexists with D. melanogaster at low concentrations, while only the latter is found at high concentrations. © 1979, CSIRO. All rights reserved.