HIGH ETHANOL TOLERANCE IN 2 DISTANTLY RELATED DROSOPHILA SPECIES - PROBABLE CASE OF RECENT CONVERGENT ADAPTATION

1. D. lebanonensis was found to be more abundant in wine cellars of Spain than outdoors. 2. This suggested that the species could have developed a high alcohol tolerance in a similar way to D. melanogaster. 3. Laboratory analysis confirmed this hypothesis and, surprisingly, showed that D. lebanonensis was much more tolerant to alcohol and more able to use it as as food than is D. melanogaster. 4. Environmental alcohol seems to be the selective factor which determined this convergent adaptation. 5. However the difference between the two species could also be explained by assuming that the main target of natural selection was not the same in the two species: ethanol detoxification in D. melanogaster and metabolic utilization in D. lebanonensis. © 1979.