Attraction of Drosophila Buzzatii and D. Aldrichi to Species of Yeasts Isolated From their Natural Environment. I. Laboratory Experiments

The attractiveness of yeast species isolated from rotting c1adodes of Opuntia inermis for adults of the cactophilic species D. buzzatii and D. aldrichi was determined by giving the flies a multiple choice of yeast species and counting the numbers on each yeast at regular intervals throughout 1 day in each of five experiments. Consistent effects implying behavioural differences between sexes, between immature and mature flies, and between the two Drosophila species were found. For immature flies of each species, there were significant differences in the numbers of flies attracted to each yeast, but preferences were more marked for females than for males.