Sexual isolation among isofemale strains within a population ofDrosophila immigrans

Abstract
Eight isofemale strains of the cosmopolitan speciesDrosophila immigrans derived from a single location in Melbourne, Australia, were crossed in all combinations to test for sexual isolation. Statistically significant sexual isolation occurred in 12 of 28 crosses, with one strain showing significant isolation from the other seven. There were significantly unequal male mating propensities (relative rates of mating) in 7 of the 28 crosses.