The Effects of Age of Male and Female Parents on the Life Cycle of Drosophila melanogaster

The durations of the egg, larval, and pupal stages remained constant regardless of parental age. As parental age increased, the longevity of adult progeny decreased, more so in female than in male offspring. Reciprocal crosses between young and old flies indicated that the decreased longevity of adults may have been correlated with increased age of the female rather than the male parent. The number of offspring generally decreased as the parental age increased, but a noticeable increase was observed when the female parent was 15 days old.