ADULT LIFE-SPAN IN DROSOPHILA-MELANOGASTER POPULATIONS SELECTED FOR LONG AND SHORT DEVELOPMENTAL PERIOD

The relationship between pre-imaginal developmental period and adult l ife span was studied in Drosophila melanogaster populations not-select ed and selected for long ((x) over bar = 386 h) and short ((x) over ba r = 226 h) developmental period during 433 and 650 generations, respec tively. An opposite and statistically significant life span difference between sexes was observed in the selected populations. In the slow p opulation, females showed a significantly longer life span while the m ales had the shortest longevity. Thus, a slight positive correlation w as observed only in females of the slow population which however had d ecreased fecundity. This may account for their greater longevity. The apparently random results in backcrosses suggest that life span is a c omplex character and many factors such as nuclear and mitochondrial ge nes, sex, and physiological, ethological and environmental traits inte ract for its determination.