GEOGRAPHIC VARIATIONS OF LIFE-HISTORY STRATEGIES IN DROSOPHILA-MELANOGASTER .2. ANALYSIS OF LABORATORY-ADAPTED POPULATIONS

Life history traits-hatchability, longevity, and egg production-of fiv e wild-caught populations of Drosophila melanogaster were measured aft er these populations had been reared in constant laboratory conditions during a 4-year period. The results were analyzed together with those that had been obtained with the same populations just after capture. They are probably the first convincing results that reveal the existen ce of genetic variability for some life history traits measured in the laboratory. Besides, no significant phenotypic correlations, either p ositive or negative, between early and late components of fitness were found. Finally, the five populations showed different patterns of gen etic correlation between early and late fitness traits, One of the pop ulations showed a negative correlation, another showed a positive corr elation, while the remaining three populations showed no correlation a t all, This was equally observed at the within- and between-population levels. That result suggests that both the antagonistic pleiotropy hy pothesis proposed by Williams and the concordant pleiotropy hypothesis suggested by Lints are not of general validity.