FITNESS AND ITS COMPONENTS IN DROSOPHILA-MELANOGASTER

Fitness and its components in Drosophila melanogaster were estimated under the homozygous condition. All of these parmeters, except for egg-to-adult viability and female fecundity, were measured under interspecific competition with D. hydei. The following results were obtained: (1) Significant genetic variation was detected in fitness, productivity, adult viability, total egg-to-adult viability and female fecundity. (2) Significant correlation was obtained between fitness and productivity (r(p) = 0.792 for phenotypic correlation, r(g) = 0.945 for genotypic correlation), between fitness and total egg-to-adult viability (r(p) = 0.355, r(g) = 0.395), and between fitness and female fecundity (r(p) = 0.451, r(g) = 0.511). (3) There was no significant correlation between total egg-to-adult viability and fecundity (r(p) = -0.046). The biological implications of the interrelationship between fitness and its components are discussed.