Racial divergence in body weight: A study in the four members of newly evolved nasuta-albomicans complex of Drosophila

In the laboratory, we have generated various Cytoraces as the newly evolved products of interracial hybridization between Drosophila nasuta nasuta and Drosophila nasuta albomicans. These races showed divergence from their par ents in many features, including reduced body size and increased fertility. Here we present data on racial divergence in body weight in two of the hyb rid Cytoraces and the two parental races. Analysis reveals that Cytorace 2 has the highest body weight and D. n. nasuta has the lowest body weight. Th e results suggest that body size and body weight may not be correlated beca use Cytorace 2 has higher fitness, maximum weight but reduced body size.