DROSOPHILA DO NOT SKEW OFFSPRING SEX-RATIO AS PREDICTED BY TRIVERS AND WILLARD (DIPTERA, DROSOPHILIDAE)

Based on both previously published literature and results reported her e, it appears that Drosophila melanogaster meet the explicit assumptio ns of the Trivers and Willard offspring sex allocation model. However, contrary to the model's predictions, offspring sex ratio was not sign ificantly affected when we manipulated factors that influence offsprin g quality. We suggest that contrary to implicit predictions of offspri ng sex ratio models, Drosophila may lack the genetic plasticity to rea dily alter sex ratio.