Master of Science (MS), Bowling Green State University, 2016, Biological Sciences

In this study we sought to determine if exposure to environments containing harmful levels of copper contamination results in significant differences in the number of surviving male and female Drosophila melanogaster offspring amongst different stocks. Preliminary experiments investigating the copper defensive response with two different crosses of D. melanogaster exposed to differing concentrations of copper sulfate, showed unusual results. The first cross consisted of females carrying the compound-double X [C(1) DX] chromosome, with markers yellow body (y), and forked bristles (f), crossed to males carrying the marker mutation w1118 producing white eyes. The second test cross consisted of C(1) DX, y f females mated to males with the Binscy X chromosome and bar shaped eyes. Both crosses produce high numbers of male offspring compared to female offspring upon exposure to moderate levels of copper sulfate (CuS04). Subsequent experiments with a third stock of C(1) DX, y w f female flies carrying the yellow, forked, and white-eyed X chromosome markers crossed to males with Binscy X chromosomes also displayed a significant difference in offspring viability with, however, a much lower ratio of male to female flies. Hypothesizing that differences in genetic variation on the X chromosomes, including mutant markers, were responsible for these observed differences, we predicted two experimental results. First, significant differences in female offspring viability compared to male offspring viability within a cross will occur when parental generations are exposed to moderate levels of copper sulfate. Second, we predicted that these experiments will show significant differences in the viability of female offspring between different crosses, while males will show less variation in offspring viability, indicating the importance of incorporating gender and genetic lineage into the design of genetics-based studies.

Committee: Ronny Woodruff (Advisor); Juan Bouzat (Committee Member); Scott Rogers (Committee Member) Subjects: Biology; Environmental Science; Genetics