Effects of light intensity on preferred environment of wild-type and ort1 mutant Drosophila melanogaster

Abstract

Drosophila melanogaster have photoreceptors in their eyes that are responsible for sensing light. Their phototransduction system is similar to that of vertebrates, making them a useful model organism. Our experiment aims to determine the difference in light intensity preference between wild-type and ort¹ mutant D. melanogaster. We used a T-tube and covered each arm with a different material, simulating different light intensity environments. We placed individual replicates in the T-tube and observed the time spent in each light intensity environment. Using the Kruskal-Wallis statistical test, we found that the wild-type D. melanogaster spent significantly more time in the lowest light intensity (38.0 ± 8.8 seconds) compared to bright light intensity (14.5 ± 7.6 seconds) and medium light intensity (7.5 ± 5.6 seconds), with a p value less than 0.0001. The ort¹ mutant D. melanogaster did not spend a significantly different amount of time in any one light intensity environment, as the p value was 0.6737. Therefore, we support our hypothesis that light intensity has an effect on the time spent by wild type in areas of different light intensities while there is no effect on the time spent by ort¹ mutants in areas of different light intensities. Our results suggest that ort¹ mutants are unable to demonstrate a light intensity preference and that the hclA gene is necessary for detecting light and displaying a light preference in D. melanogaster