Visual perception of light intensity in Drosophila melanogaster wild type and ort1 mutants

Abstract

The objective for this study was to determine whether wild-type and ort¹ mutant Drosophila melanogaster differ in their perception of light intensities. Previous studies have shown that Drosophila exhibit greater movement towards brighter environments than dim places. We predicted that ort¹ mutants, which lack R1-R6 photoreceptors, would not perceive blue light to be as intense or bright as wild type and if there was no difference in their perception of light intensities they were expected to travel the same distance towards blue light. Due to red light colour-blindness in Drosophila, neither wild type nor ort¹ mutants were expected to move towards red light. We illuminated blue and red films on each side of a T-maze and measured the distance traveled by wild-type and mutant flies from the centre of the maze. Although a trend was observed indicating that wild type and mutants moved more towards blue light than red light, we found that wild type and ort¹ mutants did not differ significantly in the distance traveled towards blue light. Thus, we failed to reject our null hypothesis reflecting that there was no difference in the perceptions of light intensity between wild type and ort¹ mutants.