Drosophila Sitter Lab Report

Whether it is through bioluminescence or natural sunlight, living organisms need light in order to survive. However, not all organisms prefer a high intensity of light, but with light comes access to food and if it happens to be absent, then survival rates are jeopardized.

In this experiment, we investigate the effects of light on Drosophila melanogaster, which have been extensively studied as a model organism for human genetic diseases. Light has been shown to support all life forms by providing a living organism with energy and food. Therefore, the fitness of the two Drosophila melanogaster phenotypes (sitters and rovers) under two different settings (one with light and one without light) was tested. We hypothesized that the availability of light will affect the survival rate of the Drosophila melanogaster for percent pupation.

Materials/Methods:

We set up 2 treatment groups, Light and Dark, within this experiment. Each treatment group consisted of the 20 Drosophila melanogaster larvae (10 rovers and 10 sitters), initially placed in the center. Each group

As suggested by our statistical results, the availability and exposure to light did not significantly alter the survival rates (see Figure 1 and Figure 2). With this in mind, one possible factor that could have affected our results would be cannibalism. Initially, 10 rovers and 10 sitters were placed at the center of the dish and after the duration of one week about 52% of the 20 total drosophila survived. Likewise, because the rovers are faster than the sitters, it may have been possible that they required more food, thus eating the sitters as more rovers survived (in both treatment groups). Our comparison of the survival rate and pupation rate is consistent with this rationale as light did not significantly affect survival nor pupation rates (see Figure 1 and