Pre Setup
The main subject of this lab revolved around observing the circadian cycle present in fruit flies. The so-called “cycle”, or better known as the “circadian rhythm”, is a biological phenomenon where living organisms are governed by an internal, physiological clock that runs 24-hours, allowing the creature to wake up and fall asleep at regular intervals. The process itself is usually endogenously generated (internally generated), but can be influenced by external cues such as sunlight or temperature.
Setup
To prep for the lab, we first had to separate the male fruit flies from the females, in order to remove the possible situation of the female flies reproducing during the testing stage. Then, we created two sets of flies, one set composed of regular Drosophila flies, and other made up of Drosophila flies with a genetic mutation. We utilized C02 in order to incapacitate the insects and move them into vials. In the end, we had 8 vials of normal functioning files, and 8 vials of mutated flies. The samples were placed in the dark, and monitored every hour. This way, we would be able to make the distinction that the flies were indeed able to follow an internal clock without the use of external cues such as lighting. Our expectation is that the presence of a circadian rhythm will be observed in the normal Drosophila flies, and not in the mutated sample set.
Results
Here are a few snippets of the results from the lab. As you can see from the data, it seems that the regular Drosophila flies do indeed follow some sort of circadian rhythm, as they look to be active for around 5-6 hours (the specific hours of the day vary a bit between the flies), and inactivate for the remaining portion of the 24 hours. In contrast, the mutated flies exhibit little to no circadian patterns, fluctuating between being awake and asleep at seemingly random hours of the day. The rest of the flies that display no movement at all are most likely dead.
Reflection
I thought this experience was especially interesting because I have never worked with live organisms under a microscope before. Analyzing the sleep patterns of the flies and discovering the presence of a circadian rhythm was a bit eye opening in that I was reminded that even living organisms may possess some ‘robotic qualities’ similar to machines. In a way, this lab pushed me to seek out other behaviors that animals may possess that are seemingly ‘machinelike’ to incorporate into my final project.