In the lab that was conducted, students were supposed to examine the tendencies of fruit flies, specifically Drosophila’s, to move toward or away from important stimuli that aide in their survival, also known as taxis. Another objective for this lab was to identify the patterns and relationships between environmental factors and a living organism. Students are supposed to use two bottles to allow the flies to choose which side they want to go to, depending on what substances they are attracted to more. Fruit flies are not attracted to fruits; rather they are attracted to the rotting fruit.
In this lab, students are studying the behavior of animals, ethology, and the factors that contribute to the way they behave. Do certain environmental factors behave as a stimulus to animals?
If the fruit flies were given choices on which substance they are most attracted to, they there wouldn’t be any preference to any over the other.
Materials & Procedures:
Material: In this experiment, the we used: tape, 2 water bottles, scissors, 6 different cotton balls, 1 chamber, about 20 fruit flies, water, lime water, banana, vanilla extract, and ammonia. Procedure: Cut the bottom ends off of two water bottles, and tape them together. I labeled each cap with letter “A” and “B.” I then inserted the fruit flies in through one end. For each new substance, we dropped a few drops of it onto the cotton balls. We observed the fruit flies for about 5 minutes, undisturbed, and then counted the flies at each end. We repeated these stepped for each new substance being exposed to the flies.
Table 1. Fruit Fly Choices
|Trail 1 |Trail 2 |Trail 3 |Trail 4 |
Limewater |Water |Ammonia |Limewater |Vanilla |Banana |Limewater |Banana | |13 |1 |0 |3 |7 |13 |5 |20 | |
1. Did the flies demonstrate a chemotaxis in relation to any of the substances you chose? Be specific. Chemotaxis is a movement in response to the presence of a chemical stimulus. The flies demonstrated a chemotaxis to the vanilla, lime water, and banana. For each trail, the flies either went one way or the other in response to the substance they preferred.
2. Which substances had the greatest positive and negative chemotactic response? Through the trailing, it is evident that some of the substances had positive and negative responses. In this lab that was conducted, the vanilla extract and banana had the strongest positive responses, while ammonia and water had the most negative responses. Ammonia killed all of the fruit flies that were inside the choice chambers.
3. Describe some possible reason for their preferences?
Some possible reasons for their preferences are that they mostly are, however, attracted to fruit. Most of them like the smell of the fruit, and in this case the banana because it rots quickly.
4. What other factors might affect whether or not the fruit flies moved from one part of your choice chamber to another?
5. How can you apply this lab to a real world setting? How might fruit fly preference translate to a real life product? This lab can be applied to the real world setting not only shown through fruit flies, but also with humans. The fruit fly preference can translate to a real life product by, for say in a restaurant they wouldn’t stay where the ketchups or what have it, but it would be near the garbage area devouring over the rotting food.
From this experiment, the behaviors of fruit flies were observed and investigated. Through the sampling of different substance in the choice chambers, it was found that the flies found the banana more desirable than the others and moved towards that side more quickly. This proved the hypothesis that was stated was incorrect. Although, we did make an error; in the trail with ammonia, we added a prodigious amount, which therefore led to the mass killing of the fruit flies causing us to use new ones for the other substances.