Friday, June 10, 2011

DYO #2: Fruit Fly Population Investigation

Problem (Question): How does the amount of female and male fruit flies affect how many adults there will be in three weeks?

Hypothesis: If (IV) we put in two females and one male with food in a vial/container, then (DV) I expect to see 323 fruit flies by the end of three weeks because since there is twice the amount of adult females, then there will be more egg production.

Background Research: In class, we read a passage based on fruit flies. I learned that after two days of becoming an adult, a female fruit fly can start laying eggs. Also, that they lay 20 eggs per day. Instead of always having sexual intercourse to make babies, they can store the males sperm. So this helps them produce a large amount of eggs in such little time.

Procedure:
  • Step 1: Chose my combination. (MFF)
  • Step 2: Put food in the vial
  • Step 3: Put flies to sleep with flynap
  • Step 4: Identify which is female and male
  • Step 5: Put fruit flies in vial
  • Step 6: Push stopper in the vial and put it next to your tank
  • Step 7: Make weekly observations of your vial plus 2 other group vials
  • Step 8: Count the # of fruit flies in the vial by putting them to sleep with flynap
  • Step 9: Then feed them to the spider
Data Table and Graph: The Effect of Male and Female Fruit flies on the Number of Adults After 3 Weeks








Analysis: I observed 3 vials, each of them having 2 females and 1 male in them. At the end of 3 weeks, each vial had a different amount of adult fruit flies. Vial AGDE had 112 adults. Vial 24 had 88 adults. Vial KJH had 60 adults.

At the beginning of my experiment, I hypothesized that if I put 2 female and 1 male fruit fly with food in a vial then I expect to see 323 adults in 3 weeks. I thought this because since there was twice the amount of adult female fruit flies then there will be more egg production.

My data did not support my hypothesis because there was 260 fruit flies in total instead of 323. I was 63 fruit flies short.

This could be because maybe we messed something up in our experiment, like possibly miscounting the number of fruit flies. Or some of the larva did not hatch in time like the others, or there just wasn't as much egg production as I thought there would be.

Conclusion: In my experiment, I wanted to find out if there will be an exact number of fruit flies I predicted there to be in 3 weeks. When I got my ending result, I was a bit confused. I assumed that there was probably more males than females born, so that could have led to less production. My data did not support my hypothesis because I expected there to be 323 fruit flies by the end of 3 weeks and I got 260. Apparently, there is no sources of error in out experiment. Maybe we can try this experiment again by putting in one more female, or just hoping that there is more female adults being born. One question I would like to investigate further is if the environment effected the process of the fruit fly process.