Name:
Date:
Class Period:
Genetic Drift Activity
In this activity, you will examine the effects of genetic drift on the
phenotypes of a population of the organism Colored pompomius. You may
work with a partner on the activity, but each person must complete their own handout and answer
questions in their own words.
Directions:
1. With a partner, obtain a bag of pompoms. This represents the original population of the Colored pompomius organism.
Genetic Drift in Colored pompomius
Color of
pompom from
genetic drift
population
# of each color
from genetic
drift
population
% of each
color from
genetic drift
population
Blue
Green
Orange
Yellow
Red
Pink
Color of
pompom from
original
population
# of each color
from original
population
% of each
color from
original
population
Blue
Green
Orange
Yellow
Red
Pink
Total # of
pompoms in
genetic drift
population =
Total # of
pompoms in
original
population =
3. Open the bag and WITHOUT LOOKING remove 6 pompoms and place them on your table. This represents the genetic drift
population. Record the numbers and percentages of the different colors of C. pompomius for the genetic drift population.
Calculate percentages using the following formula: (# of colored pompoms/total number of pompoms) x 100. For example, if
your genetic drift population contains 3 green pompoms and a total of 6 pompoms, your equation would be 3/6 x 100 = 50%.
4. Only after you have filled in the table for the genetic drift population, empty the rest of the bag and fill in the table above
with the numbers and percentages of each colored C. pompomius organism for the original population. The 6 pompoms you
removed are included in the original population data.
5. Answer all post activity questions on the back of this page.
Post activity questions:
1. Look at the colors in your genetic drift population and the corresponding percentages. Now, compare those to the same
percentages of each color in the original population (for example, in the genetic drift population, red might have had
percentage of 50% while in the original population red was only 16%). Write your comparisons for each color in a list format
(use bullet points).
2. Does the new genetic drift population accurately represent the original population? Support your answer using your data
from the table on the previous page.
3. What colors in the original population are NOT represented in the genetic drift population?
4. When you compare the percentages of each color, are they the same for the original population and the genetic drift
population? Explain why or why not.
5. Let's assume that the pompoms are praying mantises and that the new environment consists of lots of green plants and
many bright red flowers. Which colors in the genetic drift population would have more fitness in this new
environment? Why/how? How might that affect the alleles for those individuals?
6. Which pompoms would be more fit in the environment described in question 5 and why? What might happen to the alleles
for those individuals that are less fit?
7. Pick a cause for genetic drift (either bottleneck or founder's effect) and write a reason for why the pompom organisms
might have experienced genetic drift. (examples: storm, disease, immigration, new predator, lack of food...). Be sure to
indicate which cause you are describing.