Name _________________________________________
Date ___________________
Genetic Drift Activity
Purpose: To simulate genetic drift and gene flow as mechanisms for the evolution of a population.
Directions:
1. Grab a bag of Plain M&M’s and a paper towel; this represents the original population of the Colored
candius organism.
2. Carefully tear one corner off the bag and WITHOUT LOOKING, remove 6 M&M’s and place them on
the paper towel; this represents the genetic drift population. Record all the necessary information for the
genetic drift population.
3. Only after you have recorded all the info for the genetic drift population, empty the rest of the bag and
record the necessary information for the original population. The 6 M&M's you removed are included
in the original population data.
4. Enjoy your M&M’s as you answer all post lab questions.
Data Table: Genetic Drift in Colored candius
Color of
# of each
% of each
candy in
color
color in the
population
(Genetic
Genetic drift
(Genetic
Drift)
population
Drift)
Blue
3/6
50
Color of
candy in
original
population
# of each
color in
original
population
% of each
color in
original
population
Blue
16
28.07
Green
14
24.56
Orange
8
14.04
Yellow
Yellow
6
10.53
Red
Red
5
10.53
Brown
7
12.18
Total # of candy
in original
population =
57
Green
Orange
Brown
2/6
33
1/6
17
Total # of candy
in the Genetic
drift population
=
6
Post lab questions:
1. How do the original population percentages compare to the genetic drift percentages?
2.
What colors in the original population are NOT represented in the genetic drift population?
3. If M&M’s could reproduce, what would the offspring/generations of the genetic drift population look
like?
4. Which ones would have less fitness? Why/how? What might happen to the alleles for those individuals
that have less fitness?
5. Let's assume that the M&M's are preying mantises and that the new environment consists of lots of
greenery and many bright red flowers. Which colors in the genetic drift population would have better
fitness in this new environment? Why/how? How might that affect the alleles for those individuals?