Natural Selection Activity Sheet (this is the teacher version for our lesson, it is
adapted from CHS FOS II class; note: blue portions will not appear on student
versions, they are included here for teacher to guide the students)
Part I
Materials:
Beak Types: scissors, chopsticks, clothespins, plastic spoons, tweezers
Prey Types: popcorn kernels, small dried beans, toothpicks, paper clips, foam peanuts
Procedure:
1. Each member on your team will use a “beak to feed on prey at each feeding
station. All members on your team will have the same type of beak.
2. Each person will act as a “predator”. Using your hands to hold your beak, pick up
as many prey items as you can during the 15-second time limit. Use ONLY your
beak, and pick up only ONE PREY ITEM AT A TIME.
3. After the 15 seconds have elapsed, record the number of prey you caught by your
team.
4. Calculate the average yield (by dividing the number of prey items by the number
of predators)
5. Obtain and record class results for the average yield of each prey and predator for
stations 1-5.
Beak Type:
Prey Type
# Prey You Caught
Total # for Team
Average Yield
(total/ # predators)
Popcorn kernels
Small dried beans
Toothpicks
Paper clips
Foam peanuts
Class Results Stations 1-5:
Scissors
Popcorn
kernels
Small dried
beans
toothpicks
Paper clips
Foam
peanuts
Chopsticks
Clothespins
Spoons
Tweezers
Part II
The environment in which these birds live has suddenly become very rainy. How might
this affect the survival and reproduction of these birds? In this new environment, some
seeds are larger and some plants do not produce the seeds they normally do. Follow the
rules in Part I above. Record the feeding ability of the birds in this changed environment.
Record the class totals.
Beak Type:
Prey Type
Popcorn kernels
Small dried beans
Toothpicks
Paper clips
Foam peanuts (no
longer produced)
# Prey You Caught
Total # for Team
Average Yield
(total/ # predators)
XXXXXXXXXXX
XXXXXXXXXXX
XXXXXXXXXXX
Class Results Stations 1-5:
Popcorn
kernels
Small dried
beans
toothpicks
Paper clips
Foam
peanuts (no
longer
produced)
Scissors
Chopsticks
Clothespins
Spoons
Tweezers
XXXXXXX
XXXXXXX
XXXXXXX
XXXXXXX
XXXXXXX
Part III
There has been a mutation which leads to a selective advantage for birds with one of the
five beak types. How might you modify a beak type so that it is better suited to gather
prey? After the class decides what this modification is, one group will change their beaks
accordingly. Again, follow the procedure to gather data on the feeding ability of the
birds. Record your group results and then the class results as done in previous parts.
Beak Type: OR Beak Type with New modification:
Prey Type
# Prey You Caught
Total # for Team
Average Yield
(total/ # predators)
Popcorn kernels
Small dried beans
Toothpicks
Paper clips
Foam peanuts
Class Results Stations 1-4 + station with Newly Modified Beak:
Scissors
Chopsticks
Clothespins
Spoons
Tweezers
Popcorn
kernels
Small dried
beans
toothpicks
Paper clips
Foam
peanuts
Part IV
Answer the following questions on a separate sheet of paper and then discuss as class:
1.
2.
3.
4.
5.
6.
How did the change in the environment affect the birds?
What types of resources can be limited in an environment? List five examples.
Were particular birds adversely affected by the change in the environment?
Did any group of birds do better in this new wet environment? If so, which ones?
Which birds would likely have more offspring?
How will the mutation which led to a selective advantage for one type of bird
affect their survival as compared to the others?
7. Is the effect on survival and reproduction of these birds an example of natural
selection or artificial selection? How are they different?
8. Does natural selection operate on individuals or populations? Explain.
9. Can an individual evolve? Explain.