Wooly Worm Lab

Wooly Worm Lab Name: ______Evolution Through Natural Selection Date: ______Pd: ______Standard: SB5d EQ: How does natural selection lead to a change in a species?

During this lab you will represent a predacious bird that feeds on “Wooly Worms!” The wooly worms are pieces of colored yarn that have been randomly distributed over a grassy area on the school grounds. Some of the wool pieces will blend into the habitat while others will be easy to find. The colored yarn that you “eat” will be counted, recorded, and analyzed.

Procedures:

1. During a 2 minute feeding period, collect as many of the wooly worms as possible in the collection area.

2. Return to the lab and count the number of each color of worm you “ate.” Record the numbers in the data table below.

3. Record your numbers on the data chart on the board. Record the “Number of Wooly Worms Eaten by Class” in your data chart when the totals are put on the board.

4. Add the number of worms in each column and record the total out of 400 at the bottom.

5. Return all of your wooly worms back to the teacher.

6. Answer the analysis questions on the back of this lab sheet.

Color Number of Wooly Number of Wooly Worms Eaten by You Worms Eaten by Class

1. White

2. Pink

3. Blue

4. Yellow

5. Green

Totals: ____ / 400 ____ / 400 Analysis Questions:

1. What is the main variation in our population of wooly worms at LHS?

2. What type of competition was present in our population of birds at LHS?

3. Natural selection is the process by which individuals that have inherited beneficial adaptations (colors in this case) produce more offspring on average than do other individuals. Do you think natural selection was occurring with the wooly worms? ______

Explain:

4. Which adaptations (colors) were beneficial for the worms?

Which adaptations (colors) were not beneficial for the worms?

5. How would the wooly worm population change over the next few years should this selection continue by the birds at LHS? (Which color worms would increase in number?)

6. Explain what may happen to the wooly worm population in the Spring?

7. Some animals are brightly colored and contrast sharply with their surroundings. What purpose might this coloration serve and how are these species able to survive based on the evidence gathered in this lab?