Natural Selection: Camouflage vs Survivability Outdoor Lab

Name______Date______Period______

In this lab you and your group will examine a gridded-off area for camouflaged “caterpillars”. The point of this exercise is to determine how successful various colors help a creature survive in specific environments. You will pretend to be a flock of hungry birds turned loose on a field of caterpillars.

Any copying will result in a zero for ALL individuals involved. Do your own work and calculations.

  1. Individually collect caterpillars from the “feeding area” we have set up. Only collect them in the time allotted (10 seconds).
  2. When we get back sort your caterpillars by color and count them. Record the totals on Table 1 under number caught.
  3. Once you have the totals for each one that you caught calculate the percentage you caught for each out of your total. The formula is: Number caught ÷ total you caught X 100 = percent caught for that color. Record this in Table 1.
  4. When you have your totals, go to the board and write it down. Once we have the totals we will calculate the percentages caught for the class. The formula for this is: number of color caught ÷ 100 X 100 = percent class caught. Record these totals in Table 1.
  5. Once you have completed these calculations make a bar graph (percentage you caught and percentage the class caught) in the space labeled Chart 1. You should have two bars for each color of caterpillar. The Y-axis is percent caught. Left bars should be percent caught for you and right should be percent caught for class.

Table 1.

Color of Caterpillar / Number caught / Percentage of your total / Number class caught / Percentage class caught
Dark Green
Orange
White
Black
Red
Light Green
Total / 100.00%

Answer the following questions in complete sentences and do your own work.

1. Describe the plants and ground cover in the grid you were in. Be sure to describe the main colors in it.

2. What color was hardest to find and why do you think this was so?

3. What color was easiest to find and why?

4. Based on the data you collected and knowledge of the environment, what color, or colors (not listed on Table 1), would have provided better protection for caterpillars?

5. Besides camouflage, what adaptations would allow for the caterpillars to better survive?