Investigation Sequence


Evolution and Equilibrium

Written by:

Lara Morrow and Ben Schmitz                 Date


Focus Questions

What happens when marbles are pulled form the bucket?


Content: Earth, Physical, & Life


Cross cutting concepts

Physical characteristics determine the natural selection of an organism.
Evolution is a series of changes that affect the outcome of an organism.

Science Practice


Personal, Social, Technology, Nature of Science, History


Background information

Objectives: Students will use different colored marbles to decide what marbles to decide what marbles are more likely to survive the process of natural selection.

Vocabulary: Evolution- a series of changes that account for the present form and function of object.

Natural Selection- The characteristics that inhibit reproductive success decrease in frequency from generation to generation.

Materials: Marbles (colored and clear), 5 gallon buckets, H2O, and towels

Activity Sequence


1. Explain the activity of evolution process

A. We are going to break into groups of 3 or 4.

B. Get together and designate someone to come get the materials and one person to record results.

C. Your group will need to get a bucket, marbles, a towel, and ice cream pail.

D. Explain to the students that each person n their group will reach into the bucket three times and take out an organism (marble) one at a time for 10 seconds.  They may only remove the marbles that they can see!

E. After removing the marble they must add a clear marble to the bucket.

F. Have the recorder write the color the marble removed each time.


1. Discuss results within the group.

2. Have the students infer why the clear marbles were not chosen most of the time.

3. Have the students answer the following questions about the experiment.

4. What does the data reveal about evolution and or the process of natural selection?

5. How did the colors affect your selection when you reached into the bucket?

6. Can you think of an example in nature where this occurs?

7. Discuss


1. Ask the students if they can explain the process of natural selection.

2. Explain to the students that throughout millions of years all species have undergone this process. Even humans have evolved and changed under different circumstances. The marble experiment shows how natural selection only leaves some specific few left to reproduce and pass on characteristics. (clear marbles)


Activity Descriptions


Dr. Robert Sweetland's notes