NAME:______DATE:______PERIOD:______

The Scientific Method:

What Makes the Siamese Fighting Fish So Angry?

Part 1

The male Siamese Fighting Fish acts very aggressively towards other males of the same species. They do this to claim territory in which to build a nest for fertilized eggs.

The male Siamese Fighting Fish will also act aggressively when it sees its own reflection, because it thinks it has encountered another male Betta. Pet owners and scientists have observed that other items (not alive) also cause the fish to act aggressively.

We will be using the scientific method to conduct a controlled experiment to determine if a male Betta will act aggressively to an uncolored fish shape, a colored fish shape or a colored square.

Materials:

Two Male Betta fish

Scissors

Ruler

Markers

Envelope

4 white fish shapes

3 pieces of colored construction paper

Procedure:

1.  Collect your materials. Cut out the white fish shapes. Leave one white and color the other three shapes in different colors.

2.  Cut the colored construction paper into 2.5 inch X 2 inch shapes.

3.  Study the diagram below.

4.  Quickly remove the partition between the fish. After thirty seconds, replace the partition. Using the terms from the diagram, describe the fish’s reaction.

______

5.  When you show the fish the other items, rate its reaction based on a scale of 0 to 10. Consider the aggressive display you just saw to be a “10.” Consider no reaction to be a “0.”

6.  Agree on a hypothesis with your group:

If I show the Betta a ______, then it will have ______reaction.

Part 2

7.  You are ready to conduct the experiment. Choose only one fish to use in your trials. Be sure you use the same fish every time. That fish is your experimental group.

The other fish is your control group. It will not be used in the trials, so be sure that it can not see the items or the other fish.

8.  Show your experimental fish the cutout by bringing it slowly to the glass. If there is no reaction within 30 seconds, allow the fish to rest and begin again. Record its reaction in the data table. Repeat three times, allowing the fish to rest for one minute in between trials. Each time you show your experimental fish a cutout, also record the reaction of the control fish.

Description of Cutout / Response of Experimental Betta 0-10 / Response of Control Betta 0-10

9.  Analyze your data by comparing it to your hypothesis. Was your hypothesis correct?

10. Write a different hypothesis and conduct a new set of trials. Write the hypothesis and a draw a data table on the back of this sheet.

Part Three

Questions

1.  What do you think the purpose of a hypothesis is? Explain.

2.  What do you think “controlled experiment” means? Explain.

3.  What do you think is the purpose of having a control group and experimental group? Explain.

4.  Compare the control group and the experimental group in this experiment. What is the same about them?

What is different about them?

5.  What are some things that your fish could have reacted aggressively towards (other than the cutouts) giving you false results?

Describe a way to conduct the experiment to reduce the possibility of false results.

6.  Explain what might cause your control fish to act aggressively without being shown the cutouts.

If the above situation occurred, would you be more or less likely to trust your data? Explain.

7. What conclusions can you draw from your data?

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