What's the Hole Story?
Background
Science is the process of finding answers to questions about the world around us. Not only “scientists “ do science, most people perform science daily. In this activity you will use science to explore a sample of dirt.
Materials
Magnifying glass sand dirt Egg carton
Water cup ruler plastic spoon
Procedure Part I
1. You have been given a container with dirt in it. Without disturbing the container or its contents, make as many observations as possible about the dirt inside the container.
2. You may have noticed an inverted funnel in your sand. What do you think may have caused it?
Why do you think this.
How could you know for sure?
Antlions are the larval form of a type of neuropteran or "net winged" insect. Although antlions are subterraneous, they pupate into flying adults that superficially resemble--but are not closely related to--dragon flies. The name "ant lion" probably comes from the insect's predaceous lifestyle, particularly to ants and other small insects. Antlions lie in ambush waiting for unsuspecting insects to pass by their lair. Some species of antlion dig conical pits, waiting at the bottom for prey to fall in. Should a prospective prey try to escape, the antlion will flick sand at it, to hasten an avalanche, plummeting the escaping insect to it's doom. At the bottom of the concave pit awaits the antlion, ready to grab its prey with immense jaws approximately a third the size of their bodies.
Make a sketch of what you think an antlion looks like based on the information you have thus far. Make sure you include any special adaptations that an antlion might have for sensing and capturing prey, making it's trap, or living underground. Label the body parts in your antlion sketch, and tell what they are used for.
Observations
Carefully sift through the sand until you find your antlion. Gently place your antlion on a white sheet of paper. Use a magnifying glass to look at your antlion. Sketch what your antlion actually looks like. Label any parts that you think you can identify.
Answer the following questions based on your observations of the antlion:
TABLE 1
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Why do you think so? |
How could you tell for sure? |
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Which is the anterior end? |
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Which is the posterior end? |
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Which way does it move? |
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What structure(s) does it use for movement? |
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How (with what) does it catch its prey? |
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How (with what) does it construct its funnel |
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1. Gently hold the antlion by it’s abdomen. How does it respond?
Why do you think it responds that way?
2. Put your antlion back in the cup with the dirt. Time how long it takes to submerge its self in the soil. __________seconds
3. Do you think an antlion would prefer a wet environment or a dry one?
Why do you think so?
How could you know for sure?
Procedure Part II
1. Obtain a section of egg carton from your teacher. Fill both compartments will soil, making sure the soil is level with but not covering the ledge between the two compartments.
2 Wet one compartment thoroughly with water.
3. Hypothesize which type of soil your antlion will prefer:__________________________________
4. Place your antlion on the ledge between the two compartments, making sure it is facing neither compartment.
5. Observe which soil your antlion buries its self in and record it in the following table.
6. Repeat steps 4 and 5 four times, and determine which type of soil your antlion prefers.
TABLE 2
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Trial |
Wet Soil |
Dry Soil |
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1 |
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2 |
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3 |
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4 |
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5 |
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Average |
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Soil Preference = ______________________________
7. Obtain another section of egg carton from your teacher. Fill one compartment with sandy soil and the other with loamy soil. Make sure the soil is level with but not covering the ledge between the two compartments.
8. Hypothesize which type of soil your antlion will prefer:__________________________________
9. Place your antlion on the ledge between the two compartments, making sure it is facing neither compartment.
10. Observe which soil your antlion buries its self in and record it in the following table.
Repeat steps 9 and 10 four times, and determine which type of soil your antlion prefers.
TABLE 3
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Trial |
Wet Soil |
Dry Soil |
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1 |
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2 |
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3 |
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4 |
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5 |
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Average |
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Soil Preference = ______________________________
10. Now that you have investigated some of the soil preferences of antlions, where do you think you might find them on campus? Why do you think so?
11. What are some other antlion preferences that you might be able to investigate?
12. Label the steps of the scientific method, when did you perform each one during this lab?