Creative Movements: What Causes the Wavelike Movement in an Earthworm’s Body?
What causes the wavelike movement in an earthworm's body?
- Smooth tabletop
- Lay the Slinky on a table.
- Hold the ends of the Slinky with your hands.
- Hold your left hand still while your right hand pulls the other end of the Slinky out about 6 inches (15 cm).
- Release the end of the Slinky held by your left hand.
- Observe the movement of the Slinky.
The Slinky stretches and then springs back together. It moves forward about 6 inches (15 cm) from its old position.
The Slinky, like an earthworm, moves by stretching out long and thin. Waves of motion are observed as the Slinky springs forward. The earthworm also moves by a series of wavelike movements that pass from one end of the worm's body as it pulls up short. The wavelike motion that ripples through an earthworm's body is called peristalsis.
Would the surface the Slinky is placed on affect its movement? Repeat the experiment, placing the Slinky on different surfaces such as a carpet, grass, or a sandy surface.
Note: Obtain permission from your teacher to use live animals as part of your science project.
- What keeps an earthworm from slipping backwards? Gently rub your finger over the bottom side of an earthworm. You should be able to feel the bristles. Place the earthworm on a moist paper towel, and gently pull the worm forward with your fingers. Be very gentle, or the end of the worm will break off. Photographs of this process can be used with the results as part of a project display. Return the earthworm to its natural environment after the experiment.
- Demonstrate how the amount of air in a fish's swim bladder causes the fish to move up and down in water. Fill a plastic soft-drink bottle with water until it overflows. Partially fill a glass eyedropper with water and drop the eyedropper into the bottle of water. If the eyedropper sinks, remove it, squeeze some of the water out and put it back in the bottle of water. Put the cap on the bottle, and squeeze the sides of the bottle with your hands. Release the bottle. The moving of the water in and out of the dropper changes the volume of air inside the eyedropper and thus causes the dropper to rise and fall in the water. Attach a cardboard cutout of a fish to the eyedropper and display the bottle with your project.
- Walrus, seals, and sea lions are pinnipeds (fin-footed). These creatures can use their fins to swim and to walk on land. Discover how other creatures move in water and in air and on land. Display pictures showing different ways that creatures move about.
Check It Out!
Some snakes move from side to side, while others move in a manner referred to as a caterpillar crawl. Find out how snakes make their way over the ground and through water.
Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state’s handbook of Science Safety.