Students will learn how magnetic forces affect the navigation ability sea turtle hatchlings.
The earth's true magnetic North pole lies in north Canada. When people think of the North Pole they are actually thinking of the geographical North Pole, the point around which our earth rotates. The magnetic field produced at the true magnetic poles is an invisible force. This earth's magnetic field protects the earth from radiation given off by our sun. This field affects many organisms on earth. One of the most visible effects is observed during the migration of animals. Animals use the earth's magnetic field to find their nesting grounds. Rocks, soil and sand contain small particles of magnetite. Migrating animals have magnetite crystals deep within their brains. By combining the magnetite in their brain and the magnetite in substrate, some animals are able to locate their place of birth by picking up on the subtle magnetic fields produced by specific levels of magnetite in soil, sand and the rock typical to their habitat.
When an iron or steel rod is magnetized it will have both a North and South Pole. When two like poles are aimed toward each other they will (repel) move away. When two unlike poles are aimed toward each other they will (attract) move towards each other. A compass can be constructed if a needle is magnetized by rubbing it against a magnet and placed on a floating surface.
2 steel or iron pins
1 cork disk or a foam plate
1. Magnetize a sewing needle or pin by stroking it with a magnet.
2. Cut out the hatchling pattern provided. Cut a piece of cork or foam plate and glue the hatchling to it.
3. Push your magnetized pin into you turtle.
4. Place your hatchling in a dish of water. Place your second magnetized pin at the opposite end of your dish and observe what happens.
- Cut out the hatchling pattern provided. Cut a piece of cork or foam plate and glue the hatchling to it.
- Place a paper clip on the head of your hatchling and use the magnet to attract it to the opposite end of the dish.