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Some people use worms to go fishing-next time you’re at a pond, you can go fishing for worms. This experiment is great for capturing and observing planaria (plan-AIR-ree-uh). They’re worms that eat tiny pond critters. They’re small meat eaters.

What You Need

  1. a pond
  2. a length of sturdy thread
  3. small piece of raw liver or ground beef
  4. small jar
  5. magnifying glass

What You Do

  1. Tie the string around a small piece of meat.
  2. Dip your bait into the pond.
  3. Fill the jar with pond water.
  4. After a few minutes, slowly raise the meat out of the water, and gently lower it into the jar.
  5. Use a magnifying glass to see if you’ve caught some planaria! If not, try it again

What's Happening?

Planaria eat meat; we call meat-eating animals, “carnivores.” (KARN-ih-vohrz). The planaria smell in water the way we sense smells in air. They smell the meat and grab on. These carnivorous (kar-NIH-ver-us) worms have two “eyes” that can sense light, but their eyes can’t form clear images like human eyes. Planaria play the role of pond trash-collectors, scavenging and eating dead animals. There would be an awful pile-up in ponds if planaria weren’t around to clean up!

Muy Importante! (Very Important!) Always wash your hands with soap and water after handling raw meat and messing around in pond water. Tiny bacteria can live in uncooked meat and pond water. If you get a bunch of these bacteria inside you, sometimes it makes you sick.

Bill Nye