Send us your questions. Dr. Francis Rogers is a doctor who studies animals. Today's topic is the common earthworm.

Why do I sometimes see earthworms on the sidewalk after raining? It's really awful to clean them off my shoes. I've heard that they die if their holes are filled with water.

Earthworms breathe (呼吸) through their skin, but they're also able to live for a long time in water. Scientists think that earthworms leave their holes because the rain hits the ground.

I've been thinking about starting an earthworm farm. I can make lots of money by selling them to fishermen. I've heard that if I cut one in half, each half will grow into another worm. If this is true, I'll be rich in no time.

I hope you haven't started cutting yet. That's only a playground legend. If you cut a worm in half, one half will die and the other half, with the head, may be dead too. Put your knife away and feed your earthworms a lot instead.

Do some people really eat earthworms and why would they want to?

Please don't throw up, but many people do eat earthworms. In some places, people eat earthworm pies. In other parts of the world, people fry them and some even eat them without cooking. Earthworms are low in fat and high in protein. They're healthier than eating beef.