ELi5: Why do so many worms appear on roads, sidewalks, driveways, etc. after it rains?

Question

ELi5: Why do so many worms appear on roads, sidewalks, driveways, etc. after it rains?

In: Earth Science

Answer 1

All insects need air to breathe, even if they have no lungs. When it rains the water will soak into the ground displacing the air. So in order to prevent drowning the worms have to dig upwards and up to the surface where there is air to breathe. And while moving around on the surface looking for high ground some of them end up on the relatively dry roads.