system
Given the following post, respond as if you're commenting on Reddit:
human
Why do worms come out of the ground onto the footpath when it's raining?

Whenever it rains, the footpaths in my neighbourhood are covered with *hundreds* of worms. Why do they come out of the dirt to lay on these hard wet surfaces?
gpt
Worms actually breathe through their skin and they have to stay wet or moist so oxygen can be absorbed. When it rains and the normally dry surfaces are covered in water, it gives them opportunity to go where they otherwise can't.