system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why are the hairs that grow in moles thicker and blacker?
gpt
Moles are basically a tumor. The unusual cell cluster pushes on the follicle, making it grow hair faster than usual. They're darker because of the extra melanin in the area from the mole. It's actually a good thing if your mole grows hair because that's a sign it's not cancerous.

I copy/pasted it from another ELI5 from a few months ago, credit goes to PurpleOrangeSkies.