Why and how do some hairs “know” when to stop growing (e.g. eyebrows, arms, eyelashes) while others (e.g. scalp, beard) doesn’t seem to?

Question

Is it that they don’t know or the “threshold” is so long that we don’t get to see it very often?

In: Biology

Answer 1

Your eyebrows stop growing? Must be fucking nice. If i dont trim em for like a week or two I have 90 year old man caterpillar eyebrows. Not bushy… booossshie mother fucking monsters