Shave the hair on your head and it will grow to be two feet long. Shave the hair on your arm and somehow the hair knows when to stop growing to match the length of the surrounding hairs. The hair is dead the follicle is alive yet the hair seems to communicate to the follicle that "everything looks good from up here" and tells the follicle to stop growing or let the hair fall out. How does this communication happen and how does the follicle know its hair has been shaven and know when to start growing again?
How is body hair aware of its length?
shave it again no problem
How is body hair aware of its length?
hair dont stop growing.
short or long, its continue growing
It could be the solicitation of the hair strands to their follicles due to their weight/mass. The longer the hair, the more its mass and the more any single movement stimulates the follicle in a different way depending on its length so the body realizes how long it is and how much of it has been cut. More so independently from the gravity, something with more mass have more inertia, hence more pull and tug to the hair follicle. In any situation we have some minimal movement so that the body knows how long are our body and head hair, maybe it doesn't need to really "see" the hair panoramic. Think about how much force is needed to stop a truck and how much is needed to stop a motorcycle at the same speed, the truck always "wins", so once a hair exceeds the inertia for which a follicle is programmed to deal with, the body sends a hormonal signal to stop hair production and trigger its, rest, the opposite happens if the hair is cut, the follicle realizes it has less mass applied to the "bed". It's also a myth that hair grows back thicker when shaved, it just has its blunt end.
ReplyDeleteObviously all hair, besides a part of the head hair (not even all of them) of some people, is eventually shed off, but obviously they are programmed to live much more that the time needed to reach their length. At least a few times their length, as you see them all growing back when you shave them.