Why do people have hair on their arms/legs?

  • Thread starter Pengwuino
  • Start date
  • #1
Pengwuino
Gold Member
4,989
16
Why do people have hair on their arms/legs??? And why does it only seem to grow on half your arm?
 

Answers and Replies

  • #2
1,134
9
I think first would be for warmth. And being that the lower arms and legs are farthest away from the main body, hair should be a bit thicker there.
Its also a sensor for your nerves. I have a friend with alopecia{no hair at all} he gets more cuts, cause he dosen't have the pre-warning system.
 
Last edited:
  • #3
Monique
Staff Emeritus
Science Advisor
Gold Member
4,149
64
He gets cuts where?
 
  • #4
1,134
9
Just about everywhere that a normal person would of had that split second warning they are about to hit something. And that would include heat{burns}, that quick little singe of hair that warns us to back off.
 
  • #5
Astronuc
Staff Emeritus
Science Advisor
18,979
2,322
Pengwuino said:
Why do people have hair on their arms/legs??? And why does it only seem to grow on half your arm?
I expect that it is an adaptation. Here's an interesting article - http://en.wikipedia.org/wiki/Hair

I have seen some men with relatively dense hair on their upper arms and legs, and also their backs.

My legs have hair, and my forearms have hair, but not my upper arms. I have a fair amount of hair on my chest, and some on my abdomen, but probably not as much as brewnog. :biggrin: I think on my upper arms and legs, the fact that I wear clothes wears away the hair.

Of course, my face and scalp have a fair amount of hair. :biggrin:

My beard keeps my face and neck warm in winter and cool in the summer.
 
  • #6
Monique
Staff Emeritus
Science Advisor
Gold Member
4,149
64
hypatia said:
Just about everywhere that a normal person would of had that split second warning they are about to hit something. And that would include heat{burns}, that quick little singe of hair that warns us to back off.
Well, I don't know about your hypothesis :uhh: You'd have to have heavy long and curly hairs to notice anything! I can't imagine anyone having a split second warning that they are about to cut themselves with a knife because of the miserable little hairs on the top of your fingers. When you are already burning the hairs on your arms I'd think the heat of it would be a pretty good warning sign.
 
  • #7
Mk
1,984
3
I thought he meant with the hair on half the arm, about how you don't have hair on the bottom part of you arm. If you stick your arms out, palm-down, what's on the bottom, there is no hair.
 
  • #8
1,134
9
Monique, if you slightly touch the hairs on your arm, you feel it, no matter how short they are. And no I'm talking about cutting yourself with a knife, more like, brushing your leg near a ruff object..if you have hair on your leg..you get a warning.
And its not really my hypothesis, it what the guy told me when I noticed so many scars on him.
 
  • #9
Monique
Staff Emeritus
Science Advisor
Gold Member
4,149
64
But the hair on my arm are completely flat against my skin. The only difference could be that the signal is amplified by the hairs, since the hairs can move in different directions and thus sensitizes the skin.

So let's do a study: who of the women here at this forum don't shave/wax their arm/leg hair and do they have extra scarring?
 
  • #10
9
0
where do you have most hair except ur head ?
 
  • #11
Moonbear
Staff Emeritus
Science Advisor
Gold Member
11,490
52
hypatia said:
Monique, if you slightly touch the hairs on your arm, you feel it, no matter how short they are. And no I'm talking about cutting yourself with a knife, more like, brushing your leg near a ruff object..if you have hair on your leg..you get a warning.
And its not really my hypothesis, it what the guy told me when I noticed so many scars on him.
I don't suddenly get more cuts on my legs when I shave them, and competitive body-builders shave their entire bodies without winding up covered in cuts and scrapes. :confused: By the time you're brushing the hairs on your body, it seems too late to do anything much about it. I think your friend is more likely just a bit more klutzy than the rest of us and is trying to make excuses.
 

Related Threads on Why do people have hair on their arms/legs?

Replies
33
Views
13K
Replies
4
Views
22K
Replies
1
Views
2K
Replies
12
Views
7K
  • Last Post
Replies
15
Views
48K
Replies
7
Views
8K
  • Last Post
Replies
10
Views
19K
  • Last Post
Replies
1
Views
3K
Replies
2
Views
4K
Top