Why don't we live in human shaped skin bags?

October 28, 2007 9:27 AM

OK, Sunday morning stream of consciousness ended up with me wondering about skin or more specifically, loose skin.

You see humans have tight skin that doesn't really move over the body, like it's attached pretty strongly, whereas dogs, cats, bears, errr, other furry critters have skin that kind of rolls over their body. You can pick a dog or cat up by the scruff for instance, not so much a human. I had a look about on the internet and there seems to be a dearth of information on this important subject.

So Mefites, why do some mammals i.e. us, have the well attached skin while the dogs and cats have a kind of loose bag of skin that their body goes in? Is it an evolutionary thing that as you get closer to humans on the scale, the skin gets tighter? Do chimps have skin like us or them?

This is what Sundays are for surely?

posted by merocet to science & nature (6 comments total)

I think non-human mammals use that loose skin to pick up their youngsters by. That could explain it.
posted by mpls2 at 9:44 AM on October 28, 2007

Maybe it's a predatory defense trait-- a predator attacking a loose skinned animal will get a mouthful of skin that might tear away in a life or death struggle instead of clamping down on a vital organ. Bears hibernate (or used to, back when we had winters), they stored a lot of extra fat to use. Over 40, plenty of humans have looser skin than they'd care to admit.
posted by 45moore45 at 9:52 AM on October 28, 2007

It might have a lot to do with our body fat percentage. Humans eat a lot of crap, while animals in the wild and even domesticated, eat a very different kind of diet than we do.

I've noticed that my athlete friends have this sort of loose skin, while I (as a pudgy girl) do not. In gym class back in high school my PE teacher used body fat calipers to test everyone in the class -- I also remember a big difference between the scrub of skin he was able to pull up off of himself (thin and elastic) vs. the one I was able to pull off of myself (thick and pinchy).
posted by cior at 9:55 AM on October 28, 2007

The main thing that comes to mind is how mother animals can carry their babies by the scruff. Perhaps, it's an evolutionary thing since we can use our hands. I did read somewhere that human skin can support 90 pounds per square inch which is how suspensionists can get away with it without permenantly damaging themselves.
posted by adustum at 11:18 AM on October 28, 2007

Weight loss from morbid obesity can result in significantly loose skin.
posted by WCityMike at 1:14 PM on October 28, 2007

You might be interested in reading about fascia
posted by goshling at 3:57 PM on October 30, 2007