h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

To me it is palpable proof of God's existence, a posteriori.

But why do womens' bums wiggle like that, and mens' don't? Y'know, like that http://www.youtube.com/watch?v=npJlqMdsAfM

High heels

I've definitely seen male bums wiggling (straight ones, I hasten to add) but that seems to depend on their nationality.

Something to do with the shape of the pelvis? And the distribution of fat?

That's a start, but I want to understand more about the anatomy and physiology of the phenomenon.

Possible explanations

1. You're looking at women's bums not mens.

2. Women tend to dress in a way that means their bum is more visible.

3. Women have wider hips for childbearing, which means that they naturally have an hourglass figure. The wider the hips the more chance the women has of having a heathly baby.

4. The men find this subconsciously attractive for obvious reasons.

Hmmm.

1. 50% true

2. Accentuated, maybe. Men and women both wear jeans, for instance, and perhaps the cut for a woman is different from that for a man, but men can wear tight jeans too. Their bums don't do the same thing.

3. Childbearing hips don't necessarily lead to an hourglass figure. There are several identifiable female body shapes, including (but not limited to) the triangle, the pear, the hourglass, the round. Different pelvic builds between the two sexes seems like a promising avenue though.

4. That's an evolutionary explanation for why it could be useful but not an anatomical/physiological explanation of how it works. I'm still curious about the mechanics.

I thought female bumwiggle was partly learned (I am a girl, many girls in life/on telly wiggle as they walk, therefore I must wiggle), partly high heels, which accentuate any wiggle going on, but then, I do know women who walk like dockers in heels, and partly to do with the wide pelvic girdle and the angle of the inner thigh tendons which mechanically means the pelvis must tilt slightly to allow the forward leg to touch the ground as it swings forward. Narrower pelvises don't cause this diagonal slant on the thigh tendons. To make sure the tendons are vertical (ie at their strongest) when a person transfers her whole weight onto that leg, therefore the pelvis must tilt down on that side. So wiggle. But it can be suppressed (women sometimes shuffle or 'cowboy walk' to keep their pelvis more stable. This can be to do with weight problems, being heavily pregnant, lack of fitness, or having been self-conscious about the wiggle and therefore are surpressing it). The wiggle is also relatively easy to imitate even if not mechanically necessary, so people with narrower pelvises can do it too.

The POINT of the wiggle, according to people like Desmond Morris and his interesting ilk, is to draw attention to the bottom and pelvis. And to one's high oestrogen levels (ie fertility). So it is biologically determined as 'sexy'. In our culture, men aren't really allowed to be sexy, as it considered feminine, and the Anglo-Saxons are SO hung up on gender-role, so they suppress wiggle, especially if straight. In cultures where men are 'allowed' to be sexy and flirty, there's a lot more wiggling.

I must say, I appreciate a little wiggle whatever the gender of the bottom. But massively exaggerated wiggle just looks comical.

Didn't Marilyn alter one of her shoe heels to accentuate the wiggle?

Then, as well as the wiggle, there's the sway. And the swing. And the sashay.

*wonders how her rear gets along*

B

You get an ology, you're a Gosho!


Um, yes men's bum do wiggle...UK men far less than Latin's men bums but it's all to do with the way people loosen the hips..UK men & to an extent UK women walk very stiffly from the top of the legs rather than loosening up and walking through the hips into the upper body there-by loosening everything up below and getting the wiggle there.

Watch how men dance Latin on Strictly Come Dancing...the professionals that is...and they move superbly well.

Teuchter


No, essentially anyone can be taught to walk with a wiggle...doing Cuban style Salsa and other Latin dances helps but you still have to know/be taught the mechanics of how to walk with a wiggle...

And I can safely say that women do like a wiggle on a man...it seems to be attractive to opposite sexes it just that men either don't try hard enough/it doesn't come that naturally to them/they think it might be a bit poofy...

And British men are naturally anal and uptight?

Yes...

Couldn't have got away with a word like 'poofy' when we were on the BBC.

I can wiggle my bottom...
Definately somethign to do with ones pelvis/hips, and also the way one's 'gait' works.... which is where the high heels things come in, its easier to wiggle ones behind if one is wearing shoes/boots with some kind of heel... shorter steps too I guess, as that alters the gait and how the hips swivel...

In 2004 there was a paper in nature developing a theory that humans evolved large buttocks (gluteus maximus) for efficient running in the African Savanah.

"Another of humankind's most distinctive features, the gluteus maximus muscle that comprises the buttocks, also helps establish humans as far more skilled runners than their ancestors: A quick look at fossil australopithecines reveals that their pelvises, like those of chimps, support only a modest gluteus maximus.

"Your gluteus maximus stabilizes your trunk as you lean forward in a run," Lieberman says. "A run is like a controlled fall, and the buttocks help to control it." "

http://www.eurekalert.org/pub_releases/2004-11/hu-erm111504.php

Here is a 2006 paper explaining the theory: http://dash.harvard.edu/bitstream/handle/1/3743645/2143.pdf?sequence=1

Which'll be why runners have such large arses then?

Sounds like buttocks to me.

How strange... I have rather tended, all my life, to go out of my way specifcally to avoid running... does this make my buttocks redundant?

I have been behind Olympic athlete Liz McColgan as she walked up a flight of stairs. Her gluteus maximus is quite small.

And pert.