One of the experiments carried out for BBC's Horizon programme looked at people's preferences for hairy or hairless bodies
By Paul King
Once we were all happy to walk around naked, now we're not. But can an experiment in nudity help us understand why we are so embarrassed by being seen in the buff and help shed our inhibitions?
It's a classic anxiety nightmare - you're standing in front of a room full of work colleagues, your boss is there, maybe even that new colleague you've been trying to impress. And you're stark naked. Ouch.
Why are we so ashamed of being seen naked? Is there something deep in human nature that finds naked skin abhorrent? Some prudishness inherited from our Victorian ancestors?
FIND OUT MORE...
Horizon's What's the Problem With Nudity? is on BBC Two at 2100 GMT on Tuesday, 3 March
And how can you explain the rebels who shun convention to spend their weekends hanging out with similar-minded nudists, insisting nothing could be more normal?
Eight ordinary people - none of them nudists - were recently brought together for an experiment filmed by the BBC's Horizon programme, to test some of the scientific theories that explain why naked bodies make us so uncomfortable.
Among them were Phil, 39, from Birmingham and Kath, 40, from Dorset. Kath's greatest worry was that people would laugh at her. Some of the men in the group were more concerned about inappropriate excitement.
Phil was first to feel the cameras burning into his skin. A matter of hours after meeting the other volunteers, he found himself before a full-length mirror, instructed to remove all of his clothes. When he discovered the mirror was two-way and he was being watched, his red face, beating heart and soaring blood pressure told a story.
Performing the same task, Kath admitted she wanted "the floor to open up." When we are naked in public, most of us feel exposed.
All around the world individuals feel great shame when they know that others know that they have failed to be adequately modest
Prof Dan Fessler Psychologist
And of course, a naked human is just that bit more naked than other primates. We have only minimal body hair, they have fur. Why?
It's one of the greatest mysteries in evolution, and even bothered Charles Darwin. One of the theories is that we lost our fur as a way of dealing with the heat of the sun. It's controversial, as most mammals use fur to protect them from the sun. But some anthropologists believe our ancestors' unique ability to sweat, along with their upright stance, meant we could cool quicker without fur - prompting the onset of human nudity.
They reckon that evolutionary step towards nudity had huge implications for the human race. With a souped-up cooling system, our ancestors could afford to develop ever-bigger brains - leading to culture, tools, fire, and language.
Red for 'no-go'
"Really, without losing hair, without our sweatiness, we wouldn't have been able to evolve the big brains that characterise us today," says anthropologist Professor Nina Jablonski of Penn State University. "Essentially, being hairless was the key to much of human evolution."
So there's reason to believe our nudity arose out of practical need, but that doesn't answer why we're so ashamed by it.
Attitudes towards nakedness may be the result of the need for long-term pair bonding
But it seems this shame can be unlearned - witness, for example, the work of artist Spencer Tunick, who frequently corrals hundreds of volunteers to strip off en masse in public places for his photographs.
After a series of experiments, Phil and Kath, who had been so self-conscious at the start, each came face-to-face with a newly stripped fellow volunteer. They were invited to paint the body in front of them, colour coding every patch of skin to show how uncomfortable they felt touching that part of the body - red for no-go; yellow for squirming and green for fine.
Phil drew the line at colouring his subject's genitals, but Kath had lost all her inhibitions. Within moments she'd painted her subject completely green. Every inch.
It was an example of how flexible our attitudes to nudity are. And it explains how nudists can carry on as normal when they're surrounded by naked people. Over a couple of days, the volunteers had unlearned many of the social conventions that normally govern their life, and reached a new consensus that permitted them to be naked in each other's company.
It chimes with the psychologists' theory that we are not born with a shame of nudity. Instead we learn it, as an important behavioural code that allows us to operate in human society.
Some people may even find this image uncomfortable to view
With the long immature period of a young human, mum and dad need to form a stable pair bond to do the looking after. But humans are more social than any other primate, living and moving in large social groups.
Psychologist Professor Dan Fessler, of the University of California, Los Angeles, says our gregariousness "poses a challenge... because those groups of course provide a source of temptation. Potentially both sexes can benefit by cheating on their partners."
That's where our shame of nudity comes in. Over thousands of generations, we've learned that showing off a naked body sends out sexual signals that threaten the security of mating pairs. And we've chosen to agree that that is a bad thing.
Shame is the ideal emotion to enforce that code of conduct. Because it feels unpleasant, we avoid it at all costs. And because it's such a visible emotion, everyone around gets a clear message that you know you've messed up.
"All around the world individuals feel great shame when they know that others know that they have failed to be adequately modest," Prof Fessler says. "Essentially, they're signalling to those around them 'I understand what the social norm is and I understand that you know that I have failed in this regard, so please don't hurt me.'
"Nudity is a threat to the basic social contract. They have exposed their body and their sexual selves in a way that presents an opportunity for sexual behaviour outside of the principal union."
But as this code of conduct is something we learn, rather than are born with, we can re-learn it, if common consensus allows. As Phil reflected: "One thing I think I'll take away is how easy it was to bond with complete strangers in what should really be an artificial environment and one that by all society's standards we should feel uncomfortable with."
Would all this knowledge prepare Phil and Kath to push the boundaries of acceptable behaviour back in the real world? As the weekend drew to a close, they were presented their final, surprise challenge.
They are invited to walk naked in the street to waiting taxis, which they do. They have overcome a significant bit of socialisation.
Below is a selection of your comments.
It seems obvious to me. Humans invented clothes - at first simple animal skins, to protect them from the environment (cold mostly). Then, as we got better at making clothes and invented weaving etc, we became able to make clothes better fitting and began to make them more elaborate and ornate. Soon, clothes became a symbol of status - the more powerful you were the more able you were to have better clothes made for you. If having very good clothes was a symbol of status or honour, then wearing no clothes became a symbol of poverty and shame. Tim Hellis, Cardiff
There's a wonderful freedom being nude in a naturist area. Once you have swum in the nude you don't want to swim clothed again. Most people who are reluctant to go naked in nudist places, wonder why they were worried after they have done it. I have no problem with nudity in clothes optional environments, pity there weren't more. I don't think though I would want people wandering around shopping centres etc nude. D M, Glasgow
In my lifetime, people have become more prudish in one way. In gents' toilets, it is noticeable how younger men are more prone to using cubicles as opposed to urinals and it would not surprise me if I lived to see them disappear. Swimming pools built during the 1970s would normally have open plan changing areas, but more recent ones have enclosed cubicles. Although I have no experience of such an arrangement, I have been assured that clothes shops in the 1960s frequently had open plan changing areas. Interesting how we have become more tolerant of most things, public nudity seems to have gone the other way! Matthew Wyatt, Stevenage
I don't agree with the premise that "we" are "ashamed" to be naked. Neither were "we" once all happy to all walk around naked - maybe some of our ancestors were, but that's not us. A desire not to be naked is not to do with shame (where did you get that idea from?) it's to do with privacy - not to forget keeping our bodies warm and protected. I really can't understand where you got this "shame" thing from! It's such a pity too that so many reports etc use that word "we" as if we are all, without exception, included in whatever is being suggested. Philip, Kent
What is this recent phenomenon with the BBC and nakedness? What is wrong with having decency and humility in our lives? Why do we need to feel open about not wearing clothes? I hate the fact as it is, that when I go to the gym I'm usually greeted with a largely overweight gentleman's backside in the changing rooms. I'd hate for society to change so that everyone would have to put up with the same everywhere. Mohammed Khan, London
Sexual harassment is bad enough as it is. If I walked around naked, I'd be wolf-whistled on every street. Karen, London
For over 25 years I have enjoyed nothing more than being naked on naturist beaches and in the privacy of my garden. I do however have great respect for those who are offended by nudity and while I am not at all ashamed of my body, I would hate to offend anyone. I also believe those who flaunt their nudity are inconsiderate and selfish. Brian, Waterford
From where I'm sitting, watching the wind buffet the trees outside with a sub-zero wind-chill, there seems to me to be a much more compelling reason NOT to wander about in the nude. Also, just remember that if you do wander about naked you're likely to be placed immediately on the sex offenders' register - so far have we come from a society that can accept nudity! James, Dundee
In some countries it is normal to be nude in a sauna together with complete strangers and the normal accepted behaviour can be completely reversed: if somebody joins a group of naked people inside the sauna and is dressed (bathrobe, swimming costume) this is regarded as being outside the norm and can be embarrassing for the dressed person. Martin, Liverpool
Get all us fat wheezy Brits to run around naked? That will lead to a huge rise in vegetarianism which means less cattle and less methane. However, we will need a massive injection of cash into the NHS to cope with the increase in Post Traumatic Stress Syndrome. If you want a taster, think of Eastenders nude - Dot, Pat, Ian....yuk! Clive Gibson, Alnwick
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