How can protein filaments growing out of the scalp cause boys to be banned from school, men to be massacred and angels ordered to do a woman's bidding? Bruce Munro takes a closer look at hair.
When Taieri College pupil Kurtis Bain was told to stay away from school until he got his ''extreme'' haircut sorted, it touched a raw nerve.
The 15-year-old Dunedin resident, who turned up to school with a severe mullet and then with shaved back and sides and a healthy comb-over, was the second pupil in three months to be temporarily banned from a New Zealand school because of his hairstyle tastes.
In July, Lucan Battison, of Hastings, won a High Court ruling that his suspension for refusing to cut his hair was unlawful.
Just as Lucan's had before him, Kurtis' case drew strong public reaction.
It ranged from allegations the education system was exerting ''tight controls smothering any form of individuality'' to claims teenagers' hairstyles pointed to an ''absolute disdain for rules and regulations'' and calls not to blame the school for objecting to a haircut that did the wearer no favours.
As well as the ire of people on all sides, the issue has raised some searching questions about hair and hairstyles.
Why is what we do with our hair such an emotionally charged topic?
Why is our own hairstyle so important to us?
And why is it apparently of such intense interest to others?
University of Otago social anthropologist Associate Prof Jacqui Leckie says it is because our personal adornment, including our hair, can be ''a very powerful form of identity''.
Our hairdo, whether it is flowing Farah Fawcett locks or a Jason Statham shaved pate, a Helen Clark helmet or an Elvis Presley pompadour, is one of the key ways we say ''It's me. This is who I am''.
Robert McKenzie makes that statement with an Afro.
The Dunedin cleaner, of Scottish and Fijian extraction, used to sport a close-cropped haircut.
But that changed in February last year when he and a mate were having a drink.
A TV playing in the background caught their attention when a 1970s music video featuring a forgotten musician with a large Afro appeared on screen.
''My mate said, 'Why don't we grow our hair?','' Mr McKenzie recalls.
''I said, 'Well, why don't we have a bet on it and see who can grow the biggest Afro?'.''
And his hair has been growing like Topsy ever since.
''In Fiji, our ancestors all had big hair,'' he says.
''In the Pacific, we probably have the biggest, kinkiest hair.''
The larger a Fijian woman's hair, the more beautiful she was considered to be.
Here in Dunedin, Mr McKenzie started noticing his growing head of hair was also attracting attention.
''People would walk past or see me at the bus-stop and say, 'That's a mean Afro, man'.
''I thought, 'This is pretty good; people are talking to me'.''
Not only does the Afro give him a distinctive look, it is an ideal style for cooler climes.
''It's warmer than wearing a beanie,'' he says.
Now known to his teenage children's friends as Afro Man, Mr McKenzie is not setting any dates for a visit to the barber.
''I feel really good about my hair ... I want to see if the weight of it will finally make it drop over to one side.''
He plans to check in annually with his friend, who now lives in Australia, to compare growth rates.
•But a hairdo is not just about standing out from the crowd. It is also about defining ''us'' and ''them'', Prof Leckie says.
''It's the way we sometimes identify ourselves as belonging to something, and also the way we identify ourselves as being different from others,'' Prof Leckie says.
And whichever culture you identify as yours, it is likely to have spoken or unspoken codes defining how members should adorn themselves and wear their hair.
Among a certain brand of Pentecostalism, that means women growing their hair long so they can command angels.
Last week, University of Otago PhD candidate Sherrema Bower gave a public talk about her research into spiritual experiences of pentecostal women in New Zealand and the United States.
The anthropology student spent a year studying congregations in the Assembly of God (AOG) and United Pentecostal Church International (UPCI) denominations in both countries.
Ms Bower, formerly of the US, was raised in the UPCI but left it a decade ago.
The church has a particular way of interpreting some verses in the Bible - particularly the 11th chapter of the first book of Corinthians - which has implications for its women's hair, Ms Bower says.
In essence, the UPCI strongly encourages women not to cut their hair, as a sign of submission to family and church leaders and to God.
Googling ''pentecostal hair'' offers up dozens of images of women with extremely long, often curly, sometimes ankle-length hair.
But the submission is believed to bring with it power.
''If she has her hair uncut she is spiritually powerful,'' Ms Bower says.
''And that is because she has been obedient to the word of God. God is honour-bound to hear her prayer and to dispatch those angels mentioned in verse 10 to carry out what she is asking for.''
Hair, it seems, is often linked to power; be it spiritual, social or political.
In recent decades, the most celebrated and far-reaching example of hair's social and political power is the hippie flower-power era of the late 1960s and early 1970s.
And probably that era's most enduring memorial is Hair: The Tribal Love-Rock Musical.
Productions continue to be staged throughout the world, including in Ashburton in 2013 and Rotorua in May this year.
The controversial and influential stage show about bohemian New York youth colliding with Vietnam War conscription was a reflection of the revolutionary social forces at work at that time and the role hair played as they spilled over into the political arena.
''We knew this group of kids in the East Village who were dropping out and dodging the draft, and there were also lots of articles in the press about how kids were being kicked out of school for growing their hair long,'' Hair co-writer James Rado told the Los Angeles Times in 2001.
The US Supreme Court heard two cases involving the show. Bomb threats were made against theatres in some cities where it toured.
''We felt like we were changing the world one audience at a time,'' Jonathan Johnson, who was in early productions of Hair, said.
In New Zealand, hairstyles during the same period were helping reshape the socio-political landscape of this country, historian Barbara Brookes says.
In the 1970s, some men wore their hair long ''to signify a new vision of gender relations where women and men would share work and childcare'', Professor Brookes, of the University of Otago, says.
Feminists during those years were opting for long, natural locks over the conventional teased and hairsprayed coiffure.
Their chosen hairstyles ''rejected an artificial beauty culture that seemed to objectify women'', Prof Brookes says.
Among Maori of that period who were fighting to reassert the standing of their language and culture, some were looking to the civil rights movement in the US for inspiration.
There the ''Black is beautiful'' mantra led to rejection of chemical treatments to straighten kinky, or nappy, hair in favour of more natural Afro-style looks.
That was emulated by some Maori.
But the more significant hair-related change for Maori came after that, Dr Khyla Russell, of Otago Polytechnic, says.
For many Maori, the head is sacred.
So there are traditional protocols for dealing with anything associated with the head.
The Maori renaissance, which gained momentum in the 1980s, allowed old practices such as burning or burying cut hair to come back out in to the open, says Dr Russell, who is overseer of Maori research and course content at the Polytech.
More hairdressers are becoming aware of, and respecting, those traditions, she adds.
The politics of hairstyling was perhaps at its most dangerous in early 17th-century China.
The hairdo many Westerners think of as typical traditional Chinese - the queue, in which the hair on the front of the head is shaved off above the temples and the rest of the hair braided in a long pony tail - was in fact a symbol of violence and domination.
When the Manchu people conquered the ethnic majority Han, they forced all Han males to adopt their hairstyle as a sign of their defeat.
Those who refused were executed.
Tens, and perhaps hundreds, of thousands of people were killed.
• These days, in New Zealand, hair-related political deaths tend to be more figurative than literal.
Politicians can be massacred at the polls for not choosing the right hairstyle, personal stylist Stephanie Rumble, of Christchurch, says.
Politicians want to present themselves as sincere and trustworthy, Mrs Rumble says.
Because New Zealand voters tend to be conservative with their own appearance, anything that is too flamboyant or different is likely to be read as untrustworthy.
Former Green Party MP and dreadlocked Rastafarian Nandor Tanczos probably lost some votes simply through prejudice about his looks, Mrs Rumble says.
''You need your hair to be non-distracting,'' she tells political candidates.
For males over the age of 25 that includes not dyeing their hair, or ''you'll look like Mick Jagger''.
National leader John Key is doing a good job, keeping his hair short and letting it quietly go grey, she says.
His Labour counterpart David Cunliffe also rates well on that front.
And Gerry Brownlee?
''Well we don't look at his hair much, do we? '' Mrs Rumble says.
''There are other things about him that distract us.''
Murray McCully should definitely lose the comb-over.
''Comb-overs are a bad, bad look because they can flap in the breeze.''
Female politicians need to be careful to get the balance right, Mrs Rumble says.
Former Prime Minister Helen Clark was criticised for looking too masculine.
But appearing too feminine is not a vote-winner either.
''A little bit of softness can be helpful for a woman ... but not long, long hair, because you lose credibility if you look too girly.''
Judith Collins is in danger of falling into that trap, Mrs Rumble says.
Trying to please the majority severely limits the politician's hairdo menu. But for the rest of us the options seem almost endless.
Yes, there are rules for each of the myriad continually splintering subcultures, but simply pick the rules you like.
Saturday night's Bledisloe Cup-winning All Blacks illustrate it well.
Ma'a Nonu's serpentine braids look nothing like Richie McCaw's hedgehog spikes, which look nothing like Ben Franks' shiny bowling ball, which looks nothing like Brian Crotty's nouveau pioneer curls and beard, which look nothing like TJ Perenara's Macklemore-esque short back and sides with longer locks on top ... And the experimentation is starting much younger.
Julie Costello, a hairdressing tutor at Aoraki Polytechnic, in Dunedin, says today's young people ''all have an expectation of having their hair done professionally''.
So it is no surprise that as they have had their hair coiffed since
almost before they can remember, by the age of 15 the excitement of a tidy, professional cut is fading and they want something more daring.
When Kurtis first got his wide, thick mullet at the hairdresser's, the sides of his head still had a short covering of hair.
But he was keen to have some fun with it.
So, before going to school, he got his mates to shave the sides.
His friends thought the result was funny.
The school was less impressed.
He shaved the back of his head and then took some length off the remaining top crop before he got the official OK.
But those who look at Kurtis' hair and see rebellion and disrespect are reading much more into it than the cut itself allows.
The fillip for his hairstyle is a model of self-discipline, skill and achievement.
''I seen [sic] [someone] that had it and thought, `Oh yeah, that looked quite nice','' Kurtis says.
Choosing that hairstyle was the natural outworking of the deep human urge to use our hair to tell ourselves and the world who we are, what we value and where we are headed.
Kurtis' inspiration?
David Nyika, the young Commonwealth Games gold medal-winning New Zealand boxer.
