Free Never Mind the Bullocks, Here's the Science by Karl Kruszelnicki Page B

move as a single unit, while the strands in straight hair tend to move individually?
    The ‘worst’ hair for tangling is dry, fine, chemically treated hair. With this type of hair, perhaps the scales stick to each other very easily? Unfortunately, this early model does not yet account for this fine detail.
Why is Pubic Hair Curly?
This question came up on the Triple J Science Talkback show. I was perfectly honest, and said that I did not know, but that I would go looking for an answer.
I came up with a whole bunch of potential reasons. Obviously, not all of them would carry the same weight, and some of them could even be wrong. But, for better or for worse, here are some of them:
     
Maybe because pubic hair is located in a warmish moist environment, and is scrunched up all the time.
Maybe it’s caused by the sulphur in the proteins that make up the keratin in hair. Pubic hair possibly has more sulphur, and this sulphur can carry a charge, which can give the proteins in hair a ‘twist’. Perhaps this ‘twist’ gets carried up from the micro scale to the macro scale.
Maybe it’s caused by the shape of the hair shaft. Apparently, in cross section, the shape of scalp hair is a circle – so it will resist a bending force equally well in all directions. And again, apparently, the cross-sectional shape of pubic hair is like an oval. In the longer direction, this cross section is very strong and quite resistant to bending, but in the shorter direction it is quite weak and susceptible to bending. Anyhow, for what it’s worth, this is another possible (but not necessarily true) reason.
The sex hormones act on the hair follicles in the genitals to make them generate curly hair – perhaps via oval exit holes for the hair.
Perhaps curly hairs trap pheromones (hormones that leave the body to travel to another body).
Perhaps pubic hair is curly to stop it poking you in the eye…
…and other silly reasons.
Anyhow, the next week I came back on air and ran through these ideas hoping that the truth was somewhere in there…
But then a sex worker from Kings Cross phoned in to Triple J and said that she had noticed (in her line of work) that Asians tended to have straight pubic hair. And the next phone call was from a sports coach who was shepherding a group of Japanese sportsmen around Australia. He had noticed in the showers that they had straight pubic hair. And he said that his female counterpart had noticed the same phenomenon in the Japanese sportswomen travelling with them.
So my line of thought was limited by my Western point of view. But, seeing as how pubic hair is becoming a thing of the past with all the Brazilian waxes going on down there – as opposed to out there – this research may never get the public attention it deserves.
    We still don’t know where this research will take us. But perhaps it will lead to better Velcro-type materials, because Velcro involves hairy fibres crossing each other and hopefully getting entangled. Or perhaps the large hair product companies will swing the resources of their massive laboratories to finally solving the vexing problem of tangling hair. After all, the problem of tangled hair is a curly one…Or perhaps they aren’t too fussed about splitting hairs!
    References
    Kunzig, Robert, ‘The biology of…hair: zeroing in on the molecular switches that regulate hair growth’, Discover , February 2002.
    Masson, Jean-Baptiste, ‘Why does curly hair get less tangled than straight hair’, American Journal of Physics , August 2007, Volume 75, Issue 8, pp 701-706.
    Nicholson, Christie, ‘Straight hair is knottier than curly hair’, Scientific American , 13 March 2008.

Flat Earth
(The Truth is on the Horizon)
    There are many false perceptions about what happened in bygone eras. One of the most common ones is that before Columbus, everybody believed that the world was flat. This is not so! The inhabitants of Medieval Europe (back in the 15th century) did not believe that the Earth