Thursday, December 20, 2007

moving to the north



Humans carry a lot of cultural baggage when it comes to skin colour, but to scientists it is increasingly a simple matter of a vitamin.

Around the world, scientists have observed that the farther human communities live from the equator, the lighter their skin colour tends to be - the result of an evolutionary adaptation related to vitamin D synthesis.

At higher latitudes, such as those prevailing in Northern Europe, it's only possible for people to make vitamin D the natural way - through skin exposed to ultraviolet sunlight - during spring and summer. That means over time there was an evolutionary advantage for humans living in these areas to develop lower levels of melanin, the natural sunscreen that gives skin its dark pigmentation, but causes reduced production of the vitamin.

By developing lighter-coloured skin, humans in northern parts of the world were able to make more use of the available sunlight for vitamin D production and build up stores of the nutrient for the long period during winter when light is too feeble to make any of it.

Esteban Parra, an anthropologist at the University of Toronto, says there are a number of competing scientific hypotheses for differences in skin colour, but the vitamin D explanation, and the need to have protection against ultraviolet light in the tropics, appears to make the most sense.

The impact of having lower levels of melanin, or lighter skin colour, is huge, when it comes to the synthesis of vitamin D.

It would take someone with dark skin of African or South Asian ancestry about 60 minutes at the same time of day to make the amount of vitamin D that a person of European ancestry would make in about 10 minutes, estimates Reinhold Vieth, one of Canada's top vitamin D experts and a professor in the department of nutritional sciences at the University of Toronto.

He says a rough rule of thumb is that people can only make vitamin D when the sun gets high enough in the sky that their shadows are shorter than they are tall, explaining why Canadians can't make any during the winter.

Although light skin hue is an advantage in northern areas, the opposite is true in tropical and subtropical regions because of the more intense ultraviolet sunlight, which allows for year-round vitamin D production, but holds other health risks.

There, having higher levels of melanin offers protection against the damaging effects of ultraviolet light - sunburn and lowering of folate levels, an essential nutrient that is destroyed by exposure to strong sunshine.

With people of different racial backgrounds now living around the world, health implications are emerging from these evolutionary adaptations to sunlight.

Whites living in tropical or extremely sunny areas, such as Australia, are at elevated risk of skin cancer and need to take sensible precautions against sunburn.

But non-whites are at higher risk of not being able to make enough vitamin D if they live outside the tropics and subtropics.


I got a very nice photography book from a friend for christmas. To remember my Japanese roots. The photography is erotic and deviant so I don't recommended it for the faint of heart.

Thursday, December 13, 2007

Top Ten scientific discoveries

As Time magazine sees it, the top 10 scientific discoveries of 2007

1. Stem cell breakthroughs
2. Human mapped
3. Brightest supernova recorded
4. Hundreds of new species
5. Building a human heart valve
6. Hot jupiters discovered
7. A big birdlike dinosaur
8. Man's migration out of Africa
9. The world's oldest animal
10. Real-life kryptonite

Man's migration out of Africa also relates to the human genographic project, where they found the location where races diverged. Man originated in Africa, some 60,000 years ago and Asian people and caucasian people split off in the middle east. Seems obvious when you look at people and the similarities held in facial features.

All of this was done by sequencing mitochondrial DNA, which is passed on directly from the mother so it is possible to trace a genetic history.

Top 10 scientific discoveries

The human genographic project

Tuesday, December 11, 2007

letters to the editor

I've written 89 pages so far and my brain has been milked dry.

While procastinating, I wrote a letter to the editor of SCMP. The ended up publishing a severely edited version.

In response to a previous letter regarding the level of science education in Hong Kong, I agree that it is a shame that there isn’t more funding available for students to learn the practical side of science. Being a PhD student at the University of Hong Kong, I would hope that my children would have the opportunity to learn the practical side of science. This would require a laboratory equipped with the apparatus for experiments to facilitate an understanding of ‘how things work’ and how to apply that knowledge creatively. Science has been progressing at a rapid rate in the past decade and high school education needs to account for it.

However with this letter, I would like to state there is little point in pursuing a career in science in Hong Kong. Yes, this is a cosmopolitan world city, but hardly a place for nurturing scientific talent. From 2000-2005, Singapore and Japan invested 2.25% and 3.14% of GDP in R&D per year, respectively, compared with Hong Kong's reported figure of 0.60%. To put this in perspective, HK spends proportionately less on R&D than Malaysia, Bangladesh, Nepal, Uganda and Morocco. The PhD student stipend at HKU has decreased more than 20% since 1998. The reality of a career in science is that 10 years of your life will be spent contributing to a better understanding of the cognitive world. Then by the time you have received a doctorate, you have no savings and you will feel like a career in retail or foodservice would’ve held more promise. Actually I don’t feel all that, but I am trying to make a point. However, if I did have a child, I would tell them to steer clear of science and go into another field where passion, tenacity, creativity and innovation are valued in today’s society. Science throughout history has had a checkered reputation indeed, but for much of the Twentieth Century, it was hallowed educational ground, and top scientists really enjoyed rock-star status. Whilst this is still somewhat the case in Europe and the USA, it has been tempered a good deal. In Hong Kong, however, it would be pure delusion.

I still believe in science and I respect the accomplishments that have been and continue to be made. Advances in science directly affect how we experience life. So why is it that society places such little value on it? Perhaps it is too abstract; scientists only have to communicate with other scientists, but rarely with the public. Like any sector, it should be marketed to gain appeal. Or perhaps scientists don’t bother complaining. It would be interesting if the local (because they do in other parts of the world) hospital and university staff went on strike in the same way as Hollywood writers or ESF teachers, perhaps in the wake of the next outbreak. However, the fact remains, that this government should invest more in research and development; create platforms for seeding new biotech or knowledge service spin-off companies that could capture new markets in China. Entrepreneurial enterprise should be nurtured with more effort should be made to commercialize such knowledge. And of course, the people that have committed to this field should be rewarded appropriately.

Tuesday, December 4, 2007


I've just been introduced to dubstep - reggae, drum n' bass influenced electronic music after listening to the Burial - Untrue CD. It's well produced with soulful vocals - that are broken, distorted and edited so it becomes part of the music, like another instrument, which works for me because I can't listen to lyrics while writing. Don't know why but London underground music is so much better than what they have here in um.. Hong Kong.

Sunday, December 2, 2007

World Aids Day

World Aids Day.. HIV has been around for more than 20 years and there is no cure. There are presently 39+ million people living with HIV with 4.5 million newly infected people each year. There have been some advances made- reducing the transmission rate from mothers to babies, the revelation that circumcision reduces the rate of transmission, development of new therapies. This is actually a preventable disease which means that in an ideal world, HIV could be eradicated within 1 generation. but there has been a general mis-education of the public since it's advent and prevention conflicts with certain cultural practices.

HIV is growing in Asia- in China and southeast Asia. There needs to be more emphasis on prevention and education, a better approach than waiting for pharmaceutical companies to develop drugs that will be too expensive for the majority anyway.

Saturday, December 1, 2007

Terry Richardson

Art again. It's always interesting to get the impressions afterwards- like 'Who buy's this crap?". I actually like his photographs but then again I find 70s porn amusing- I appreciate that it doesn't take itself too seriously.