Thursday, March 26, 2009

Natural wonders

by Martín Bonfil Olivera
Published on Milenio Diario, March 25, 2009

I have just been to one of the 13 wonders of Mexico: the basalt prisms of Santa María Regla, in the state of Hidalgo.

When he came to Mexico in 1803, Alexander von Humboldt visited these impressive 30 meter basalt columns, of perfec hexagonal shape, that border a ravine as if God had arranged them like giants pencils. They're breathtaking.

But for a naturalist such as Humboldt, and for a relentless atheist like this columnist, the divine explanation is not satisfactory: it doesn't really explain anything. Could there be a natural process that allows hundreds of hexagonal prisms to be formed and carefully stacked ?

Basalt prisms, although rare, are not unique. There are 10 or 15 sites in the world with similar structures: the “giant's causeway”, in Ireland; the “Devils postpile”, in California; the “organ pipes”, in Australia… The formation of these structures doesn't seem to be that difficult.

A second hint is the hexagonal shape of the prisms. There is an old saying in northern Mexico, "as the wagon moves, the watermelons arrange themselves", that accurately applies to this case: spheres tend to accommodate spontaneously so that each one is surrounded by twelve more: it is the most compact arrangement. In the case of circles, the most efficient arrangement is hexagonal: the most compact form to arrange cylindrical columns is so that each one is surrounded by other 6. The hexagonal shape of the prisms is the result of this arrangement. They weren’t constructed and then arranged: they formed in their actual position.

And how could melted lava —basalt is solidified magma— form individual vertical prisms? The answer relies in the existence of self- organized structures in nature. "Bénard cells" are example : when heating a liquid from below, the convection movement —hot water goes up and cold goes down— can form hexagonal columns of water that keep circulating as long as there's a temperature difference. Prisms are fossilized convection cells that were solidified when they quickly cooled down.

The mineral world can form marvelous and arranged structures. The same thing occurs, but augmented, in the living world. Darwin, another naturalist, saw it and explained it. Because of this, and more the basalt prisms of Hidalgo are really worth visiting.

(Take a look at my pictures of the basalt prisms here)

(translated by Adrián Robles Benavides)

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Thursday, March 19, 2009

Scientific pyramids

by Martín Bonfil Olivera
Published on Milenio Diario, March 18, 2009

In view of Bernard Madoff's financial fraud scandal (not really a "pyramid", because it did'nt have levels; it was a "Ponzi scheme", since Maddoff was in direct contact with all his victims) one could ask wheter similar cases happen in science.

In his classic book The demon haunted world, astronomer and science writer Carl Sagan explains that "science requires the free interchange of ideas; its values are opposed to secrecy."

Values that, he adds, that it shares with democracy.

Such a system is necessarily based on trust. And where there's trust, there can be fraud. Last Thursday, in this same space, mi friend Horacio Salazar talked about how a single dishonest scientist can place at risk a whole area of science (in this case, algiology, the study of pain, where it was discovered that at least 21 research articles by Scott Reuben, a renowned  anesthesiologist, contained fake data).

Although science has some quality control mechanisms, such as the peer review process all articles undergo before being published, it's impossible to check every minute detail. And since the evaluation and salary system for researchers demands as many articles as possible ("publish o perish"), the temptation —and the opportunity— for frauds is always at hand.

On the same Thursday, scholar Wietse de Vries, from Puebla's Autonomous University reflects in Milenio Campus supplement about the similarity between the "academic publication industry", based on trust, with a Ponzi scheme (named after Charles Ponzi, the Italian immigrant that discovered how easy it was make frauds thanks to the trust of his fellow citizens and the rules of the financial system, which allows people to get rich not with money, but with the promise of money, as explained by Carlos Mota also on Thursday on Milenio.

Researchers, de Vries explains, write articles which are evaluated by their colleagues (and vice versa); then these colleagues quote, in their own articles, the articles they've reviewed. The system rewards publications and quotes: the more there are, the more benefit for everyone involved.

I'm not sure whether de Vries's analogy is well founded, but it wouldn't do any harm for scientists to  review —they're already doing it— their evaluation and fraud control systems.

(Figure: taken from PhD Comics, Jorge Cham's great comic strip about graduate student life)

(translated by Adrián Robles Benavides)

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Thursday, March 12, 2009

Women and washing machines

by Martín Bonfil Olivera
Published in
Milenio Diario, March 11, 2009

In 2006, in a tour in the Mexican state of Sinaloa, former president Vicente Fox proudly mentioned that seventy-five per cent of the homes in Mexico have a washing machine, "and made of metal, not the kind with two hands and two legs". This injurious phrase showed that the former president's concept of woman reduced to "a person that washes clothes".

Last Sunday, International Women's Day, pope Benedict XVI asked for women "to be more respected and valued every day". The same day, The Vatican's official newspaper, L'Osservatore Romano, published that women should give thanks for the washing machine because "this humble domestic appliance had done more for the women’s liberation movement than the contraceptive pill". Apparently, the Vatican values women more or less as much as Fox.

It's true that scientific-technological products –including washing machines, among other domestic without which housework would be worse than it already is– have contributed to diminish social inequality between man and woman (which still persists). What's indignant is to find people that still think that such labors are a natural obligation on women.

But it's undeniable that the fact that women, for the first time in history, are able to reliably control their pregnancies was one of the triggers of the revolution that radically changed their role in society –although, there's still way to go. Chemist Carl Djerassi, one of the fathers of the pill, reflects on these and other social consequences of his invention in his excellent book This man's pill.

On the other hand, science writer Ana María Sánchez Mora , in a penetrating book that should've been named Feminism and science popularization, but because of a bad editorial decision carries the ambiguous name Science and sex (La ciencia y el sexo), explains how science, apart from refuting some beliefs like witchcraft or the biological inferiority of women, of ending women's deaths from puerperal fever and producing the pill, gave women the knowledge and arguments to denounce and fight discrimination and abuses against them.

Science not only makes useful products. It also changes the way we see the world.

(translated by Adrián Robles Benavides)

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Thursday, March 5, 2009

Do species exist?

by Martín Bonfil Olivera
Published on
Milenio Diario, March 4, 2009

Lots of people find their fun trying to demonstrate that science's big theories are wrong. Einstein's relativity and Darwin's evolution by natural selection are two old time favorites.

Since science does not offer absolute truths, but simply knowledge that is reliable and useful, but that is in constant evolution, there's always the possibility that these critics are right. However, the usual thing is that, to begin with, they don’t have a good understanding of the theories they intend to overthrow.

One of the most common misunderstandings of Darwin's theory is the definition of a biological species. His book On the origin of species shows how they emerge, but Darwin's explanation —the varieties that appear within the same species are actually "incipient species" which, little by little, can get separated from the original— sound looks confusing. A species turns into another? When can we precisely talk about a new species? What is the difference between species, subspecies, varieties and race?

The problem is that we do not normally think in terms of populations, but of individuals. A friend of mine says he is convinced that there had to be a first human being, born from a "still not human" mother. He thinks that between both species —human and pre-human— there is a well defined border that can be crossed in one step (like the mutation that originated the Ninja Turtles)

The idea is not a dumb one: these first individuals of a new species were known as "hopeful monsters" for a long time. But, although their existence is possible, they are extremely rare cases. The normal way of things in evolution, by far, is the gradual accumulation of minimum changes that make the task of defining when a variety turns into a new species as hard as saying with precision just how many hairs a man must loose to call him bald.

In his revealing book Darwin's dangerous idea, philosopher Daniel Dennett explains that in reality, what allow us to distinguish between one species and another is the absence of intermediate individuals between two populations. When there is continuity between both, we realize that the definition of species is, in reality, a human abstraction. We'll talk more about this.

(translated by Adrián Robles Benavides)

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