07.30.07
Posted in Science
at 9:33 am
by Dave Badtke
Science News reports in its July 28th issue that there appears to be a correlation between sunlight, which increases with decreasing latitude, and multiple sclerosis.
A half-century ago, doctors from Europe and North America who spent time in central Africa were struck by the absence of multiple sclerosis there. Indeed, the farther from the equator people lived, the more prevalent multiple sclerosis (MS) seemed to become. Scandinavians faced a higher risk than most other people. Thus arose the “latitude hypothesis” of MS, suggesting that a lack of direct sunshine somehow contributed to the nerve-damaging immune malfunction underlying the disease.
Although the geographical connection was strong, says Michael J. Goldacre, an epidemiologist at the University of Oxford in England, “it seemed almost too obvious to be true.”
The problem with this hunch, of course, was that genes play a role as well. This was addressed by selecting Southern California twins who had been exposed to differing amounts of sun. Using a questionnaire, which seems more qualitative than quantitative, they asked about sun exposure when the twins were young. I suppose the issue was whether they preferred playing volleyball on the beach or reading. The results, though, are significant.
But a study from southern California now lends new credence to the sunshine theory of MS protection by removing a persistent confounder in such studies—the variability in people’s genes. The researchers sifted through a large database to find records of 179 sets of identical twins in which one had MS and the other didn’t. Estimating these individuals’ childhood sun exposures, the scientists found that the twins with MS on average had gotten less sun.
The study bolsters a 2003 report from Australia that associated greater sun exposure and a history of sunburns in childhood with reduced risk of MS. Also, Goldacre and his colleagues discovered in 2004 that people with MS were only half as likely as the general population to develop skin cancer—a condition linked with exposure to ultraviolet radiation.
“There’s clear evidence from multiple publications to suggest this is something that’s real,” says Avery August of Pennsylvania State University in University Park, an immunologist not part of these studies. “There’s a genetic component [to MS] but also an environmental component,” he says.
In the new study, epidemiologist Thomas M. Mack and his team at the University of Southern California in Los Angeles analyzed questionnaires that the twins had completed before 1993 to obtain data on childhood sun exposure. The surveys included questions about outdoor sports and time at the beach.
The twin who spent more time outdoors had a 25 to 57 percent lower risk of developing MS, depending on the activity recorded, the researchers report in the July 24 Neurology. The people without MS had spent significantly more time than their siblings sunbathing, beachcombing, and getting out on hot days.
During childhood, it’s a trade-off between skin cancer and MS. But the effect fades after adolescence, so when you’re older there’s no excuse to sunbathe.
“This is a very sound piece of work,” Goldacre says. “Dermatologists may feel that [advice to] spend some time in the sun is not a wholly welcome message. But it’s all a matter of this being good for you in small doses.”
Curiously, the latitude effect in MS seems to fade after adolescence. While this study and earlier ones hint that ultraviolet rays set a child’s immune system on a normal course for life, they don’t prove it, August says.
Specifically, the studies don’t show how sunshine would thwart the rogue immune attacks on nerves, which cause a loss of muscle coordination in MS patients.
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06.08.07
Posted in Column Ideas, Science
at 10:09 am
by Dave Badtke
The Pirahã (pronounced pee-da-HAN) of northwestern Brazil speak a language that is challenging linguistic theories. John Colapinto in the April 16 issue of The New Yorker writes that linguist Dan Everett, one of the first to learn the difficult Pirahã language, has concluded that Pirahã seems to lack some of the irreducible language elements that linguists have come to expect. In “Cultural Constraints on Grammar and Cognition in Pirahã,” Everett notes the “extreme simplicity of the tribe’s living conditions and culture,” which are reflected in their language:
The Pirahã, Everett wrote, have no numbers, no fixed color terms, no perfect tense, no deep memory, no tradition of art or drawing, and no words for ‘all,’ ‘each,’ ‘every,’ ‘most,’ or ‘few’ — terms of quantification believed by some linguists to be among the common building blocks of human cognition. [For a discussion of their number concepts, see the NPR Talk of the Nation program.] Everett’s most explosive claim, however, was that Pirahã displays no evidence of recursion, a linguistic operation that consists of inserting one phrase inside another of the same type, as when a speaker combines discrete thoughts (”the man is walking down the street,” “the man is wearing a top hat”) into a single sentence (”The man who is wearing a top hat is walking down the street”). (Colapinto 120)
The lack of recursion is particularly vexing because, as Colapinto points out, “Noam Chomsky, the influential linguistic theorist, has recently revised his theory of universal grammar, arguing that recursion is the cornerstone of all languages, and is possible because of a uniquely human capability.”
When I first listened to Pirahã speech at a religious site — interestingly, Everett started out as a Christian missionary who became a scientist because of his language abilities and exposure to the Pirahã — I had the impression that there were fewer sounds than one might expect, but I didn’t think that their speech sounded like singing as Everett has suggested. On the other hand, this recording was made for religious purposes, so perhaps the speaker was reading a script.
But then after listening to the excellent NPR piece on Everett, I was more fascinated. In addition to a brief discussion of the linguistic theories and the controversy Everett has stirred up, you hear the Pirahã speaking. Intriguing doesn’t begin to describe the nature of the exchanges. And then Everett demonstrates the flexibility of their language by saying a sentence, whistling it, and finally by humming the sentence. It’s amazing that these three forms convey the same information. And yes, indeed, the language does sound more like singing than speaking.
For more also see Dan Everett’s website at Illinois State.
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06.06.07
Posted in Science
at 1:32 pm
by Dave Badtke
In yesterday’s NY Times, Dennis Overbye comments on what he considers “one of the more depressing scientific papers” he has ever read:
If things keep going the way they are, Lawrence Krauss of Case Western Reserve University and Robert J. Scherrer of Vanderbilt University calculate, in 100 billion years the only galaxies left visible in the sky will be the half-dozen or so bound together gravitationally into what is known as the Local Group, which is not expanding and in fact will probably merge into one starry ball.
Unable to see any galaxies flying away, those astronomers will not know the universe is expanding and will think instead that they are back in the static island universe of Einstein. As the authors, who are physicists, write in a paper to be published in The Journal of Relativity and Gravitation, “observers in our ‘island universe’ will be fundamentally incapable of determining the true nature of the universe.”
That the universe would become increasingly cold and lightless was suggested in 1987 by mathematician George Ellis, who wrote that even ordinary expansion “would gradually carry most galaxies too far away to be seen, setting the stage for cosmic ignorance.”
In my youth it was still thought possible that the universe might collapse back onto itself. Remember those searches for missing mass in the hope that there would be enough to pull everything back, enough for another big bang, another rebirth of the universe, another chance for Shakespeare to explore Hamlet’s motives? Alas, the dastardly data, like discovering one’s parents playing Santa Claus late on Christmas Eve, have disproved the possibility.
Worse, the existence of dark energy accelerates the expansion process, meaning that this bleak future will happen sooner, though we won’t be here on earth wondering why there are fewer galaxies in the sky than grains of sand on the beach inasmuch as the earth will be consumed by the sun in a mere 5 billion years.
But might we be somewhere?
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06.03.07
Posted in People, Society, Science
at 10:31 pm
by Dave Badtke
In New York Times on May 31, Sam Brownback, one of the three Republicans to raise his hand against evolution during the first Republican presidential debate, is trying to do the kind of explaining one needs to do after apparently not learning even after all these years in office that he shouldn’t answer a question with a raised hand unless the query has to do with coffee and dessert after dinner, which can be a good idea if too much rubber chicken hasn’t been eaten. But instead, Brownback’s eating crow, trying to explain why he raised his hand.
Ours is a sound-bite political culture, Brownback claims — though one wonders why there are so many willing sound-bite participants — which creates a stark contrast that does a “disservice to the complexity of the interaction between science, faith and reason.” He feels that since religion and science strive to understand the truths of their respective worlds, a materialistic world in the case of science and spiritual world in the case of religion, the truths of each can be complementary, but not contradictory.
The heart of the issue is that we cannot drive a wedge between faith and reason. I believe wholeheartedly that there cannot be any contradiction between the two. The scientific method, based on reason, seeks to discover truths about the nature of the created order and how it operates, whereas faith deals with spiritual truths. The truths of science and faith are complementary: they deal with very different questions, but they do not contradict each other because the spiritual order and the material order were created by the same God.
If you’re hoping for some example of how having a common origin or initial condition — God — guarantees that two complementary things cannot be contradictory, you won’t find it because rational, evidence-based cause-and-effect relationships find little purchase in Brownback’s editorial. For example, one could certainly argue that in a marriage the partners complement one another. But does anyone really believe that because both were born of women that they don’t contradict one another? Well, you might say, my analogy is facetious, and you’d be right, but then it seems it’s Brownback’s problem that he neither chooses his terms carefully nor takes the time to carefully define what he’s talking about.
In any event, he gives no example, and in the next paragraph he states that “People of faith should be rational,” which is fine, but then states that reason “cannot answer every question,” which leads him to the disturbing conclusion that “Faith seeks to purify reason” so that we can see more clearly. “Faith supplements the scientific method by providing an understanding of values, meaning and purpose.” Diagrammatically, Brownback seems to be suggesting that the relationship between science and religion looks something like this, 
in which the truth that science finds is “purified” by religion. This could hardly be a more dangerous idea since one person’s purification is another’s propaganda or oppression. That there is a God is doubted by many or that there is a different kind of God from Brownback’s is believed by many more, but in either case a faith-based filter of science is doomed to fail because when scientists seek truth, their mathematics and modeling are not affected by ethical or religious considerations, which is not to say that they themselves are not so affected.
It’s critical to separate the search for scientific truth, which is not bound by ethics, from the scientist who performs the research, who is bound by ethics. As a result, the diagram above should be modified to reflect the filter that ethics and religion apply to the person to “purify” his or her thoughts, but not to the truths the scientist develops.
Within the scientific endeavor, the scientist discovers evidence-based truths. And in science something is the truth if and only if it is a carefully defined set of evaluated facts from which inferences can be made that quantitatively explain the past and predict the future. Physics does this in a Newtonian sense, for example, when it explains tides and solar eclipses, in an elementary particle sense when it explains the quantum properties of particles and fields, and in a flow and aerodynamic sense when it explains why birds, bees and Boeing 747s fly. Similarly, molecular biologists perform this kind of evidence- and model-based science when on a micro level they decode various genomes and discover that we and mice share 99% of the same genes. On a macro level, the evolution of our nervous system can be traced back to the much simpler structures found in worms and insects. And yes, monkeys do look and act like us, which you’ll discover if you spend any time with one.
Evolution, then, is a science as well established as the science underlying the various technologies we use every day from a toaster and cell phone to an automobile and airplane. The problem with evolution is, however, that it deals directly with us, with human development, and this has twisted the ideas of some in the religious community, like Brownback, into unsupportable intellectual knots.
He claims that “There is no single theory of evolution, as proponents of punctuated equilibrium and classical Darwinism continue to feud today” without understanding that the constant reevaluation of falsifiable scientific principles is the essential dynamic that drives scientific evolution much as natural selection drives biological evolution. But Brownback wants none of this dynamic if the assumption is that evolutionary theory offers a “vision of man as a kind of historical accident.”
Fortunately for science, unfortunately for Brownback, he has no say in the scientific debate unless he’s willing to participate as a scientist by assuming that his “truths” are falsifiable. Certainly he’s a senator capable of messing with the minds of Kansas children and children in other states, and that will take a terrible toll, but in the grand scheme of scientific evolution, his views will make no difference because those who pursue science will continue to discover truths whether the U.S. wants to participate or not.
Where he does have influence is in the ethical training of scientists, since this indeed is the filter that philosophy and religion apply to science. But that influence is weakened to the point of ineffectiveness if it is based on an unwillingness to understand the scientific process.
While no stone should be left unturned in seeking to discover the nature of man’s origins, we can say with conviction that we know with certainty at least part of the outcome. Man was not an accident and reflects an image and likeness unique in the created order. Those aspects of evolutionary theory compatible with this truthe are welcome addition to human knowledge. Aspects of these theories that undermine this truth, however, should be firmly rejected as an atheistic theology posing as science.
Sorry, Brownback, but if you want to participate in the scientific debate, you can never make such statements. Science will continue to evolve and answers will be found, and some of the answers will be horribly unethical, which is why it’s so important not to undermine ethical and religious training with principles that encourage people, especially children, to bury their heads in religious sands by claiming that scientific results can be rejected because someone believes them to be “atheistic.”
At times like these when some of our political leaders are behaving as though they can return us to the dark ages when Greek and Roman ideas were rejected, independent of their value, as pagan and corrupt, we need someone like Bob the Bird who can speak sense to nonsense. On this I will have much more to say in upcoming Benicia Herald articles.
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