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Wednesday, July 02, 2008

Henry Morgentaler Receives Order of Canada

 
Dr. Henry Morgentaler is a Canadian physician who campaigned for a woman's right to choose abortion. He is responsible for overthrowing the laws against abortion in Canada. Here's the entry in Wikipedia [Henry Morgentaler].
On June 1, 1970, Morgentaler was arrested in Montreal for performing illegal abortions. ... He was acquitted by a jury in the court case, but the acquittal was overturned by five judges on the Quebec Court of Appeal in 1974. He went to prison, appealed, and was again acquitted. Morgentaler first went to the Supreme Court of Canada in an attempt to overturn the country's abortion law in Morgentaler v. The Queen but was unsuccessful.

In 1982, the Canadian Charter of Rights and Freedoms was enacted as part of the Canadian Constitution. Morgentaler was charged again in 1983 in Ontario for procuring illegal miscarriages. He was acquitted by a jury, but the verdict was reversed by the Ontario Court of Appeal. The case was then sent to the Supreme Court of Canada. He was acquitted once again, and the Canadian Supreme Court declared the law he was convicted under to be in violation of the Charter and thus unconstitutional in the case of Morgentaler et al. v. Her Majesty The Queen 1988 (1 S.C.R. 30). This ruling essentially ended all statutory restrictions on abortion in Canada.
Yesterday, Canada Day, Morgentaler was named to the Order of Canada in recognition of his service to women and to the country. Canadian Cynic has a funny posting about the discussion that might have gone on when the committee was making up it's mind about Morgentaler [Fly on the wall, Order of Canada edition]

As you can imagine, not everyone in Canada is pleased about this award. The (Not Progressive) Conservative government under Prime Minister Stephen Harper was among the first opponents of women's rights to speak out as reported in the Globe & Mail [Cheers, jeers greet Morgentaler's honour].
The Harper government was quick to distance itself from the announcement that Henry Morgentaler, the controversial abortion doctor who changed the face of health care in the country, was named on Tuesday to the Order of Canada.

The Tories, no doubt sensing a brewing backlash from their conservative base, issued a brief response outlining how the appointment process has nothing to do with the government.

“The Conservative government is not involved in either deliberations or decisions with respect to which individuals are appointed to the Order of Canada,” the PMO statement said.
On the other hand,
But Liberal Leader Stéphane Dion called for politics to be put aside and asked Canadians to look at Dr. Morgentaler's contributions to society.

“Dr. Morgentaler has stood up for a woman's right to choose for his entire career, often at great personal cost and risk,” Mr. Dion's office said in a statement. “The Order of Canada process has been designed to keep politics out of it and I think we should all respect and celebrate the decisions of the panel and the Governor-General.”


Nobel Laureate: Sir Frederick Hopkins

 

The Nobel Prize in Physiology or Medicine 1929.
"for his discovery of the growth-stimulating vitamins"


Sir Frederick Gowland Hopkins (1861 - 1947) received the Nobel Prize in Physiology or Medicine for his seminal contributions to the discovery of vitamins. Hopkins identified essential components in milk that were absolutely required for growth and development in rats. Only a few drops of milk per day were sufficient.

The essential vitamins in milk can be separated into two different components. The lipid-soluble component consists of vitamins A and D [Monday's Molecule #78].

Hopkins is often credited with being the discoverer of vitamins but he disclaims this honor, pointing out in his Nobel Lecture that essential nutrients had been recognized by many others before him. He shared the Nobel Prize with Christiaan Eijkman. Altogether, there have been seven Nobel Prizes awarded for work on vitamins.

Hopkins became Professor of Biochemistry at Cambridge University in 1914. I think he was the very first Professor of Biochemistry at Cambridge.

The presentation speech was delivered by Professor G. Liljestrand, member of the Staff of Professors of the Royal Caroline Institute, on December 10, 1929

THEME:
Nobel Laureates
Your Majesty, Your Royal Highnesses, Ladies and Gentlemen.

That the fruits of civilization are not solely beneficial is shown by, inter alia, the history of the art of medicine. Not a few illnesses and diseases follow close on the heels of, and are more or less directly caused by, civilization. This is the case with the widespread disease beriberi, first described more than 1,300 years ago from that ancient seat of civilization, China. In modern times, however, it was not until towards the end of the 17th and the beginning of the 18th century that the disease attracted more general attention. Subsequently it has, on different occasions and with varying degrees of violence, made its appearance in all five continents, but more particularly its haunts have been in Eastern and South-Eastern Asia. At times the disease has been a serious scourge there. Thus in 1871 and 1879, Tokio was visited by widespread epidemics, and during the Russo-Japanese War it is said that not less than one-sixth of the Japanese army was struck down.

Beriberi shows itself in paralysis accompanied by disturbances in the sensibility and atrophy of the muscles, besides symptoms from the heart and blood vessels, inter alia, tiredness and oedema. Decided lesions have been shown in the peripheral nerves which seem to explain the manifestations of the disease. Mortality has varied considerably, from one or two per cent to 80 per cent in certain epidemics.

A number of circumstances indicated a connection between food and beriberi: for example, it was suggested that the cause might be traced to bad rice or insufficiency in the food of proteins or fat.

The severe ravages of beriberi in the Dutch Indies led the Dutch Government to appoint a special commission to study the disease on the spot. At the time, bacteriology was in its hey-day, and it was then but natural that bacteria should be sought as the cause of the disease, and indeed it was thought that success had been attained. The researches were continued in Java by one of the commission's coadjutors, the Dutch doctor Christiaan Eijkman. As has so often been the case during the development of science, a chance observation proved to be of decisive importance. Eijkman observed a peculiar sickness among the hens belonging to the laboratory. They were attacked by an upward-moving paralysis, they began to walk unsteadily, found difficulty in perching, and later lay down on their sides. The issue of the disease was fatal unless they were specially treated. It has been said that the secret of success is to be prepared for one's opportunity when it presents itself, and indubitably Eijkman was prepared in an eminent degree. With his attention focussed on beriberi, he immediately found a striking similarity between that disease and the sickness that had attacked the hens. He also observed changes in numerous nerves similar to those met with in the case of beriberi. In common with beriberi, this ailment of the hens was to be described as a polyneuritis. In vain, however, did Eijkman try to establish micro-organisms as the cause of the disease.

On the other hand, he succeeded in establishing the fact that the condition of the hens was connected with a change in their food, in that for some time before they were attacked they had been given boiled polished rice instead of the usual raw husked rice. Direct experiments proved incontestably that the polyneuritis of the hens was caused by the consumption of rice that by so-called «polishing» had been deprived of the outer husk. Eijkman found that the same disease presented itself when the hens were fed exclusively on a number of other starch-rich products, such as sago and tapioca. He also proved that the disease could be checked by the addition to the food of rice bran, that is to say, the parts of the rice that had been removed by polishing, and he found that the protective constituent of the bran was soluble in water and alcohol.

Eijkman's work led Vorderman to carry out investigations on prisoners in the Dutch Indies (where the prisoner's food was prepared in different ways according to the varying customs of the inhabitants), with a view to discovering whether beriberi in man was connected with the nature of the rice food they consumed. It proved that in the prisons where the inmates were fed on polished rice, beriberi was about 300 times as prevalent as in the prisons where unpolished rice was used.

When making investigations to explain the results reached, Eijkman considered that protein or salt hunger could not be the cause of the disease. But he indicated that the protective property of the rice bran might possibly be connected with the introduction of some particular protein or some special salt. At the time it might have been readily imagined that the polyneuritis in the hens and beriberi were due to some poison, and Eijkman set this up as a working hypothesis, though his attempts to establish the poison were in vain. In his view, however, such a poison was formed, but it was rendered innocuous by the protective substance in the bran. It was only Eijkman's successor in Java, Grijns, who made it clear that the substance in question was used directly in the body, and that our usual food, in addition to the previously known constituents, must contain certain other substances, if health is to be preserved. Funk introduced the designation vitamins for these substances, and since then the particular substance that serves as a protection against polyneuritis has been called the «antineuritic» vitamin.

It might have been expected that Eijkman's discovery would lead to an immediate and decided decline in beriberi - perhaps to the disappearance of the disease. But this was by no means the case, and not even in the Dutch Indies, where Eijkman and Grijns had worked, were the results particularly brilliant. The reasons for this were several: the reluctance of the inhabitants to substitute the less appetizing unpolished for polished rice, the opinion that polyneuritis in birds was not a similar condition to beriberi in man, and an inadequate appreciation of Eijkman's work. As a result of numerous experiments by different investigators on animals and human beings, who offered themselves for experimental work, it has gradually become clear that beriberi is a disease for the appearance of which lack of the vitamin found in rice bran - but also other circumstances - is of decisive importance. These experiences, in addition to successful experiments made in various places on the basis of Eijkman's observations, especially in British India, have gradually led to a general adoption of Eijkman's views. The successful attempts to combat beriberi which are now proceeding are the fruits of Eijkman's labours.

It was the analysis of the nature of the food used in cases of polyneuritis in hens that led Eijkman to his discovery. As a rule, analysis and synthesis complete each other, and indeed the employment of both these avenues of approach has been of decisive importance also for the development of the science of vitamins.

Although a number of experiments carried out about 50 years ago supported the assumption that, if our food is to have its full value, it must contain something more than the long-known basic constituents - proteins, fat, carbohydrates, water, and salts - yet it is not until our own days that complete certainty has been reached. One line of development has been sketched above. But numerous investigations have also been carried out by different experimentors with a view to testing the value of foods composed exclusively of the above-mentioned constituents in pure form. Sometimes it has proved to be a matter of some difficulty to get young animals to grow on such foods. One explanation put forward for this was the monotony of the food, and another was that the excessive purity resulted in the absence of certain substances giving the food taste which are necessary for appetite, and which must be present if the food is to be taken in sufficient amount. From other quarters, however, it was reported that even from the pure constituents, a food had been successfully produced which led to growth in the young organism.

When Hopkins joined the numbers of those who were trying to find a solution to this problem, he had the advantage of a far-reaching experience within similar fields of research, for he had done a great deal of detailed work on the presentation in pure form of certain proteins, and in connection therewith he had discovered the amino acid tryptophane as an element in certain proteins. As early as 1906 he had carried out careful feeding experiments on mice with different proteins, and by means of regular weighings it was observed whether the food was sufficient or not. It appeared from these experiments that the animal organism cannot itself build up tryptophane - proteins which do not contain it are not sufficient for the needs of the body. The simple methods employed by Hopkins came to play an important role later on.

When Hopkins continued his experiments, he fed young rats on a basic diet which, in addition to the necessary salts, contained a carefully purified mixture of lard, starch, and casein, i.e. the protein that is most abundantly found in milk. After some time the animals ceased to grow, which showed the insufficiency of this basic food in itself. By various experiments, however, Hopkins demonstrated that it was only necessary to add a very small daily amount of milk - two to three cubic centimeters for each animal - for growth to recommence. This amount of milk only corresponded to one or two per cent of the energy-content of the food, so that in this respect the addition of milk was insignificant. It was indeed found that incompletely purified casein, e.g. the ordinary casein of commerce, owing to the slight quantities of active substances present, was sufficient, with the other basic food, to maintain growth, even though it was considerably delayed. It was evident, as Hopkins was able to show more explicitly, that here was to some extent the explanation of the older and conflicting results.

Hopkins showed that there was a sufficiency of food consumed without the added milk, but it could be fully utilized by the body only when the growth-promoting influence of the milk was present. This effect was found not to be connected with any of the known constituent parts of milk. It was found also with yeast and the green parts of plants.

Hopkins communicated certain of his main results - but in an extremely brief form - as early as in 1906, and he returned to the subject in 1909 in a series of lectures, but it was not until three years later that his work was published in its entirety. By then Stepp had given accounts of experiments which, though they certainly seem less capable of one definite interpretation than those of Hopkins, yet point in the same direction, and the ground was also in other respects prepared, so that Hopkins' work was a great incentive to continued experiments in the young science of vitamins. Chiefly by American investigations it was shown that there are at least two vitamins necessary for growth, one soluble in fat, the other in water. It is still an open question whether the latter is identical with the antineuritic vitamin.

Just as at one time the newly acquired knowledge of bacteria as causes of illness opened the door to an entirely new province of research of extraordinary importance, so now the discovery of vitamins - even though to a lesser degree - has opened up new vistas to medicine, and we have advanced nearer to the understanding of numerous obscure maladies. Under the influence of Eijkman's discovery, Holst, with Frölich, exposed the nature and character of scurvy. Above all by the efforts of Hopkins' pupil Mellanby, it was found that rachitis was an illness due to lack of certain substances, and others have shown similar conditions for a large number of other maladies, the last one being pellagra, the similarity in principle of which to beriberi was already indicated by Eijkman in his classic work.

At the same time, extensive and important contributions have been made to the question of the nature of the physiological processes which are affected by vitamins.

Thus the discovery of vitamins, which is this year rewarded with the Nobel Prize, implies an advance of extraordinary significance, but there is still much of importance to be discovered that can at present be but dimly discerned or suspected.

Your Excellency, Baron Sweerts de Landas Wyborgh, Sir Frederick Gowland Hopkins. Many years have passed, since Eijkman found the antineuritic principle in food, but the great importance of this work has been appreciated but slowly. Today, however, the outstanding significance of the discovery is universally acknowledged not only for our understanding and our attempt to combat beriberi, but also because it has indicated a way of investigating and controlling many other deficiency diseases.

You, Sir Frederick, have demonstrated the physiological necessity of the vitamins for normal metabolism and growth, thus very considerably extending our knowledge of the importance of vitamins for life processes as a whole.

The discoveries of the antineuritic and the growth-promoting vitamins, for which the Caroline Institute has awarded the Nobel Prize in Physiology or Medicine this year, are foundation stones of the science of vitamins. Great as has been the progress in this field, yet we may still hope to reap rich harvests in the future.

On behalf of the Caroline Institute I express its hearty congratulations to the prizemen, and I beg Your Excellency to convey to your famous countryman its felicitations. With these words I have the great honour of asking you to accept the Nobel Prize for Physiology or Medicine from the hands of His Majesty the King.


[Photo Credit: Wikipedia]

Urban Cowboys

 
Here's a photo of Gord [Gordon Moran] and Rach about to descend into the Grand Canyon. Cute hats, eh?


The mules turned out to be stubborn and uncooperative. For a picture of what Gordon looked like when he was like that much younger, see here.


Tuesday, July 01, 2008

Good Science Writers: David Raup

 
David M. Raup is Avery Distinguished Service Professor (emeritus) of Geophysical Sciences, Evolutionary Biology, and The Conceptual Foundations of Science at the University of Chicago. He retired in 1994.

One of Raup's major interests is extinction. He worked closely with John Sepkoski on patterns of extinction in the fossil record and especially mass extinctions. In the introduction to his 1991 book, Extinction: Bad Genes or Bad Luck, Stephen Jay Gould writes,
... no topic now commands more interest among paleontologists than extinction. The reasons are many, with a prominent root to the impact theory of mass dying. But the principle architect of this shift is my brilliant colleague David M. Raup. Dave may be more at home before a computer console than before a dusty drawer of fossils (and he gets his share of flack from traditionalists for this predilection), but he is the acknowledged master of quantitative approaches to the fossil record. He saw the power of the impact scenario right from the beginning, when most paleontologists were howling with rage or laughter, and refusing to consider the proposal seriously. He has made the most important discoveries and proposed the most interesting and outrageous hypotheses in the field, including the suggestion that mass extinctions may cycle with a frequency of 26 million years. He is also the perennial Peck's bad boy of paleontology—a hard act to maintain past the age of fifty (I am struggling with him), but truly the most sublime of all statuses in science. If Dave has any motto, it can only be: Think the unthinkable (and then make a mathematical model to show how it might work); take an outrageous idea with a limited sphere of validity and see if it might not be extendable to explain everything. This book is a wonderful exposition of this potentially valid iconoclasm.

Raup is not one of the featured authors in The Oxford Book of Modern Science Writing. This shouldn't be a big surprise since not only is Raup a paleontologist—not Richard Dawkins' favorite topic—but his main thesis is the randomness of evolution—also not one of Dawkins' favorite topics.

The following quotations are from Extinction: Bad Genes or Bad Luck.
I have taken the title of this book from a research article I published in Spain some years ago. I was concerned then with the failure of trilobites in the Paleozoic era. Starting about 570 million years ago, these complex, crab-like organisms dominated life on ocean bottoms—at least they dominated the fossil assemblages of that age. But through the 325 million years of the Paleozoic era, trilobites dwindled in numbers and variety, finally disappearing completely in the mass extinction that ended the era, about 245 million years ago.

My question in Spain is the one I still ask: Why? Did the trilobites do something wrong? Were they fundamentally inferior organisms? Were they stupid? Or did they just have the bad luck to be in the wrong place at the wrong time? The first alternative, bad genes, could be manifested by things like susceptibility to disease, lack of good sensory perception, or poor reproductive capacity. The second, bad luck, could be a freak catastrophe that eliminated all life in areas where tilobites happened to be living. The question is basically one of nature versus nurture. Is proneness to extinction an inherent property of a species—a weakness—or does it depend on vagaries of chance in a risk-ridden world?

Of course, the problem is more complex than I have presented it, just as the nature-nurture question in human behavior is complex. But in both situations, nature (Genetics) and nurture (environment) operate to some degree, and the challenge is to find out which process dominates and whether the imbalance varies in time and space. (pp. 5-6)
Raup is known for his "Field of Bullets" scenario. Imagine that individuals in various species are killed at random. If the kill rate is high enough (e.g. 75%) then many species will be wiped out merely by chance while others will survive because some individuals were not struck by bullets. By chance, some genera will disappear because all of its species were wiped out. Sometimes an entire family or class of organisms will go extinct under this scenario: not because they were unfit but just because of bad luck.

Raup also describes The Gamblers' Ruin. Eventually all gamblers will lose all their money as long as they keep playing. That's because their winnings fluctuate up and down by chance but, while there may not be an upper limit to the amount of money they can win, there's definitely a lower limit and once the gambler runs out of money they are finished (extinct).

By recognizing these possibilities, Raup was able to model the life history of species and compare it to what is observed in the fossil record.
In the first chapter, I commented that the title of this book was taken from a research article I had published on the extinction of trilobites. The case provides another example of taxonomic selectivity.

In the rocks of the Cambrian period (570-510 ma BP), somewhat more than six thousand species of trilobites have been found and named. This is three-quarters of the fossil species known in the Cambrian. By the end of the Paleozoic era, 325 million years later, all were gone. On the working assumption that speciation and extinction rates for trilobites were the same as for all other animals of the Paleozoic, my question was whether a group as large as the trilobites could have drifted to extinction by bad luck—as an affluent gambler can drift to bankruptcy, given enough time.

I used mathematical models ... to estimate the probability that the trilobites could have died out because of a chance excess of species extinctions over speciations. The result was a vanishingly small likelihood that chance was operating alone in the trilobite case. The working assumption that trilobites had inherent extinction and speciation rates equal to the Paleozoic average was clearly wrong. It followed that trilobites had (for some reason) either less capability for speciation or a higher risk of extinction. Testing for the latter possibility, one finds the extinction credible only if one assumes life spans of trilobite species 14-28 percent less than the Paleozoic average.

From this, I concluded that the trilobites were indeed doing something wrong. (or that other groups were doing something better). One vote for bad genes. (pp. 102-103)
The trilobites may be the exception to the rule. In other chapters, Raup documents the apparent randomness of extinction. He concludes,
Extinction is evidently a combination of bad genes and bad luck. Some species die out because they cannot cope in their normal habitat or because superior competitors or predators push them out. But, as is surely clear form this book, I feel that most species die out because they are unlucky. They die because they are subjected to biological or physical stresses not anticipated in their prior evolution and because time is not available for Darwinian natural selection to help them adapt.

Having just made an advocacy statement—bad luck not bad genes!—I hope the reader appreciates its uncertainties. Favoring bad luck over bad genes is my best guess. It is shared by many of my colleagues even though a majority of paleontologists and biologists still subscribe to the more Darwinian view of extinction, that of a constructive force favoring the most fit species.

Is extinction through bad luck a challenge to Darwin's natural selection? No. Natural selection remains the only viable, naturalistic explanation we have for sophisticated adaptations like eyes and wings. We would not be here without natural selection. Extinction by bad luck merely adds another element to the evolutionary process, operating at the level of species, families, and classes, rather than the level of local breeding populations of single species. Thus, Darwinism is alive and well, but, I submit, it cannot have operated by itself to produce the diversity of life today.
I don't know why Raup's ideas are not more widely recognized and accepted. But it's not because he's a bad writer. His book is an example of how one can advocate a particular position while still giving other points of view their proper due. It's the hallmark of a good science writer.


Who Was More Important: Lincoln or Darwin?

 
This week's issue of Newsweek has an article by Malcolm Jones comparing the influence of Charles Darwin, the greatest scientist who ever lived, and an American politician named Abraham Lincoln. Why, you might ask, would anyone make such a comparison? It's because they were both born on February 12th, 1809.

Now, you might think this was a slam-dunk in favor of Darwin but that would be foolish. Remember that this is an American magazine. In America, Lincoln is responsible for abolishing slavery—conveniently ignoring the fact that slavery had already been illegal in the British Empire for almost thirty years. The Slavery Abolition Act was passed in 1833 and gave all slaves their freedom.

The answer is ... Lincoln!!! [Who Was More Important: Lincoln or Darwin?].
Lincoln and Darwin were both revolutionaries, in the sense that both men upended realities that prevailed when they were born. They seem—and sound—modern to us, because the world they left behind them is more or less the one we still live in. So, considering the joint magnitude of their contributions—and the coincidence of their conjoined birthdays—it is hard not to wonder: who was the greater man? It's an apples-and-oranges—or Superman-vs.-Santa—comparison. But if you limit the question to influence, it bears pondering, all the more if you turn the question around and ask, what might have happened if one of these men had not been born? Very quickly the balance tips in Lincoln's favor. As much of a bombshell as Darwin detonated, and as great as his book on evolution is (E. O. Wilson calls it "the greatest scientific book of all time"), it does no harm to remember that he hurried to publish "The Origin of Species" because he thought he was about to be scooped by his fellow naturalist Alfred Russel Wallace, who had independently come up with much the same idea of evolution through natural selection. In other words, there was a certain inevitability to Darwin's theory. Ideas about evolution surfaced throughout the first part of the 19th century, and while none of them was as cogent as Darwin's—until Wallace came along—it was not as though he was the only man who had the idea.

Lincoln, in contrast, is sui generis. Take him out of the picture, and there is no telling what might have happened to the country. True, his election to the presidency did provoke secession and, in turn, the war itself, but that war seems inevitable—not a question of if but when. Once in office, he becomes the indispensable man. As James McPherson demonstrates so well in the forthcoming "Tried by War: Abraham Lincoln as Commander in Chief," Lincoln's prosecution of the war was crucial to the North's success—before Grant came to the rescue, Lincoln was his own best general. Certainly we know what happened once he was assassinated: Reconstruction was administered punitively and then abandoned, leaving the issue of racial equality to dangle for another century. But here again, what Lincoln said and wrote matters as much as what he did. He framed the conflict in language that united the North—and inspires us still. If anything, with the passage of time, he only looms larger—more impressive, and also more mysterious. Other presidents, even the great ones, submit to analysis. Lincoln forever remains just beyond our grasp—though not for want of trying: it has been estimated that more books have been written about him than any other human being except Jesus.

If Darwin were not so irreplaceable as Lincoln, that should not gainsay his accomplishment. No one could have formulated his theory any more elegantly—or anguished more over its implications. Like Lincoln, Darwin was brave. He risked his health and his reputation to advance the idea that we are not over nature but a part of it. Lincoln prosecuted a war—and became its ultimate casualty—to ensure that no man should have dominion over another. Their identical birthdays afford us a superb opportunity to observe these men in the shared context of their time—how each was shaped by his circumstances, how each reacted to the beliefs that steered the world into which he was born and ultimately how each reshaped his corner of that world and left it irrevocably changed.

Answer: Lincoln
In fairness, if you only consider the United States of America, then the answer might be correct. Darwin's ideas do not have much influence there.

The comments on RichardDawkins.net are fun to read.


[Hat Tip: RichardDawkins.net]

Understanding Intelligent Design

 
Dembski's latest book Understanding Intelligent Design is now on sale. Here's what Dembski has to say about it on his blog [Understanding Intelligent Design — now available at Amazon.com!].1.
The book is geared at Christian young people (junior high and high schoolers) as well as for Church groups (e.g., Sunday Schools) to help get out the word about ID — specifically WHAT IS IT? WHY IS IT IMPORTANT? and WHAT YOU CAN DO ABOUT IT?

I was particularly concerned in writing the book to inoculate young people not only against the atheistic poison of Dawkins and Co. but also against the theological and scientific confusions of theistic evolutionists (like Ken Miller and Francis Collins). If this book does its job, both these camps will lose much of their traction with young people.
In case that's not enough to convince you to buy the book, Dembski includes the endorsements in his posting. Here's the one that will certainly make you sit up and take notice. With an endorsement like this you will know exactly how much credibility to assign to Understanding Intelligent Design.
“In my book Godless, I showed that Darwinism is the hoax of the century and, consequently, the core of the religion of liberalism. Like John the Baptist, Darwin foretold one of the key tenets of the left’s worldview: that humans are accidental descendants of earthworms, not the unique creations of an all-powerful God. Liberals respond to critics of their religion like Cotton Mather to Salem’s “witches.” With this book, two more witches present themselves for burning: Sean McDowell, whose gift is communicating with young people, and Bill Dembski, often called the Isaac Newton of Intelligent Design. I think Dembski is more like the Dick Butkus of Intelligent Design. His record for tackling Darwiniacs is unmatched. This book gives young people all the ammo they need to take on Darwinism and understand the only viable scientific alternative to Darwinism: Intelligent Design. Every high school student in America needs a copy of Understanding Intelligent Design.”

–Ann Coulter, BESTSELLING author of Godless: The Church of Liberalism


1. Some of my colleagues won't link to creationist web sites. I disagree with that policy. I think you should visit those sites often. They are the best possible advertisement against Intelligent Design.

Happy Canada Day

 


HAPPY

CANADA

DAY


Canada's official birthday is today. Lot's of people, including me, took yesterday off as well, making it a four-day weekend. Canada is 141 years old.

Here's a photograph of Canada's Fathers of Confederation (there were no mothers) at the Quebec Conference in 1864. I doubt that the average Canadian could name even one of these men. Try it without peeking at the website. Did you get more than five?




Monday's Molecule #78

 
Today is Tuesday so, once again, it's time for Monday's Molecule.1

This time there are two molecules and you have to get them both right in order to win. We'll need complete and accurate common names and IUPAC names. The two molecules have something in common, they belong to the same class of compounds. Can you guess what class it is?

As always, there's a connection between today's molecule and a Nobel Prize. The prize was awarded for being the first scientist to recognize that these molecules exist in nature and play an important role in biology. The structure of the molecules was not known when the Nobel Prize was awarded.

The first person to correctly identify the molecules and name the Nobel Laureate(s), wins a free lunch at the Faculty Club. Previous winners are ineligible for one month from the time they first collected the prize. There are four ineligible candidates for this week's reward. You know who you are.

THEME:

Nobel Laureates
Send your guess to Sandwalk (sandwalk (at) bioinfo.med.utoronto.ca) and I'll pick the first email message that correctly identifies the molecule and names the Nobel Laureate(s). Note that I'm not going to repeat Nobel Laureate(s) so you might want to check the list of previous Sandwalk postings by clicking on the link in the theme box.

Correct responses will be posted tomorrow. I may select multiple winners if several people get it right.

Comments will be blocked for 24 hours. Comments are now open.

UPDATE: This week's winner is Neel Patel. Here's his answer ..
Both molecules are fat-soluble vitamins.

The first molecule is Vitamin D3, or cholecalciferol. The IUPAC name is (3â,5Z,7E)-9,10-secocholesta-5,7,10(19)-trien-3-ol.

The second is Vitamin A, or retinol. The IUPAC name is (2E,4E,6E,8E) -3,7-dimethyl-9- (2,6,6-trimethylcyclohex-1-enyl) -nona-2,4,6,8-tetraen-1-ol

The Nobel Prize in Physiology or Medicine in 1929 pertinent to the above two molecules was awarded to Sir Frederick Gowland Hopkins, who was the first to propose the existence of vitamins, which he termed "accessory factors".


1. I took a day off from posting, just because I was lazy and it was a holiday.

Saturday, June 28, 2008

Good Science Writers: Helena Curtis

 
Helena Curtis is another science writer who didn't make it into The Oxford Book of Modern Science Writing. She died in 2005. One of many obituaries appeared in The villager [Helena Curtis, 81, wrote ‘elegant’ science textbooks].
Helena Curtis, a noted science writer and college biology textbook author, died on Feb. 11 at the age of 81. She was a resident of Sag Harbor and Greenwich Village.

Her first book, “The Viruses,” published in 1965 by Natural History Press, was followed in 1968 by “The Marvelous Animals.” In 1966, she was signed to a contract for a college biology textbook by Worth Publishers. The idea of a textbook written not by an academic, but by a professional science writer, in consultation with biology experts, was at that time revolutionary and greeted with skepticism. However, when Curtis’s “Biology” was published in 1968, it received a laudatory review in Scientific American by Nobel Laureate Salvador Luria. Through five editions in English it has sold 1.3 million copies. A shorter book, “Invitation to Biology,” has sold 600,000 copies. Both books have enjoyed success in Spanish and Italian editions, with more than 1 million of the books sold in Italian. On the later editions of both books, she was joined by N. Sue Barnes as co-author. Curtis also co-authored “Biology of Plants.”

Curtis’s books and her articles for encyclopedias, journals and magazines were praised for their scientific accuracy, elegant writing and wit. In 1988, Professor John O. Corliss of the University of Maryland said, with regard to the fifth edition of “Biology”: “The writing is about the closest to poetry that a scientific textbook can ever hope to get. It is thoroughly enjoyable, stimulating, imaginative, yet beautifully factual.”

The passage I've chosen is from her biology book. It's the opening paragraphs of Chapter 1. Her phrase "You and I are flesh and blood, but we are also stardust" is one of the most widely quoted sentences ever to come from a biology textbook.
Our universe began, according to current theory, with an explosion that filled all space, with every particle of matter hurled away from every other particle. The temperature at the time of the explosion—some 10 to 20 billion years ago—was about 100,000000000 degrees Celsius (1011 °C). At this temperature, not even atoms could hold together; all matter was in the form of subatomic, elementary particles. Moving at enormous velocities, even those particles had fleeting lives. Colliding with great force, they annihilated one another, creating new particles and releasing great energy.

As the universe cooled, two types of stable particles, previously present only in relatively small amounts, began to assemble. (By this time, several hundred thousand years after the "big bang" is believed to have taken place, the temperature had dropped to a mere 2500°C, about the temperature of white-hot wire in an incandescent light bulb.) These particles—protons and neutrons—are very heavy as subatomic particles go. Held together by forces that are still incompletely understood, they formed the central cores, or nuclei, of atoms. These nuclei, with their positively charged protons, attracted small, light, negatively charged particles—electrons—which moved rapidly around them. Thus, atoms came into being.

It is from these atoms—blown apart, formed, and re-formed over the course of several billion years—that all the stars and planets of our universe are formed, including our particular star and planet. And it is from the atoms present on this planet that living systems assembled themselves and evolved. Each atom in our own bodies had its origin in that enormous explosion 10 to 20 billion years ago. You and I are flesh and blood, but we are also stardust.

This text begins where life begins, with the atom. At first, the universe aside, it might appear that lifeless atoms have little to do with biology. Bear with us, however. A closer look reveals that the activities we associate with being alive depend on combinations and exchanges between atoms, and the force that binds the electron to the atomic nucleus stores the energy that powers living systems.


Darwinism at the ROM

 
Yesterday I attended a symposium on evolution at the Royal Ontario Museum [Darwin Symposium at the ROM]. The emphasis was on Charles Darwin, in line with the Darwin exhibit that is currently running at the ROM.

What I was expecting was a series of lectures that explain how Darwin fits into modern ideas of evolutionary biology. What I got was an adaptationist lovefest.

This was a free public symposium. By the time it started every seat in the auditorium was full and people were standing at the back. There were about 320 people of all ages and all walks of life. I sat beside a high school teacher and talked to retirees from the suburbs.

The first speaker was Michael Ruse. The original title of his talk was Has Darwinism Expired? but he modified it slightly to Is Darwin's Theory Past Its "Sell By" Date. His opening remarks were promising because he mentioned Stephen Jay Gould and Gould's criticism of Darwinism. He said that this was a distorted picture of evolution. It was downhill from that point on.

Ruse never explained why modern evolutionary theory differs from Darwin's evolution by natural selection. Instead he spent close to an hour going over examples of "evolution by natural selection." Most of his examples were, indeed, evidence of evolution but they were not necessarily evidence of evolution by natural selection. It's clear that Micheal Ruse does not distinguish between "evolution" and "natural selection." Evidence for evolution is treated as evidence for natural selection.

By the time he finished, the audience was completely unaware of random genetic drift, or any other mechanism of evolution. Ruse never explained why anyone would even bother to ask the question he asks in the title of his talk. According to Ruse, Darwinism is still the dominant paradigm in evolutionary biology. When examining characteristics of organisms biologists always ask "What is it for?", according to Michale Ruse. The answer will be explained by natural selection. This is the adaptationist fallacy. The correct question should be "Is this "for" anything?"

I know that Ruse is more of an adaptationist than a pluralist. I know that he favors Richard Dawkins and Daniel Dennett over Stephen Jay Gould and the pluralists. That's not the problem. What bothers me most is that when giving a public lecture Ruse does not even present the other side of the issue. What would it have cost him to mention that there are many evolutionary biologists who do not think of themselves as Darwinists? Why couldn't he explain that many of us think random genetic drift—and not natural selection—is the dominant mechanism of evolution? It doesn't diminish the importance of natural selection and adaptation. It doesn't diminish the contribution of Charles Darwin who still remains the greatest scientist who ever lived.

The second talk was by Spencer Barrett of the Department of Ecology & Evolutionary Biology here at the university of Toronto. Spencer Barrett was recently appointed to the rank of University Professor, our highest rank, in recognition of his work on evolution in flowering plants.

The title of his talk was A Darwinian Perspective on the Evolution of Plant Sexual Diversity and that's an accurate reflection of its content. Spencer Barrett is an adaptationist but in terms of his research he's a very successful example of this wordview. He chooses examples from plant evolution that almost certainly are adaptive and can be explained by natural selection. When faced with a strange example of plant sexual organs, Barrett begins by asking "What is the adaptive significance?"

After lunch we were treated to a lecture by Peter and Rosemary Grant on the evolution of Darwin's Finches. Most of you know the story. The Grants have spent 30 years collecting data on finches in the Galapagos. Everything about the evolution of Darwin's finches is explained by natural selection, especially changes in beak size. It has become the dominant example of evolution by natural selection.

The last lecture was delivered by Allan Baker of the Royal Ontario Museum. his title was Modern Darwinism: Natural Selection and Molecular Evolution. Baker works on bird evolution at the molecular level. He is trying to sort out the complicated, and controversial, relationship of bird clades. Baker pointed out that there are many conflicting data sets in the field and he explained how the use of signature sequences—in his case retrotransposon insertions—can be helpful. He noted in passing that he disagrees with the recent Science paper and cautions that bird evolution is still very much up in the air.

The irony here is that Baker was not studying "Darwinian" evolution at all. In spite of his title, it's extremely unlikely that the changes he looks at are due to natural selection. This was another missed opportunity, in my opinion. Baker could have explained to this public audience that molecular evolution is not Darwinian. It is an example of random genetic drift, which, incidentally, is why there's a molecular clock.

In talking to the lecturers afterward, I tried to find out how they thought about evolution. Baker, is well aware of the importance of random genetic drift. Barrett does not agree with me when I say that random genetic drift is the dominant mechanism of evolution at the molecular level and he does not agree that drift plays a role in speciation. Professor Barrett is one of the lecturers in our first year biology course on ecology and evolution. I've pointed out previously that in my second year course the students do not understand or appreciate random genetic drift and they tell me that it is barely mentioned in first year [Freedom in the Classroom]. I really enjoyed talking to Spencer Barrett and I hope we can continue the debate at another time.

The Grants claim that their evidence for natural selection is strong enough to rule out random genetic drift during the years when most of the finch population dies of starvation. The fluctuations in between could be due to drift.

Further reading ...

What Is Darwinism?
A Confused Philosopher
Darwin and Design by Michael Ruse
Why I'm Not a Darwinist
Evolution by Accident
Random Genetic Drift
Visible Mutations and Evolution by Natural Selection
Adaptationomics
Dennett on Adaptationism
The Evolution Poll of Sandwalk Readers


Friday, June 27, 2008

The Globe and Mail Reviews "Expelled"

 
So far, all of the Canadian reviews of Expelled have been good (i.e., they pan the movie). Some are more creative than others. Liam Lacy's review in the Globe and Mail is one of the best. It's set in the form of ten biblical verses [Expelled: No Intelligence Allowed]. The last verse is,
10. Then the Lord looked upon Ben Stein's work and declared: “Though I am a loving God, quite frankly, Ben, this film is an appallingly unscrupulous example of hack propaganda and it sucketh mightily. What's more, I didn't laugh once.”
The rating is "0." Denyse is going to be so disappointed in her journalist friends.


Mars to Sequence Cocoa Genome

 
Jonathan Eisen is excited because the Mars company is planning to sequence the cocoa genome [Combining two of my favorite things - chocolate and genomes]. See why this turns him on and why it isn't an example of science by press release.

The original press report is in the Washington Post [Unwrapping the Chocolate Genome]. The relevant point is the following ...
Mars plans to make the research results free and accessible through the Public Intellectual Property Resource for Agriculture, a group that supports agricultural innovation, as they become available. The intent is to prevent opportunists from patenting the plant's key genes.
Kudos to Mars if this turns out to be true.


In the interest of full disclosure I reveal that one of my children (Jane) works for Mars.

Thursday, June 26, 2008

Good Science Writers: David Suzuki

 
Of all the scientist writers who didn't make it into The Oxford Book of Modern Science Writing, David Suzuki surely counts as the most famous rejected Canadian.

David Takayoshi Suzuki earned his Ph.D. from the University of Chicago in 1961 and was a Professor at the University of British Columbia from 1963 until he retired in 2001. His research interests centered on the genetics of Drosophila melanogaster.

Suzuki founded the radio program Quirks and Quarks and serves as the host of the TV program On the Nature of Things. He has written 43 books and has received numerous awards for his contributions to science education. For the past three decades Suzuki has concentrated his efforts on environmental issues. Whether you agree with him or not, he is one of the world's best science writers.

The David Suzuki Foundation was set up, "to find ways for society to live in balance with the natural world that sustains us. Focusing on four program areas – oceans and sustainable fishing, climate change and clean energy, sustainability, and the Nature Challenge - the Foundation uses science and education to promote solutions that conserve nature and help achieve sustainability within a generation."

This essay on The Beauty of Wind Farms is copied from the New Scientist website. It was published on April 16, 2005.
OFF the coast of British Columbia in Canada is an island called Quadra, where I have a cabin that is as close to my heart as you can imagine. From my porch on a good day you can see clear across the waters of Georgia Strait to the snowy peaks of the rugged Coast Mountains. It is one of the most beautiful views I have seen. And I would gladly share it with a wind farm.

But sometimes it seems like I'm in the minority. All across Europe and North America, environmentalists are locking horns with the wind industry over the location of wind farms. In Alberta, one group is opposing a planned wind farm near Cypress Hills Provincial Park, claiming it would destroy views of the park and disturb some of the last remaining native prairie in the province. In the UK more than 100 national and local groups, led by some of the country's most prominent environmentalists, have argued that wind power is inefficient, destroys the ambience of the countryside and makes little difference to carbon emissions. And in the US, the Cape Wind Project, which would site 130 wind turbines off the coast of affluent Cape Cod, Massachusetts, has come under fire from famous liberals, including Senator Edward Kennedy and Walter Cronkite.

It is time for some perspective. With the growing urgency of climate change, we cannot have it both ways. We cannot shout from the rooftops about the dangers of global warming and then turn around and shout even louder about the "dangers" of windmills. Climate change is one of the greatest challenges humanity will face this century. It cannot be solved through good intentions. It will take a radical change in the way we produce and consume energy - another industrial revolution, this time for clean energy, conservation and efficiency.

We have undergone such transformations before and we can do it again. But first we must accept that all forms of energy have associated costs. Fossil fuels are limited in quantity and create vast amounts of pollution. Large-scale hydroelectric power floods valleys and destroys animal habitat. Nuclear power is terribly expensive and creates radioactive waste.

Wind power also has its downsides. It is highly visible and can kill birds. The fact is, though, that any man-made structure can kill birds - houses, radio towers, skyscrapers. In Toronto alone, it is estimated that 10,000 birds collide with the city's tallest buildings every year. Compared with this, the risk to birds from well-sited wind farms is very low.

Even at Altamont Pass in California, where 7000 turbines were erected on a migratory route, only 0.2 birds per turbine per year have been killed. Indeed, the real risk to birds comes not from windmills but from a changing climate, which threatens the very existence of bird species and their habitats. This is not to say that wind farms should be allowed to spring up anywhere. They should always be subject to environmental impact assessments. But a blanket "not in my backyard" approach is hypocritical and counterproductive.

Pursuing wind power as part of our move towards clean energy makes sense. It is the fastest-growing source of energy in the world - a $6 billion industry last year. Its cost has dropped dramatically over the past two decades because of larger turbines and greater knowledge of how to build, install and operate turbines more effectively. Prices will likely decrease further as the technology improves.

Are windmills ugly? I remember when Mostafa Tolba, executive director of the United Nations Environment Programme from 1976 to 1992, told me how when he was growing up in Egypt, smokestacks belching out smoke were considered signs of progress. Even as an adult concerned about pollution, it took him a long time to get over the instinctive pride he felt when he saw a tower pouring out clouds of smoke.

We see beauty through filters shaped by our values and beliefs. Some people think wind turbines are ugly. I think smokestacks, smog, acid rain, coal-fired power plants and climate change are ugly. I think windmills are beautiful. They harness the power of the wind to supply us with heat and light. They provide local jobs. They help clean our air and reduce climate change.

And if one day I look out from my cabin's porch and see a row of windmills spinning in the distance, I won't curse them. I will praise them. It will mean we are finally getting somewhere.
Today I was reminded of David Suzuki when John Pieret quoted from an article that Suzuki just published on cnews.canoe.ca [What a difference 50 years makes]. Here's an excerpt ...
I began speaking out on television in 1962 because I was shocked by the lack of understanding of science at a time when science as applied by industry, medicine, and the military was having such a profound impact on our lives. I felt we needed more scientific understanding if we were to make informed decisions about the forces shaping our lives. Today, thanks to computers and the Internet, and television, radio, and print media, we have access to more information than humanity has ever had. To my surprise, this access has not equipped us to make better decisions about such matters as climate change, peak oil, marine depletion, species extinction, and global pollution. That's largely because we now have access to so much information that we can find support for any prejudice or opinion.

Don't want to believe in evolution? No problem - you can find support for intelligent design and creationism in magazines, on websites, and in all kinds of books written by people with PhDs. Want to believe aliens came to Earth and abducted people? It's easy to find theories about how governments have covered up information on extraterrestrial aliens. Think human-induced climate change is junk science? Well, if you choose to read only certain national newspapers and magazines and listen only to certain popular commentators on television or radio, you'll never have to change your mind. And so it goes. The challenge today is that there is a huge volume of information out there, much of it biased or deliberately distorted. As I think about my grandson, his hopes and dreams and the immense issues my generation has bequeathed him, I realize what he and all young people need most are the tools of skepticism, critical thinking, the ability to assess the credibility of sources, and the humility to realize we all possess beliefs and values that must constantly be reexamined. With those tools, his generation will certainly leave a better world to its children and grandchildren 50 years from now.



[Photo Credit: Wikipedia: The copyright holder of this file, Joshua Sherurcij, allows anyone to use it for any purpose, provided that the copyright holder is properly attributed. Redistribution, derivative work, commercial use, and all other use is permitted.]

The Oxford Book of Modern Science Writing

 
The Oxford Book of Modern Science Writing, Richard Dawkins ed., Oxford University Press, Oxford, United Kingdom (2008)


I'd be lying if I said I read this book from cover to cover. Richard Dawkins has collected 83 short examples of science writing. Most of them are quite good, some of them are excellent, and some I didn't finish. The examples span the entire range of traditional science disciplines with a heavy emphasis on physics, astronomy, and biology. There are very few examples from chemistry or geology.

These are selections picked by Richard Dawkins and they strongly reflect his views of science and of good writing. One of the criteria for inclusion is "good writing by professional scientists, not excursions into science by professional writers" (p. xvii). There's nothing wrong with that, as long as Dawkins sticks to his guns.

Unfortunately, there are so many exceptions to the rule that one wonders why the rule was made up in the first place. We don't have anything by Carl Zimmer (a non-scientist), for example, but we do have examples from Matt Ridley who, while he has a Ph.D. in science has never been a professional scientist. Neither has Daniel Dennett. Rachel Carson worked as a biologist for a while but she was a full-time writer by the time she wrote most of her books. Roger Lewin has never been a professional scientist, as far as I know.

Perhaps Dawkins meant to restrict his authors to those who have earned an advanced degree in science regardless or whether they actually became working scientists. Perhaps that's what he means by "professional scientist." If that's what he means then, as he points out on page 171, Margaret Thatcher might qualify since she got her Master's degree in Chemistry and worked with with Dorothy Hodgkin as an undergraduate. Hodgkin is included. Thatcher isn't.

Dawkins has three other rules. First, all of the works were produced within the past 100 years. This is an excellent restriction, in my opinion. Second, the works must have been first published in English—no translations are allowed (with a few exceptions). Finally, no works by Richard Dawkins are included.

Dawkins introduces each author with a few paragraphs of background material that often includes personal anecdotes. This is where we learn that Dawkins and Gould, "enjoyed—or suffered—a kind of love/hate relationship." We also discover that Fred Hoyle wrote an article that serves as, "an example of the insight that a physical scientist can bring to biology," bearing in mind that it was written, "before Hoyle began the perverse campaign of his old age, against all aspects of Darwinism."1

Some of the choices are very pleasant surprises. I had never heard of James Jeans, the first author in the book. His entry is so interesting—and so in line with modern thought—that I can't resist a quotation. Keep in mind that this was written in 1930.
Into such a universe we have stumbled, if not exactly by mistake, at least as the result of what may properly described as an accident. The use of such a word need not imply any surprise that our earth exists, for accidents will happen, and if the universe goes on for long enough, every conceivable accident is likely to happen in time.
Many of Dawkins' choices have nothing to do with biology but, of those that do, most extol the virtues of design and natural selection. For example, there is a passage from Helena Cronin's The Ant and the Peacock that's as fine an example of science-related prose as can be found anywhere in the anthology. It is good writing but I don't it is good science. Dawkins does, and it's his book and his choice.

This brings me to an important point. In order to be included in any collection of good science writing the work has to be both good writing and good science.2 Both of these criteria are subjective so whether an author is included or not will depend very much on the point of view of the editor. In this case we learn almost as much about Richard Dawkins as we do about the authors he selects.

And the authors he omits. Of the three giants of population genetics, R.A. Fisher and J.B.S. Haldane get included but Sewell Wright isn't even named. There's nothing by Richard Lewontin, Niles Eldredge, Gabriel Dover or David Raup. Ken Miller, Francis Collins, and Simon Conway-Morris are missing as well. Daniel Dennett is there but not Michael Ruse. One gets the impression that a similar book edited by Stephen Jay Gould would look quite different.

Now don't get me wrong. There's nothing wrong with this. As far as I'm concerned "good" science writing includes scientific accuracy and Dawkins has every right to pick and choose those authors who get it right, in his opinion. However, I'd prefer that editors lay their cards on the table and admit openly that their selections are influenced by this bias.3

No book of this sort should be complete without Peter Medawar and this book is no exception. Medawar's famous wit is unequaled, and often unappreciated. I fear it is a lost art. Dawkins is such a fan of Medawar (as am I) that he includes five excerpts from his books and essays—more than any other science writer.

Let me close with a quotation from Peter Medawar's essay on Science and Literature where Medawar is discussing a modern trend among philosophers and scientists to write very complicated prose,
Let me end this section with a declaration of my own. In all territories of thought which science or philosophy can lay claim to, including those upon which literature also has a proper claim, no one who has something original or important to say will willingly run the risk of being misunderstood: people who write obscurely are either unskilled in writing or up to some mischief. The writers I am speaking of are, however, in a purely literary sense, extremely skilled.

1. In contrast to Dawkins' praise, I found the passage from Hoyle to be almost incomprehensible. It is not good science writing, in my opinion, and it certainly isn't "insightful."

2. There are exceptions. Dawkins included a passage from R.A. Fisher's book The Genetical Theory of Natural Selection even though he (Dawkins) recognizes that it may not be an example of good writing.

3. I'm going to post some examples of my own biases with respect to good science writing, concentrating almost exclusively on those writers that don't appear in The Oxford Book of Modern Science Writing.

Wednesday, June 25, 2008

Nobel Laureate: Susumu Tonegawa

 

The Nobel Prize in Physiology or Medicine 1987.
"for his discovery of the genetic principle for generation of antibody diversity"


Susumu Tonegawa (1939 - ) received the Nobel Prize in Physiology or Medicine for working out the mechanism of generating antibody diversity. This was one of the fundamental problems in immunology—and, indeed, all of biology. How do antibodies recognize so many different antigens?

We now know the answer thanks to Tonegawa and his coworkers. The genes for antibody proteins are constructed in antibody-producing cells by recombining bits of DNA from several different locations. Millions of different permutations can be constructed to create a random library of antibody molecules. The chance that one of these randomly constructed antibody molecules will recognize a new antigen, such as virus, is very high.

This is one of the most significant Nobel Prizes of the 2oth century. Tonegawa's discovery deserves a lot more attention that it normally gets.

The presentation speech was delivered (in Swedish) by Professor Hans Wigzell of the Karolinska Institute.

THEME:
Nobel Laureates
Your Majesties, Your Royal Highnesses, Ladies and Gentlemen,

The defence of our body against infections is carried out by the immune system, a talented cellular society with a capacity to distinguish between self and non-self and with a memory capable of remembering a previous contact for decades. The system is managing this through the inbuilt capacity in a single human being to produce billions of different forms of protective molecules, antibodies. The Nobel Prize of this year is given for the elucidation of the unique capacity of the immune system to produce this enormous diversity of specific antibodies.

Susumu Tonegawa is the great molecular biologist in immunology. In a series of ingenious experiments carried out in the middle of the 1970's he solved the problem how our limited genetic material is capable of generating the diversity required to create protection against established as well as future disease provoking microorganisms. When Tonegawa did his experiments at the Basel Institute of Immunology in Switzerland other scientists had already generated a-considerable amount of knowledge regarding the features and functions of antibodies. But this knowledge had also led to uncertainty and even confusion. Antibodies are proteins and their structure is strictly ruled by genes, by the DNA in our chromosomes. When Tonegawa carried out his experiments it was commonly believed that each protein, each polypetide chain, was governed by its gene in a relation one to one. But at the same time calculations on the number of genes in the chromosomes in man determining proteins gave a number probably below one hundred thousand genes. They should suffice to all the proteins in the body, to the hemoglobin in the red blood cells, to the pigment in our eyes and so on. Only a minor part, maybe one percent, could probably be used for the creation of antibodies. Around one thousand genes being able to create billions of different forms of antibodies? The equation seemed impossible to solve.

Our antibodies are made up of two sorts of polypeptide chains, short and long ones. Tonegawa did first acquire a toolbox, filling it with the best precision tools there were of hybrid-DNA nature, developed new methods and started to study the actual construction of the genes determining the short chains of antibody molecules. He discovered something entirely new and revolutionary in genetics. On the chromosome where the gene for the short chain was expected to be located, there was not one single, but a string, of pearls of genes. One special gene resided at one position whereas two other sets of variable genes create two gene families, in all maybe around one hundred genes. When a cell should start to make antibodies - this was preceded by a gene-lottery.

One member of the largest gene family selected at random was cut out from the chromosome and moved close to a member of the second gene family, whereafter they created a functional gene for the short chain together with the solitary gene. Three and not one gene participate in the creation of the short chain of antibody molecules. Each member in one family can probably be linked to any one of the members of the second gene family, increasing variability by multiplication. The results showed beyond doubt that our body has the capacity to carry out advanced recombinant DNA processes. The intelligence of Nature can also be seen as the studies went on. The recombination of genes and their coupling together do not occur in exactly the correct manner. While such relative misfits should in other systems be bad, here they constituted yet another mechanism of increasing the diversity of antibodies. Experiments by Tonegawa as well as other scientists also revealed that the same genetic lottery principle did apply to the generation of the long chain although here the number of variants were even larger. Four different genes could be shown to create these chains together. The number of variant short chains should then be multiplied by the combinatorial possibilities of the heavy chain to give the variation at the antibody level, a fact which will also drastically enhance the diversity of antibodies.

The equation was in essence solved. A few hundred genes are used by the body in a new, revolutionary way and can thus generate billions of different antibodies. Through this genetic lottery the immune system is always prepared to react against known as well as unknown microorganisms. The economic usage of precious DNA is compensated by wasting more dispensable material. Every minute our body produces several millions of white blood cells - lymphocytes. Each one of these has undergone the hybrid-DNA procedure and is prepared with its own, unique antibodies. If not called upon to react they will rapidly die. If, however, they make contact with the fitting foreign structures they receive a reward, i.e., they are allowed to proliferate and live longer. After the great randomized gene lottery natural selection will pick the winners, thereby generating specific immunity, the cheapest and most efficient protection there is against infections.

Dr. Tonegawa,

On behalf of the Nobel Assembly of the Karolinska Institute I would like to congratulate you on your outstanding accomplishments and ask you to receive the Nobel Prize in Physiology or Medicine from the hands of His Majesty the King.



[Photo Credit: Nature]

[Figure credit: The figure showing immunoglobulin gene rearrangment is from carthage.org]