The Evolution of God

 
Robert Wright is a journalist known for founding Bloggingheads.tv. He has written several books, notably The Evolution of God, which was published this year.

His schtick is the compatibility of science and religion. According to him, accommodation will be achieved once believers come to accept natural selection and convert to some form of deism, and once atheists learn to accept that this kind of wishy-washy (not his terminology) religion is compatible with science.

I recently linked to a blogging heads discussion between Wright and Daniel Dennett in which I criticized both of them for misunderstanding evolution. Wright seems to have bought into the Dennett idea of natural selection being the only mechanism of evolution. Wright also believes that natural selection will inevitably lead to sentient beings with a sense of moral purpose.

If this is true then science has to accept the fact that God could have cooked the books so that creatures would eventually evolve to the point where they were willing to worship him and offer sacrifices. And they would do so in spite of the absence of scientific evidence for the existence of such a non-interventionist, deistic, God. All the stories about an interventionist God must be wrong. If you're a deist, there was no deluge, no chosen people, and no divine Jesus.

Under such a scenario, I often wonder how believers would know what kind of God to worship. How do you distinguish between a Satan and Gitche Manitou if the deistic god has gone to such great lengths to be hands off during the evolution of sentient beings?

Robert Wright's latest foray into this debate comes as an op-ed piece in yesterday's New York Times: Direction and Purpose in Evolution. He reiterates the point that both sides of the war between science and religion are wrong. He is a confirmed accommodationist.

There are atheists who go beyond declaring personal disbelief in God and insist that any form of god-talk, any notion of higher purpose, is incompatible with a scientific worldview. And there are religious believers who insist that evolution can't fully account for the creation of human beings.

I don't want to discuss that argument except to say, for the record, that I'm one of those who insist that's there's no evidence of purpose in the evolution of life. Any talk of there being a direction to evolution, where sentient beings are the ultimate goal, founders on a massive lack of evidence in support of such a notion.

However, I'm willing to accept that biological science is more or less compatible with the existence of a supernatural being who created life on Earth and then stepped back to let history play out according to the standard rules of physics and chemistry.

Where I differ from people like Wright and Dennett is that my version of evolution is not restricted to natural selection. In my view of evolution, accident and chance play important roles at both the macro- and micro levels. Mass extinctions are just one example at the macro- level and random genetic drift is the most important example at the micro- level.

Why is this important? It's important because it gets us away from "design" talk. Most believers are committed to talk of design and purpose because otherwise life has no meaning. If they accept evolution then they make science and religion compatible by evoking God as the cause of natural selection. In this accommodationist scenario, God achieves his purpose through the law of natural selection.

Some philosophers and evolutionary biologists also believe that evolution is an algorithmic process, relying (almost) exclusively on natural selection as the driving force. Some, like Daniel Dennett, use metaphors such as building skyscrapers in order to illustrate their view of purposeful evolution. By invoking purpose and design, these philosophers and evolutionary biologists lend support to those believers who also see evidence of design and purpose. Robert Wright is correct to point out that the two groups, atheistic adaptationists and deistic believers, are not that far apart.

I bring good news! These two warring groups have more in common than they realize. And, no, it isn't just that they're both wrong. It's that they're wrong for the same reason. Oddly, an underestimation of natural selection's creative power clouds the vision not just of the intensely religious but also of the militantly atheistic.

If both groups were to truly accept that power, the landscape might look different. Believers could scale back their conception of God's role in creation, and atheists could accept that some notions of "higher purpose" are compatible with scientific materialism. And the two might learn to get along.

This is a little confusing because many of the "militant atheists" he complains about are strong adaptationists who are only too willing to explain everything by natural selection. Those scientists clearly see design and purpose in evolution, but that doesn't make them accommodationists.

Robert Wright evokes evolutionary psychology in defense of accommodationism. Using the "moral law" example, he points out that natural selection can explain morality and believers have to accept this "fact." However, those same believers can take comfort in the idea that God planned this when he created natural selection in the first place, so the evolution of a "moral law" is consistent with belief in a deistic God.

Indeed, this dynamic of reciprocal altruism, as mediated by natural selection, seems to have inclined us toward belief in some fairly abstract principles, notably the idea that good deeds should be rewarded and bad deeds should be punished. This may seem like jarring news for C. S. Lewis fans, who had hoped that God was the one who wrote moral laws into the charter of the universe, after which he directly inserted awareness of them in the human lineage.

But they may not have to stray quite as far from that scenario as they fear. Maybe they can accept this evolutionary account, and be strict Darwinians, yet hang on to notions of divinely imparted moral purpose.

The first step toward this more modern theology is for them to bite the bullet and accept that God did his work remotely — that his role in the creative process ended when he unleashed the algorithm of natural selection (whether by dropping it into the primordial ooze or writing its eventual emergence into the initial conditions of the universe or whatever).

Of course, to say that God trusted natural selection to do the creative work assumes that natural selection, once in motion, would do it; that evolution would yield a species that in essential respects — in spiritually relevant respects, you might say — was like the human species. But this claim, though inherently speculative, turns out to be scientifically plausible.

Wright is mostly directing his arguments at theists in order to convince them that they can accept evolution without abandoning the concepts of a God-given morality and a life with meaning and purpose. He spends less time trying to convince atheistic scientists because he believes that his interpretation of the science is correct. His blogging head conversation with philosopher Daniel Dennett has convinced him that most scientists think this way.

For starters, there are plenty of evolutionary biologists who believe that evolution, given long enough, was likely to create a smart, articulate species — not our species, complete with five fingers, armpits and all the rest — but some social species with roughly our level of intelligence and linguistic complexity.

And what about the chances of a species with a moral sense? Well, a moral sense seems to emerge when you take a smart, articulate species and throw in reciprocal altruism. And evolution has proved creative enough to harness the logic of reciprocal altruism again and again.

This is the part I dispute. I don't believe that the evolution of some sort of sentient species was inevitable. And I don't believe there's a universal moral law that evolved due to natural selection. My version of evolution, involving copious amounts of chance and accident, just happened to produce sentient beings on this planet. I suspect that if we looked at a thousand planets with life we wouldn't see another example.

Furthermore, I think that our sense of proper morality is mostly cultural, not genetic. We didn't "evolve" a hard-wired guilty feeling whenever we treated people unfairly. After all, people in many cultures supported slavery and mistreatment of women for thousands of years without being consumed by the expression of their "guilt" genes. Most of what passes for morality is not due to genes (alleles) for reciprocal altruism. Instead, a great deal of "morality" is an epiphenomenon that follows naturally whenever you have intelligent beings living together in a society that has learned the advantages of co-operation.

Robert Wright's mistake is assuming that adaptationism is the general consensus in biology. His accommodationist argument fails if science doesn't recognize design and purpose as the key paradigms of evolution.

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Intelligent Design Creationists and Lateral Gene Transfer

 
Some of you might recall an article in Nature Physics published a few weeks ago [Collectivist Revolution in Evolution]. In that article, Mark Buchanan, a physicist, mentioned that biologists were questioning the tree of life.

Buchanan gets so many things wrong I hardly knew where to begin. So, when I blogged about it I just mentioned one thing [Lateral Gene Transfer and the Return of Lamarckian Evolution]. I concluded with ...

This kind of hyperbole is not helpful. Shame on Nature Physics for publishing it.

As expected, the creationists—intelligent and otherwise—were delighted with this latest challenge to evolution. I doesn't matter to them whether a physicist knows what he's talking about.

One of the "otherwises" is named Denyse O'Leary. She's happy to promote the idea that evolution¹ is being challenged. It's a special thrill for her to discover that biology is being questioned in a physics journal [The overthrow of Darwinism - in real life, forget the pop science media].

Denyse doesn't do any of the intellectual heavy lifting (surprise!). Instead she links to another Intelligent Design Creationist named David Tylor. Tylor is also mesmerized by the Nature Physics article. He blogged about it at: The collectivist challenge to Darwinism.

Here's part of what he said ...

Talk of unseating Darwinian evolution has not gone down well with some. Larry Moran quotes some of Buchanan's visionary words and declares: "This kind of hyperbole is not helpful. Shame on Nature Physics for publishing it." However, we could do with more substance in arguments against this essay. Darwinism is inherently reductionistic and it can devise ways of framing HGT to fit into its own mental models. But what it cannot easily do is adopt the holistic perspectives that are emerging everywhere. This is why some of us find a framework of design to be compelling. Design provides a coherent context for systems biology, for biomimetics, and for many other contemporary areas of research. Furthermore, although our understanding of HGT is imperfect and in its infancy, design thinking provides a warrant for inferring the origin of genes capable of being transferred, and for understanding the roles played by HGT in populations.

Where to begin?

Horizontal gene transfer (HGT, also known as Lateral Gene Transfer) has been studied for six decades. We have an excellent understanding of the mechanisms; namely, transformation, transduction, conjugation, fusion, and endosymbiosis. There's nothing new there.

"Darwinism" and "Darwinian evolution" are products of the nineteenth century. The only people who are stuck in that century are the creationists. Modern evolutionary biologists have been at the forefront of "holistic" approaches since the recognition that populations evolve, not individuals. For most biologists, this happened in the 1940s. To put this into perspective, that's at least sixty years ago, or 1% of the entire history of Earth!

I'm actually quite happy to promote the "unseating [of] Darwinian evolution" as anyone who reads Sandwalk will attest. David Taylor and Denyse O'Leary are completely incapable of recognizing that legitimate challenges to the old-fashioned way of thinking about evolution are now part of mainstream biology. In fairness, what can we expect from people who think that a 2500 year old book written in Hebrew, Aramaic, and Greek still contains relevant information about science?

"Design" fails to provide a coherent context for anything. I've yet to see anyone explain how and when God intervened to create modern life.

Finally, in case David Tylor is actually interested in learning about the science he criticizes, here's a list of recent postings on the topic. I'd be happy to debate him whenever he feels ready. I'd be happy to do it on The ID Update: News and Commentary Updates for the ID Community but that blog doesn't allow comments. Isn't that strange?

1. The Tree of Life
2. Perspectives on the Tree of Life: Ford Doolittle
3. Perspectives on the Tree of Life: Day One
4. Perspectives on the Tree of Life: Day Two
5. Perspectrives of the Tree of Life: Day Three
6. On the Origins of Eukaryotes

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1. She calls it "Darwinism," just like all the other IDiots.

Creationists Made Him Do It!

 
A reader¹ alerted me to a letter by Patrick J. Keeling in the latest issue of Science: Creationists Made Me Do It.

He tells a story about hearing creationists speak in his high school biology class. What was the effect of this indoctrination? ...

For at least one sulky teenager in the small town of Owen Sound, Ontario, it took a creationist to make him into an evolutionary biologist.

This is one of the reasons why exposing high school students to the IDiots should be encouraged, not banned. They are their own worst enemy.

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1. Thank-you Grace.

Anne Wojcicki's Politically Correct View of Race

 
Anne Wojcicki is the co-founder of "23andMe" a company that will analyze your DNA for a fee. She was recently interviewed and the results are posted on the New York Times website [Genetics Entrepreneur Anne Wojcicki Answers Your Questions].

One of the questions asked about "race." Here's her reply.

A lot of the difficulty in talking about race has been a lack of agreement on what “race” means. In the past, the idea of pure races also included an ordering of certain races as inherently superior to others. We reject this idea absolutely. However, that doesn’t mean that there are no genetic differences between populations of different ancestral origin. A few of our features use the genome-wide data of reference populations from around the world to trace the origin of pieces of an individual’s genome. Some customers have complex patterns depending on where their ancestors originated. These reference populations aren’t “races”; they’re representative samples of peoples who have lived in a single place for a very long time and have thus accumulated different sets of genetic variants over time.

John Hawks noticed this and blogged about it: Modern genomics and race. He said exactly what I was thinking ...

That's a tricky piece of wordcraft -- they're not 'races'; "they're representative samples of peoples who have lived in a single place for a very long time and have thus accumulated different sets of genetic variants over time."

Uhh....I'm thinking that's pretty much the definition of race in a lot of textbooks...

Most species are subdivided into races (also called subspecies, or demes).

Humans are not an exception. Races exist. Pretending that they don't isn't going to solve the problems of racism. It just makes you look stupid.

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The Evolution of Man Scientifically Disproved

 
When David Schuller came to visit me a couple weeks ago he brought me a special present. It was a book he found in a bookstore. Dated 1925, the title is, The Evolution of Man Scientifically Disproved. The author is the Rev. William A. Williams formerly the president of Franklin College. I thought it might be interesting to present one of his “disproofs” of evolution.

You may think it unfair to dredge up a defense of creationism based on a 84 year old book. It’s not unfair because I’m using the same standards that the creationists use when they talk about “Nebraska Man” and the Scopes trial, not to mention Charles Darwin and Ernst Haeckel. It’s clear that 1925 is “modern science” from their perspective.

Furthermore, the arguments of Rev. Williams aren’t any worse than the ones used in 2009! The title page makes it clear that this is the best that creationists have to offer.

Designed. (1) As an up-to-date text book, and a companion to all other text books on evolution; and

(2) As an antidote to books in libraries teaching evolution, infidelity and atheism; and

(3) As an aid to all students, parents, teachers, ministers, lawyers, doctors, and all other lovers of the truth.

Rev. Willimas begins with a discussion of the population of the world.

The population of the world, based upon the Berlin Census reports of 1922, was found to be 1,804,187,000. The human race must double itself 30.75 times to make this number. This result may be approximately ascertained by the following computation:—

At the beginning of the first period of doubling there would just be two human beings; the second, 4; the 8, eight; the fourth, 16; the tenth, 1024; the twentieth, 1,048,576, the thirtieth, 1,073,741,824; and the thirty-first, 2,147,483,648. In other words, if we raise two to the thirtieth power, we have 1,073,741,824; or to the thirty-first power, 2,147,483,648. Therefore, it is evident even to the school boy, that, to have the present population of the globe, the net population must be doubled more than thirty times, and less than thirty-one times. By logarithms, we find it to be 30.75 times. After all allowances are made for natural deaths, wars, catastrophes, and losses of all kinds, if the human race would double its numbers 30.75 times, we would have the present population of the globe.

Now, according to the chronology of Hales, based on the Septuagint text, 5077 years have elapsed since the flood, and 5177 years since the ancestors of man kind numbered only two, Noah and his wife. By dividing 517 7 by 30.75, we find it requires an average of 168.3 years for the human race to double its numbers, in order to make the present population. This is a reasonable average length of time.

Moreover, it is singularly confirmed by the number of Jews, or descendants of Jacob. According to Hales, 3850 years have passed since the marriage of Jacob. By the same method of calculation as above, the Jews, who according to the Jewish yearbook for 1922, number 15,393,815, must have doubled their numbers 23.8758 times, or once every 161.251 years. The whole human race, therefore, on an average has doubled its numbers every 168.3 years; and the Jews, every 161.251 years. What a marvelous agreement! We would not expect the figures to be exactly the same no more be greatly surprised if one period were twice the other. But their correspondence singularly corroborates the age of the human race and of the Jewish people, as gleaned from the word of God by the most proficient chronologists. If the human race is 2,000,000 years old, the period of doubling would be 65,040 years, or 402 times that of the Jews, which, of course, is unthinkable

While the period of doubling may vary slightly in different ages, yet there are few things so stable and certain as general average, where large numbers and many years are considered, as in the present case. No life insurance company, acting on general average statistics, ever failed on that account. The Jews and the whole human race have lived together the same thirty-eight centuries with very little intermarriage, and are affected by similar advantages and disadvantages, making the comparison remarkably fair.

Also the 25,000,000 descendants of Abraham must have doubled their numbers every 162.275 years, during the 3,988 years since the birth of his son Ishmael. These periods of doubling which tally so closely, 168.3 years for the whole race, 161.251 for the Jews, and 162.275 years for the descendants of Abraham, cannot be a mere coincidence, but are a demonstration against the great age of man required by evolution, and in favor of the 5,177 years since Noah. None of the other various chronologies would make any material difference in these calculations. The correspondence of these figures, 168.3, 161.251 and 162.275 is so remarkable that it must bring the conviction to every serious student at the flood destroyed mankind and Noah became the head of the race.

Now the evolutionists claim that the human race is 2,000,000 years old. There is no good reason for believing that, during all these years the developing dominant species would not increase as rapidly as Jews, or the human race in historic times, especially since the restraints of civilization and marriage did not exist. But let us generously suppose that these remote ancestors, beginning with one pair, doubled their numbers in 1612.51 years, one-tenth as rapidly as the Jews, or 1240 times in 2,000,000 years. If we raise 2 to the 1240th power, the result is 18,932,139,737,991 with 360 figures following. The population of the world, therefore, would have been 18,932,139,737,991 decillion, decillion, decillion, decillion, decillion, decillion, decillion, decillion, decillion, decillion, decillion, or 18,932,139,737,991 vigintillion, vigintillion, vigintillion, vigintillion, vigintillion/

Or, let us suppose that man, the dominant species originated from a single pair, only 100,000 years ago, the shortest period suggested by any evolutionists (and much too short for evolution) and that the population doubled in 1612.51 years, one-tenth the Jewish rate of net increase, a most generous estimate. The present population of the globe should be 4,660,210,253,138,204,300 or 2, 527,570,733 for every man, woman and child! In these calculations, we have made greater allowances than any self-respecting evolutionist could ask without blushing. And yet withal, it is as clear as the light of day that the ancestors of man could not possibly have lived 2,000,000 or 1,000,000 or 100,000 years ago, or even 10,000 years ago; for if the population had increased at the Jewish rate for 10,000 years, it would be more than two billion times as great as it is. that has ever been made, or ever can be made, much in excess of 5177 years, can possibly stand as the age of man. The evolutionist cannot sidestep this argument by a new guess. Q. E. D.

All these computations have been made upon the supposition that the human race sprang from one pair. If from many in the distant past, as the evolutionists assert, these bewildering figures must be enormously increased.

Yet we are gravely told that evolution is "science". It is the wildest guess ever made to support an impossible theory.

That their guesses cannot possibly be correct, is proven also by approaching the subject from another angle. If the human race is 2,000,000 years old, and must double its numbers 30.75 times to make the present population, it is plain that each period for doubling would be 65,040 years, since 2,000,000 ÷ 30.75 = 65,040. At that rate, there would be fewer than four Jews! If we suppose the race to have sprung from one pair 100,000 years ago, it would take 3252 years to double the population. At this rate, there would be five Jews!

Do we need any other demonstration that the evolution of man is an absurdity and an impossibility? If the evolutionists endeavor to show that man may have dissented from the brute, the population of the world conclusively shows that MAN CERTAINLY DID NOT DESCEND FROM THE BRUTE. If they ever succeed in showing that all species of animals may have been derived from one primordial germ, it is impossible that man so came. He was created as the Bible declares, by the Almighty Power of God.

The testimony of all the experts in the present Scopes trial in Tennessee (who escaped cross-examination) was to the effect that evolution was in harmony with some facts and therefore possibly true. The above mathematical calculations prove that the evolution of man certainly not true. They fail to make their case even if we grant their claims. These figures prove the Bible story, and scrap every guess of the great age and the brute origin of man. It will be observed at the above calculations point to the unity of the race in the days of Noah, 5177 years ago, rather than in the days of Adam 7333 years ago, according to Hale's chronology. If the race increased at the Jewish rate, not over 16,384 perished by the Flood, fewer then by many a modern catastrophe. This most merciful providence of God started the race anew with a righteous head.

Now, if there had been no flood to destroy the human race, then the descendants of Adam, in the 7333 years, would have been 16,384 times the 1,804,187,000, or 29,559,799,808,000; or computed the Jewish rate of net increase for 7333 years since Adam, the population would have been still greater, or 35,184,372,088,832. These calculations are in perfect accord with the Scripture story of the special creation of man, and the destruction of the race by a flood. Had it not been for the flood, the earth could not have sustained the descendants of Adam. Is not just a demonstration, decisive and final?

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A List of Banned Words

 
Carl Zimmer is teaching a course on science writing. Here's a picture of his classroom.

It's a tough job, but somebody has to do it.

Carl has banned certain words and phrases and he posted the list on his blog: The Index of Banned Words. We can all agree that "breakthrough" and "paradigm shift" must be on the list. What about the others? Share your opinion on The Loom.

I'd like to add "Darwinism," "cancer" (unless the article is actually about cancer), and "revolutionary."

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A Science Literacy Test

 
I missed this Scientific Literacy Quiz that appeared in The Toronto Star last week.

Fortunately Postdiluvian, a med student at the University of Toronto, found it and blogged about it on The Unexamined Life: Science literacy quiz. He didn't say how many he got right. I'm not saying either except to reveal that it was fewer than 26.

Most of the questions are pretty good but one of them is wrong and a couple could have been better worded.

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Tracking a Press Release

 

David Hone recently published a paper on theropod behavior [see: Baby killers: hunting and feeding behaviours of large theropods].

When the paper came out he made up a press release that he distributed to a bunch of people. He tracked the number of articles that picked up on his press release. Initially there was only one report in the media, then five, then twenty [Media tracking].

He was generally satisfied with the articles that appeared but some of his complaints are interesting ...

This leads us onto the next point here. The press release was often regurgitated in very large and near complete chunks. Now that is part of what it is for of course, but equally I would hope that part of their job would be to give it a bit of a literary polish (since they are, you know, writers) and make it a bit more accessible to the public. If not, then the press might as well just publish the press release in full and save themselves a bunch of money on reporters. On the other had, most of them did add in new introductory paragraphs and needless to say this is where the errors mostly came in. So they either copied stuff without writing anything new, or wrote a couple of paragraphs that they got wrong. Really how hard is to check up on a couple of dinosaur facts (one could contact the authors for example) when already 80% of the article is written for you and you don’t have to read the paper itself? Remember that these are supposed to be not just journalists but science reporters and fact checking (especially from a published paper) should be first nature, let alone second nature and is hardly difficult or even especially time consuming, no matter the deadline.

I've never heard of a scientist who makes the effort to personally advertise a paper that's just been published. Usually it's the institution who sends out the press releases and they go directly to the various wire services who specialize in science stories.

I must admit that the concept of publicizing your own work troubles me a bit.

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[Hat Tip: Panda's Thumb]

Advice for Scientists on How to Communicate

 
Carl Zimmer is an excellent science writer. He reviews three books directed at scientists on how they should communicate science to the general public. Two of the books are by science writers and the third is by a former biologist who is now a filmmaker in Hollywood.

Part of Carl's review is on his blog: Book [P]review: For The Scientist.

Three books are coming out this year directed at these scientists. Unscientific America: How Scientific Illiteracy Threatens our Future, by my fellow Discobloggers Sheril Kirshenbaum and Chris Mooney, was the first. I talked to Chris about the book in this Bloggingheads talk. Cornelia Dean of the New York Times is publishing another, called Am I Making Myself Clear?: A Scientist’s Guide to Talking to the Public. It’s a lean, straightforward tour of the media landscape, led by a journalist who has written about science for many years.

The third is by a scientists–but it’s called Don’t Be Such a Scientist: Talking Substance in an Age of Style. The author is Randy Olson, a biologist who headed to Hollywood. Back in 2006, I wrote about his documentary, Flock of Dodos–which was his own response to the events in Kansas. Rather than post a statement on a web site, Olson made a funny movie that not only demonstrated the flim-flammery of creationists, but also showed how dismally evolutionary biologists communicated to those beyond their guild.

All advice is valuable but I'd just like to make sure that everyone keeps things in perspective.

The major goal of science writers is to communicate science to the general public. That's what their profession is all about. If we have not been successful at communicating science properly over the past few decades then isn't it reasonable to put some of the blame on the professionals?

Just out of curiosity, have there been many books written by science writers where they criticize their profession and give advice to fellow science writers on how to improve their science communication skills? Or, have science writers decided that it should be scientists, and not science writers, who need to correct the failures of the past?

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Nobel Laureates: Peter Doherty and Rolf Zinkernagel

 

The Nobel Prize in Physiology or Medicine 1966

"for their discoveries concerning the specificity of the cell mediated immune defence"

Peter C. Doherty (1949 - ) and Rolf M. Zinkernagel (1940 - ) won the Noble Prize in 1996 for their work on the mechanism of cellular immunity (cell-mediated immunity). They were the ones who figured out how T-cells can recognize and kill cells that are infected with a virus.

This is part of the modern era of Nobel Prize awards where the Nobel Foundation is doing a wonderful job of explaining the awards to a scientifically literate general public. Here's the 1996 Press ReleaseTHEME:
Nobel Laureates

Summary

Peter Doherty and Rolf Zinkernagel have been awarded this year's Nobel Prize in Physiology or Medicine for the discovery of how the immune system recognizes virus infected cells. Their discovery has, in its turn, laid a foundation for an understanding of general mechanisms used by the cellular immune system to recognize both foreign microorganisms and self molecules. This discovery is therefore highly relevant to clinical medicine. It relates both to efforts to strengthen the immune response against invading microorganisms and certain forms of cancer, and to efforts to diminish the effects of autoimmune reactions in inflammatory diseases, such as rheumatic conditions, multiple sclerosis and diabetes.

The two Nobel Laureates carried out the research for which they have now been awarded the Prize in 1973-75 at the John Curtin School of Medical Research in Canberra, Australia, where Peter Doherty already held his position and to which Rolf Zinkernagel came from Switzerland as a research fellow. During their studies of the response of mice to viruses, they found that white blood cells (lymphocytes) must recognize both the virus and certain self molecules - the so-called major histocompatibility antigens - in order to kill the virus-infected cells. This principle of simultaneous recognition of both self and foreign molecules has since then constituted a foundation for the further understanding of the specificity of the cellular immune system.

The background to the Laureates' research

The immune system consists of different kinds of white blood cells, including T- and B- lymphocytes whose common function is to protect the individual against infections by means of eliminating invading microorganisms and infected cells. At the same time they must avoid damaging the own organism. What is required is a well developed recognition system that enables lymphocytes to distinguish between on the one hand microorganisms and infected cells, and on the other, the individual´s normal cells. In addition, the recognition system must be able to determine when white blood cells with a capacity to kill should be activated.

In the early 1970s when Peter Doherty and Rolf Zinkernagel had begun their scientific work within immunology, it was possible to distinguish between antibody-mediated and cell- mediated immunity. It was known that antibodies that are produced by B-lymphocytes are able to recognize and eliminate certain microorganisms, particularly bacteria. Far less was known about recognition mechanisms in the cellular immune system, for instance in conjunction with the killing of virus-infected cells by T-lymphocytes. One area where cellular immunity had previously been studied in some detail was, however, transplantation biology. It was known that T-lymphocytes could kill cells from a foreign individual after recognition of certain molecules - the major histocompatibility antigens - in the transplant.

The discovery

Rolf Zinkernagel and Peter Doherty used mice to study how the immune system, and particularly T -lymphocytes, could protect animals against infection from a virus able to cause meningitis. Infected mice developed killer T-lymphocytes, which in a test-tube could kill virus- infected cells. But there was an unexpected discovery: the T-lymphocytes, even though they were reactive against that very virus, were not able to kill virus-infected cells from another strain of mice. What decided whether or not a cell was eliminated by these killer lymphocytes was not only if they were infected with the virus, but also if they carried the "correct" variant of histocompatibility antigens, those of the infected mouse itself. Zinkernagel's and Doherty's findings, which were published in Nature in 1974 (1,2), demonstrated conclusively the requirement for the cellular immune system to recognize simultaneously both 'foreign' molecules (in the present case from a virus) and self molecules (major histocompatibility antigens). What also became obvious was the important function of the major histocompatibility antigens (in man called HLA-antigens) in the individual´s normal immune response and not only in conjunction with transplantation.

The discovery has given an impetus to later research

Zinkernagel's and Doherty´s findings had an immediate impact on immunological research. The wide relevance of their observations concerning the specificity of the T-lymphocytes became apparent in many contexts, both in regard to the ability of the immune system to recognize microorganisms other than viruses, and in regard to the ability of the immune system to react against certain kinds of self tissue. To explain their findings, the two scientists subsequently devised two models; one model was based on a single recognition of 'altered self''(when the histocompatibility antigen has been modified through association with a virus), the other on a 'dual recognition' of both foreign and self. (Fig.) Both the experimental findings and the theoretical models became immensely important in later research. Within a few years, it had been demonstrated that the set of the T- lymphocytes that are allowed to mature and survive in an individual is determined by the ability of the cell to recognize the transplantation antigens of the individual. Therefore, the principle of simultaneous recognition is essential for the ability of the immune system to distinguish between 'self' and 'non-self'.

Further molecular research has both confirmed Zinkernagel's and Doherty's models and clarified the structural basis of their discovery - that a small part (a peptide), for example from a virus, is directly bound to a defined variable part of the body´s own histocompatibility antigens, and that this complex is what is recognized by the specific recognition molecules of T- lymphocytes (T-cell receptors). Taken in all, the clarification of the recognition mechanisms of the T-cells within the cellular immune system has fundamentally changed our understanding of the development and normal function of the immune system and, in addition, has also provided new possibilities for the selective modification of immune reactions both to microorganisms, and to self tissues.

Figure legend: The figure describes how a killer T lymphocyte must recognize both the virus antigen and the self histocompatibility antigen molecule in order to kill a virus-infected target cell. The figure is a modification of the figure published by Zinkernagel and Doherty already 1974 (in Nature 251, p 547).

Relevance for clinical medicine

Many common and severe diseases depend on the function of the cellular immune system and consequently on its mechanisms for specific recognition. Although this naturally applies to infectious diseases, this is also true of a number of chronic inflammatory conditions such as rheumatic diseases, diabetes and multiple sclerosis. Where infectious diseases are concerned, the new knowledge provides a better platform for the construction of new vaccines; one can ascertain exactly what parts of a microorganism are recognized by the cellular immune system, and can specifically focus the production of the vaccine on those parts. Furthermore, regard is paid to the fundamental principles formulated by Doherty and Zinkernagel in trials with vaccination against the emergence of metastases in certain forms of cancer. In many chronic inflammatory diseases, better explanations have been provided for the associations between disease susceptibility and the histocompatibility antigen type carried by an individual. The research that followed from the now awarded discovery has also provided openings for selectively diminishing or altering immune reactions that play a central role in inflammatory diseases.

References

1. Zinkernagel RM, Doherty PC. Restriction of in vitro T cell-mediated cytotoxicity in lymphocytic choriomeningitis within a syngenic and semiallogeneic system. Nature 248, 701- 702, 1974.

2. Zinkernagel RM, Doherty PC. Immunological surveillance against altered self components by sensitised T lymphocytes in lymphocytic choriomeningitis. Nature 251, 547-548, 1974.

3. Doherty PC, Zinkernagel RM. A biological role for the major histocompatibility antigens. Lancet, 1406-1409, 1975.

4. Zinkernagel RM, Doherty PC. MHC restricted cytotoxic T cells: Studies on the biological role of polymorphic major transplantation antigens determining T cell restriction specificity. Advances in Immunology 27, 51-177, 1979.

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Atheist Radio at the University of Toronto

 
The University of Toronto publishes eBulletin once or twice a week to let people know what's going on. This is the official voice of the university. This week's issue features David Leaman (Godless Dave) and his campus radio show Godless: Atheist radio show at UTSC attracts listeners worldwide.

I was interviewed on the show in May and it was lot's of fun [Godless Radio].

Here's what the university's eBulletin has to say about the show.

The atheist and freethinker movements have been picking up steam nationwide and across the world. There is also growing interest at UTSC, with a noteworthy addition to this outspoken community being a radio show titled Godless, which began airing on UTSC’s Fusion Radio in January 2009. It is the only show of its kind at U of T.

The name Godless evokes a reaction from most who hear it, and that's exactly the purpose behind the chosen moniker. The term, brought to light in popular culture by right-winger and controversial figure Ann Coulter through the titling of one of her books, was initially used as a pejorative label. The hosts of the show, however, wear the term as a badge of pride.

"Atheism is a lack of a religious world view. There's no dogma or ritual that surrounds it. In fact, the only thing that atheists by definition will have in common with one another is the mutual lack of belief in a God," says fourth-year mathematics student David Leaman (known as 'Dave' on the air), co-host and founder of the online show. "My own personal brand of atheism is one that embraces evidence-based and logical reasoning along with the scientific method. Using these tools, I've come to the realization that the evidence for the existence of God just doesn't hold up. The idea that applying modern methods of inquiry to the 'big questions' should be a bad thing is actually pretty laughable."

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Monday's Molecule #133: Winner?

 
If you look closely at the two molecules (below) you'll see that the one on that left has an extra bit of polypeptide chain compared to the one on the right. Some part of the protein has been removed to create a smaller version.

This should have reminded you of the kinds of reactions that take place when zymogens are cleaved to produce an active enzyme. This is pepsin, the classic example of such a reaction.

Pepsin is a protease—an enzyme that degrades proteins to small peptides in your stomach during digestion. It is initially synthesized as an inactive precursor called pepsinogen (left). When pepsinogen is secreted into the stomach it is inactive until it is cleaved in an autocatalytic reaction stimulated by HCl secretions. The blue bit sticking out on the right of the figure is chopped off, uncovering the active site in the large cleft in the right center of the molecule. This form of activation makes sense since it's not a good idea to have an active protease in the cytoplasm of your cells.

Pepsin—the protein ferment—has been known since the 1830s. At the end of the nineteenth century Ivan Pavlov carried out a series of experiments in an attempt to understand how digestion in the stomach worked. He learned that the initial secretion containing pepsin was inactive until it was combined with a separate secretion.

Pavlov received the Nobel Prize for his work on digestion.

Only one person guessed the molecule but that person did not figure out that Pavlov was the first one to deduce that digestive enzymes were initially produced in an inactive form. There is no winner this week! Even the "regulars" were stumped this time.

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Here are two different versions of the same enzyme. One of them is the active form and the other is inactive. You should identify the enzyme and briefly explain the difference between the two structures.

This is a famous enzyme whose activity was first detected over one hundred and fifty years ago. The Nobel Laureate associated with the two forms shown above is also very famous. He was the first person to discover that there were active and inactive forms of the enzyme and to provide a reasonable explanation. The Nobel Prize was awarded for many other contributions to the field and not just for this discovery. However, the fact that he is better known for other studies should not detract from his significant contributions to biochemistry.

The first person to identify the molecules and the Nobel Laureate, wins a free lunch. Previous winners are ineligible for six weeks from the time they first won the prize.

There are only six ineligible candidates for this week's reward: Dima Klenchin of the University of Wisconsin at Madison, Dara Gilbert of the University of Waterloo, Anne Johnson of Ryerson University, Cody Cobb, soon to be a graduate student at Rutgers University in New Jersey, Alex Ling of the University of Toronto, and Markus-Frederik Bohn of the Lehrstuhl für Biotechnik in Erlangen, Germany.

I have an extra free lunch for a deserving undergraduate so I'm going to continue to award an additional prize to the first undergraduate student who can accept it. Please indicate in your email message whether you are an undergraduate and whether you can make it for lunch.

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(s) and names the Nobel Laureate(s). Note that I'm not going to repeat Nobel Prizes 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.

Comments will be blocked for 24 hours.

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Monday's Molecule #133

 
Here are two different versions of the same enzyme. One of them is the active form and the other is inactive. You should identify the enzyme and briefly explain the difference between the two structures.

This is a famous enzyme whose activity was first detected over one hundred and fifty years ago. The Nobel Laureate associated with the two forms shown above is also very famous. He was the first person to discover that there were active and inactive forms of the enzyme and to provide a reasonable explanation. The Nobel Prize was awarded for many other contributions to the field and not just for this discovery. However, the fact that he is better known for other studies should not detract from his significant contributions to biochemistry.

The first person to identify the molecules and the Nobel Laureate, wins a free lunch. Previous winners are ineligible for six weeks from the time they first won the prize.

There are only six ineligible candidates for this week's reward: Dima Klenchin of the University of Wisconsin at Madison, Dara Gilbert of the University of Waterloo, Anne Johnson of Ryerson University, Cody Cobb, soon to be a graduate student at Rutgers University in New Jersey, Alex Ling of the University of Toronto, and Markus-Frederik Bohn of the Lehrstuhl für Biotechnik in Erlangen, Germany.

I have an extra free lunch for a deserving undergraduate so I'm going to continue to award an additional prize to the first undergraduate student who can accept it. Please indicate in your email message whether you are an undergraduate and whether you can make it for lunch.

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(s) and names the Nobel Laureate(s). Note that I'm not going to repeat Nobel Prizes 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.

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

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Canadian Gets Booted Out of the Creation Museum

 
Derek Rogers is a computer science student at Dalhousie University in Halifax, Nova Scotia (Canada). I met him in Washington last April. He has been active in the atheist bus campaign and other events promoting a nonreligious point of view.

Derek was at the Secular Student Alliance meeting in Ohio and went along with the group that visited the creation museum. He was asked to leave. Here's the video of him explaining what happened to PZ Myers, Seanna and Steve Watson, and others who had just toured the museum.

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[Hat Tip: Friendly Atheist]

Happy Anniversary!

 
Today is our 41st wedding anniversary.

Here's how Ms. Sandwalk looked back when we first started dating. She looks the same to me today as she did back then.

She has posted an old picture of me on her blog and it's clear that I haven't changed very much either!

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