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Tuesday, February 17, 2009

The Modern Synthesis

 
Most people do not understand current ideas about evolution. The following is a brief summary of the Modern Synthesis of Genetics and Evolution as put forth by evolutionary biologists in the late 1940s.

The idea that life on Earth has evolved was widely discussed in Europe in the late 1700s and the early part of the 1800s. In 1859 Charles Darwin supplied a mechanism—namely natural selection—that could explain how evolution occurred. Darwin's theory of natural selection helped to convince most people that life has evolved and this point has not been seriously challenged in the past one hundred and fifty years.

It is important to note that Darwin's book The Origin of Species by Means of Natural Selection did two things. It summarized all of the evidence in favor of the idea that organisms have descended with modification from a common ancestor. Darwin built a strong case for evolution. In addition, Darwin advocated natural selection as a mechanism of evolution.

Biologists no longer question whether evolution has occurred or is occurring. That part of Darwin's book is now considered to be so overwhelmingly demonstrated that is is often referred to as the FACT of evolution. However, the MECHANISM of evolution is still debated [Evolution Is a Fact and a Theory].

During the first part of this century the incorporation of genetics and population genetics into studies of evolution led to a Neo-Darwinian theory of evolution that recognized the importance of mutation and variation within a population. Natural selection then became a process that altered the frequency of genes in a population and this came to be the minimal definition evolution [What Is Evolution?].

The earliest version of this essay appears on the TalkOrigins Archive.

A later version is at Evolution by Accident.
This point of view held sway for many decades but by the 1940s the classic Neo-Darwinian view was replaced by a new concept that brought together field biology, paleontology, and population genetics. The new version took pains to exclude all mechanisms except natural selection and random genetic drift. This new version was called The Modern Synthesis after the title of a 1942 book by Julian Huxley.

We have learned much since Darwin's time and it is no longer appropriate to claim that natural selection is the only mechanism of evolution. I can understand why this point may not be appreciated by the average non-scientist because natural selection is easy to understand at a superficial level. It has been widely promoted in the popular press and the image of "survival of the fittest" is too powerful and too convenient.

One of the goals of the Modern Synthesis was to reach consensus on the importance of macroevolution. The founders of the Modern Synthesis insisted that macroevolution could be explained by microevolution and no additional mechanisms—such as the bogeyman of saltation—were required.

Ernst Mayr, one of the original founders of the Modern Synthesis, sums it up this way ...
The term "evolutionary synthesis" was introduced by Julian Huxley in Evolution: The Modern Synthesis (1942) to designate the general acceptance of two conclusions: gradual evolution can be explained in terms of small genetic changes ("mutations") and recombination, and the ordering of the genetic variation by natural selection; and the observed evolutionary phenomena, particularly macroevolutonary processes and speciation, can be explained in a manner that is consistent with the known genetic mechanisms.

Ernst Mayr (1980) "Some Thoughts on the History
of the Evolutionary Synthesis" in The Evolutionary Synthesis,
E. Mayr & W.B. Provine eds. Harvard University Press.
The original version of the Modern Synthesis included mechanisms other than natural selection, especially random genetic drift. Later on, there was a hardening of the synthesis so that natural selection became the predominant mechanism and drift was relegated to a bit part (see Mayr quotation, above). The original version is described by Douglas Futuyma as ....
The major tenets of the evolutionary synthesis, then, were that populations contain genetic variation that arises by random (ie. not adaptively directed) mutation and recombination; that populations evolve by changes in gene frequency brought about by random genetic drift, gene flow, and especially natural selection; that most adaptive genetic variants have individually slight phenotypic effects so that phenotypic changes are gradual (although some alleles with discrete effects may be advantageous, as in certain color polymorphisms); that diversification comes about by speciation, which normally entails the gradual evolution of reproductive isolation among populations; and that these processes, continued for sufficiently long, give rise to changes of such great magnitude as to warrant the designation of higher taxonomic levels (genera, families, and so forth).

Futuyma, D.J. in Evolutionary Biology,
Sinauer Associates, 1986; p.12
This description would be incomprehensible to Darwin since he was unaware of genes and genetic drift. The Modern Synthesis differed from Darwinism in four important ways:
  1. It defined evolution as a change in the frequency of alleles in a population; an idea based on population genetics.

  2. In addition to natural selection, it recognized random genetic drift as an important mechanism of evolution.

  3. It recognized that characteristics are inherited as discrete entities called genes. Variation within a population is due to the presence of multiple alleles of a gene. Variation is caused by mutation.

  4. It postulated that speciation is (usually) due to the gradual accumulation of small genetic changes. This is equivalent to saying that macroevolution is simply a lot of microevolution.
The Modern Synthesis was a theory about how evolution worked at the level of genes, phenotypes, and populations whereas Darwinism was concerned mainly with organisms, speciation and individuals. This was a major shift in emphasis and those who fail to appreciate it find themselves out of step with the thinking of evolutionary biologists.

The major controversies among evolutionary biologists today concern the validity of points #2 and #4 (above).

Following the centennial celebrations of the publication of Origin in 1959, there was a gradual hardening of the Modern Synthesis. The 1960s version concentrated almost exclusively on natural selection as a mechanism and random genetic drift was pretty much ignored. Today, there is debate about the relative importance of these two mechanisms and some are calling for an updating of the "hardened" Modern Synthesis.

This update would restore random genetic drift as an important mechanism, recognize neutral theory, and incorporate molecular phylogeny (and the molecular clock).

There are many who believe that the fossil record does not show gradual change but instead long periods of stasis followed by rapid speciation. This model is referred to as Punctuated Equilibrium and it is widely accepted as true, at least in some cases. The debate is over the relative contributions of gradual versus punctuated change, the average size of the punctuations, and the mechanism.

The Modern Synthesis is challenged over the emphasis on gradualism and over the claim that microevolution is sufficient to explain macroevolution. Some evolutionary biologists suggest that evolutionary theory be modified to incorporate mechanisms that occur at levels higher than the population (e.g. species sorting). These scientists advocate an extension called hierarchical theory.

There are other challenges to the Modern Synthesis. Some of them are valid and some of them are silly. But I think it's fair to say that the 50-year old version needs some serious updating to incorporate some of the new concepts.

Some scientists continue to refer to modern evolutionary theory as Neo-Darwinian. In some cases these scientists do not understand that the field has changed but in other cases they are referring to what I have called the Modern Synthesis, only they have retained an old name from the early 1900s.


Monday's Molecule #108: Winner

 
UPDATE: This week's molecule is the genome of ΦX174, a small bacterial virus. It was the first complete genome to be sequenced (Smith et al., 1977, Sanger et al., 1978, Sanger et al., 1978). The sequencing was done in Fred Sanger's lab and Sanger was awarded the Noble Prize a few year later for developing the dideoxy sequencing technology [The Sanger Method of DNA Sequencing].

ΦX174 is interesting because it has overlapping genes—a feature that we now know to be uncommon.

One of the authors on the papers was Michael Smith. He spent a year in Sanger's lab on sabbatical. In 1978 Smith used the ΦX174 sequence in his experiments to develop site-directed mutagenesis (Hutchison et al. 1978). Smith got the Nobel Prize in 1993. He is this week's Nobel Laureate.

This week's winner is James Fraser of the University of California, Berkeley. We will be meeting for lunch in a few months.


Hutchison, C.A. 3rd, Phillips, S., Edgell, M.H., Gillam, S., Jahnke, P., and Smith, M. (1978) Mutagenesis at a specific position in a DNA sequence. J. Biol. Chem. 253:6551-6560.

Sanger, F., Air, G.M., Barrell, B.G., Brown, N.L., Coulson, A.R., Fiddes, C.A., Hutchison, C.A., Slocombe, P.M., and Smith, M. (1977) The nucleotide sequence of bacteriophage phiX174. Nature 265:687-695.

Sanger, F., Coulson, A.R., Friedmann, T., Air, G.M., Barrell, B.G., Brown, N.L., Fiddes, J.C., Hutchison, C.A. 3rd, Slocombe, P.M., and Smith, M. (1978) The nucleotide sequence of bacteriophage phiX174. J. Mol. Biol. 125:225-246.

Smith, M., Brown, N.L., Air, G.M., Barrell, B.G., Coulson, A.R., Hutchison, C.A. 3rd, and Sanger, F. (1977) DNA sequence at the C termini of the overlapping genes A and B in bacteriophage phi X174. Nature 265:702-705.





Today's Monday's Molecule really is a molecule. Your task is to identify the molecule from the cartoon shown here. It won't be sufficient to just find the name of the molecule, you will also have to identify the significance behind determining its chemical structure.

There's one scientist who was involved in that determination who also did some important work based, in part, on knowing the sequence. This scientist was awarded a Nobel Prize for his work but the prize didn't come until 15 years later. Name this Nobel Laureate.

The first person to identify the molecule and the Nobel Laureate wins a free lunch at the Faculty Club. Previous winners are ineligible for one month from the time they first won the prize.

There are eight ineligible candidates for this week's reward: Ramon, address unknown, Jason Oakley of the University of Toronto, John Bothwell from the Marine Biological Association of the UK, in Plymouth (UK), Wesley Butt of the University of Toronto, David Schuller of Cornell University, Nova Syed of the University of Toronto, Dima Klenchin of the University of Wisconsin and undergraduate Alex Ling of the University of Toronto

John, David, and Dima have offered to donate their free lunch to a deserving undergraduate so I'm going to continue to award an additional free lunch to the first undergraduate student who can accept a free lunch. Please indicate in your email message whether you are an undergraduate and whether you came make it for your free lunch (with a friend).

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 reserve the right to select multiple winners if several people get it right.

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


USA Is Ahead of the World in Science Education

 
This falls into the category of, "Wow, I didn't know that!"1. According to a press release from Michigan State University: College Science Requirements Keep US Ahead Of World, Researcher Argues ...
Despite frequent warnings of the inadequacy of education in the United States, citizens here are still among the world's most scientifically literate, a Michigan State University researcher said.

You can thank those general education requirements that force English majors to sit through biology classes and budding engineers to read Hemingway, Jon Miller said.

...

Fifty years after English novelist and physicist C.P. Snow warned of a disturbing lack of scientific literacy among the cultural elite and a parallel literary void among Britain's scientists and technologists, little has changed in most of the world, Miller argued. And that's part of what keeps the U.S. at the forefront of scientific endeavor and technological innovation.

"What makes the American market and society different," he said, "is that we have more science- and technology-receptive citizens and consumers, and as a society we're willing to spend money for basic science and have been doing that for years."

Americans as a group tend to be more open-minded about innovations such as genetically modified food, he said. Scientific reasoning also works its way into such disciplines as law, he noted, where facts are routinely marshaled to support or disprove theories.
Who would 'av thunk it? American are better at critical scientific reasoning because there are more science-receptive citizens. And it even extends to the law.

I guess that's why American courts spend so much time trying to keep superstition out of the science classroom.


1. Personally, I don't think there's all that much difference between science literacy in the USA and other Westeren industrialized nations. However, the idea that the USA is actually superior to other nations does strain belief, somewhat.

Why Are Women Religious?

 
At my talk last Friday I was asked about the field of evolutionary psychology. This seems to be a popular topic among educated non-scientists. I suppose I shouldn't be surprised that most people are only interested in human evolution—that doesn't mean I can't be disappointed.

The person who asked the question wondered why opponents of evolutionary psychology don't get more ink. The implication was clearly that the opponents are in the minority or don't have a very strong case. I should have directed him the the Wikipedia website: Evolutionary psychology controversy. It summarizes the main problems with evolutionary psychology.

Let's look at a recent article by Elisabeth Cornwell, an Assistant Professor of Research at the University of Colorado at Colorado Springs. Her article attempts to explain why women tend to be more religious than men [Why Women Are Bound to Religion: An Evolutionary Perspective]. We may be able to use her article to illustrate some of the problems with explaining human behavior using evolution.
It is because of hormones that male and female brains differ. While there is no evidence for differences in intelligence (as was believed in the nineteenth century and on into the twentieth - women were not even allowed to vote until 1920!), to deny that differences exist is simply wishful thinking. Evolution cares nothing for either misogyny or feminism; it cares not for what is moral or immoral, just or unjust: without caring at all, it builds survival machines to carry genes into the next generation.

But what has this to do with religious beliefs among women? Quite a bit actually. When we look at some of the behavioral and psychological differences between women and men, we can glimpse some of the adaptations necessary for our ancestors' survival.
Emphasizing differences between men and women is a common theme these days. Some of these differences are due to genetic differences between men and women (e.g. hormones) and some are just cultural differences that have no genetic component. The trick is to distinguish between those differences.

When it comes to specific behaviors, such as religious belief, we need to be very careful. Is there a gene for "religious belief" or is this an epiphenomenon, or a cultural thing? If there's no gene controlling "religious belief" then we're not talking about evolution or biological adaptation.
With this in mind, we can begin to understand why it is so essential for women to fit into their social group. Exclusion would have meant extinction since those women who could not live in accord with the other members of their group would have had fewer or no descendants. Thus, the evolutionary pressures that shaped the need to live in harmony with the group pressed more strongly on women than on men. This is not to suggest that there were not strong evolutionary pressure for males, too, to conform, indeed there were. However, males who risked upsetting the status quo and did so successfully would have gained an advantage in their own reproductive success. Females who tried the same would not.
Like most people who advocate the evolution of specific behaviors, Elisabeth Cornwell is not spelling out the details of her proposal. Let's try and fill in the blanks.

The idea that women might feel the need to belong to a group isn't wrong. There may even be some biological differences between men and women (hormones?) that underlie this preference for belonging. But that's not all that Elisabeth Cornwell is proposing.

What she is suggesting is that there may have been a time in the ancient past when women didn't care about fitting into a social group. Then a new mutation arose that changed this behavior so that women with the mutation wanted to be part of a group. The mutation didn't have the same effect in men even though they must have carried it. Because of "evolutionary pressure" this socialization allele increased in the population until almost everyone had it—but it only worked in women.

Alternatively, women may have elected to form strong social groups because it was a smart thing to do. Over time, women risked being ostracized if they didn't conform to the social norm. (That seems to be a common behavior among women, even today. )

So, we have two competing explanations. One is that there's a gene (allele) for socialization that is responsible for this behavior in women, and that this allele arose during the course of human evolution and became fixed because it conferred selective advantage on women who carried it.

The other possible explanation is that women's biology did not change. The evolution of intelligence in primates, millions of years ago, led to formation of social groups in apes because these groups of women made life easier. It was a deliberate decision, made by intelligent apes. This is not biological evolution.
Religion is a human invention, the gods and goddesses that have come and gone during our short history have all displayed the best and (more often) worst human traits. They fell in love, jealousy was common, revenge, anger and trickery prevailed, the struggle for power was universal, and all could be brought to folly and woe due to excessive hubris, greed, and lust. Soap operas pale in comparison! What concerns me, though, is that religion reflected the culture of the times - and, for better or worse, the religions most prominent today are all rather ancient beasts that grew out of a time when women were subservient to men, and often considered as property to be bartered, battered, and controlled.
One of the main criticisms of evolutionary psychology is that its proponents are often guilty of cultural bias. They tend to extrapolate from the culture they know to all of human behavior. This is an important criticism since the stories are not about biological evolution within a small society but about the evolution of human behavior—all humans.

In this case, Elisabeth Cornwell is talking about cultures that date back only 3,000 or 4,000 years. They are the cultures that produced Judaism, Christianity, and Islam. They are not relevant when it comes to discussions about human evolution.

Another criticism of evolutionary psychology is related to the previous one. It's the premise that evolutionary psychologists know enough about pre-historic societies to be able to make reliable statements about evolutionary pressures. As a matter of fact, we simply don't know how our hunter-gatherer ancestors behaved. We don't know if women formed tight-knit social groups that excluded men, or if women living 50,000 years ago tended to be more "religious." Maybe women were smarter than men and they didn't believe the crap that male shamans1 were spouting!
So we are back to our original question: Why do women today continue to fall victim to an archaic system of beliefs that foster misogynistic behavior? Why are women even more likely to be religious than men? The simple answer is that it is safe. Please don't take this as a slight against women -- it isn't. Male/female differences exist, but I'm certainly not suggesting that risk taking is a better option than playing it safe. After all, women are less likely than men to die doing incredibly stupid things (check out the Darwin Awards it is nearly exclusively male 'winners'). But the fact that women are less likely to push the status quo for fear of social exclusion and even retribution makes a lot of evolutionary sense.
Actually it doesn't make a lot of sense from an evolutionary perspective except as an epiphenomon. Female ape brains may be biologically different from male ape brains and those differences may make it easier for females to form groups. The fact that, today, women in Western industrialized nations tend to be more religious than men could be entirely due to culture.

In other cultures, and other times, it might be men who are more devoted to religion. I don't believe that a woman's brain is hard-wired to be more susceptible to superstition than a man's. Nor do I believe that humans evolved a propensity to be superstitious over being rational.


1. shamans is the correct plural of shaman.

[Hat Tip: RichardDawkins.net]

For more, see Pop Evolutionary Psychology, Modern women are excellent gatherers, Changing Your Mind About Evolutionary Psychology, Please Tell Me This Is a Joke, and Changing Your Mind: Are Humans Evolving?.

Junk DNA Is "Dead as a doornail"?

 
I just received an email message from András Pellionisz informing me that in America the concept of junk DNA is "dead as a doornail." He "proves" his case in an article on his website [HoloGenomics].
A Eureka Moment concerning the fractal character of neurons led in turn to a novel picture of genomics where protein structures act back recursively upon their DNA code -- in outright contradiction to prevailing orthodoxy. A household name in neuroscience for his tensor network theory, Dr. András Pellionisz has recently had another far-reaching discovery borne out. This insight has now received striking confirmation in stunning results from the new field of epigenetics -- promising a whole raft of novel medical diagnoses and therapies.

Sunnyvale, Calif. (PRWEB) July 16, 2008 -- A landmark article on "The Principle of Recursive Genome Function" (received December 7, accepted December 18, 2007) by András J. Pellionisz appears online in Springer's e-Journal Cerebellum.

The paper marks the first anniversary of an historic event--the release of pilot results for ENCODE, the Encyclopedia of DNA Elements project. Building on the results of the Human Genome Project, the ENCODE effort revealed a far more complex DNA coding sequence than was ever previously imagined. "There's a lot more going on than we thought," said Collins, who was director of the National Human Genome Research Institute (NHGRI). Dr. Collins issued a mandate a year ago "the scientific community will need to rethink some long-held views".

A happy few did not need to rethink either the "central dogma of molecular biology" (Crick, 1956) or the misnomer of "junk" DNA (Ohno 1972), since they never believed them in the first place. The dictum claiming that a flow of information from proteins back to DNA "never happens" or the idea that 98.7% of the human genome should be disregarded as junk was never very believable.
THEME

Genomes & Junk DNA
There are some interesting scientific debates about the role of noncoding DNA in large genomes. Much of it is junk but there's lot of other functions that we've known about for decades. Many respectable scientists dispute the notion that most of our genome is junk.

Unfortunately, very little of that interesting scientific debate can be seen on András Pellionisz's website. Instead, I direct you to the site in order to see a classic example of a modern kook in action. The site has all of the characteristics of kookdom (see crank) and serves as a self-evident answer to the question Is András Pellionisz a Kook?.


Monday, February 16, 2009

I Wish My Country's Leader Could Say This!

 
I don't think Prime Minister Stephen Harper believes any of the things that Barack Obama says in this video. My country is cutting back on science at the very time when science needs all the support it can get.




[Hat Tip: Pharyngula]

Monday's Molecule #108

 
Today's Monday's Molecule really is a molecule. Your task is to identify the molecule from the cartoon shown here. It won't be sufficient to just find the name of the molecule, you will also have to identify the significance behind determining its chemical structure.

There's one scientist who was involved in that determination who also did some important work based, in part, on knowing the sequence. This scientist was awarded a Nobel Prize for his work but the prize didn't come until 15 years later. Name this Nobel Laureate.

The first person to identify the molecule and the Nobel Laureate wins a free lunch at the Faculty Club. Previous winners are ineligible for one month from the time they first won the prize.

There are eight ineligible candidates for this week's reward: Ramon, address unknown, Jason Oakley of the University of Toronto, John Bothwell from the Marine Biological Association of the UK, in Plymouth (UK), Wesley Butt of the University of Toronto, David Schuller of Cornell University, Nova Syed of the University of Toronto, Dima Klenchin of the University of Wisconsin and undergraduate Alex Ling of the University of Toronto

John, David, and Dima have offered to donate their free lunch to a deserving undergraduate so I'm going to continue to award an additional free lunch to the first undergraduate student who can accept a free lunch. Please indicate in your email message whether you are an undergraduate and whether you came make it for your free lunch (with a friend).

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 reserve the right to select multiple winners if several people get it right.

Comments will be blocked for 24 hours.


IDiots and the Genetic Fallacy.

 
The term Genetic Fallacy is used to describe fallacious arguments that attack an idea based on its origins (genesis) and not its current validity.

The most common (but not the only) examples are attempts to discredit someone's idea by impugning the character of the person who originated the idea. For example, you could try to cast doubt on Thomas Jefferson's views about freedom by attacking his morality. Same with Benjamin Franklin, who, we all know, wasn't a very nice person. That has no bearing on the truth of his ideas or his work on electricity.

In the battle between rationalism and superstition, we can always count on the Intelligent Design Creationists to give us examples of every single logical fallacy. They are very good at irrational thinking.

Here's the latest from Denyse O'Leary: If you accept the argument in Descent of Man, you accept a racist argument. Some of her arguments against science are so classic I wouldn't be surprised if they enter the philosophy textbooks as examples of the important logical fallacies.
Quite honestly, I find current Darwinist efforts to get the old Brit toff off the hook for racism embarrassing. Far from differing from his generation's racist beliefs, Darwin wanted to provide solid scientific support for them. And to the extent that anyone accepts the argument in Descent of Man, they accept a racist argument.

Has anyone noticed how Darwinists carefully protect themselves from having the issue framed bluntly in those terms?


[Image Credit: ThadGuy.com]

Chuck Lorre on How to Become an Atheist

 
Chuck Lorre is a TV producer. One of his shows is Two and a half men, another is The Big Bang Theory. Chuck Lorre has a blog but it's a strange kind of blog—no comments allowed and the titles of each posting are just numbers. Many (all?) of them appear in the credits at the end of his shows.

Here's #240, posted on Feburary 2, 2009.
A wise man once told me that we are all God in drag. I like that. Sometimes when I'm in a public place or sitting at a stop light, I'll watch people walking by and I'll silently say to myself, "He's God. She's God. He's God. She's God." Before long I always find myself feeling a warm sense of affinity for these strangers. The experience is even more powerful when I do this while observing a person who is clearly suffering. On occasion I'll test my little spiritual practice by turning on Fox News. Within minutes I become an atheist.


[Photo Credit: Could Chuck Lorre Be the Smartest Person in Television?]

[Hat Tip: Carmi's Art Life World: Chuck Lorre Makes Me Laugh]

In Praise of Jodrell Bank

 
Jodrell Bank was one of the instruments that excited my imagination back when I was a junior member of the astronomical society. Ms. Sandwalk and I are thinking of visiting the Lake District in England. She would be delighted to take a side trip to see Jodrell Bank.

The photos of the main telescope almost convinced me to be an astronomer—but then I found out that biology was much more challenging!

Mark has posted an article In Praise of Jodrell Bank on Cosmic Variance.




Variation and Natural Selection

 
Here's a photograph of many varieties of hybrid radish. It's from the Botany Photo of the Day posted on Darwin's birthday by Nhu Nguyen to illustrate speciation in action.



Please visit the UBC website to see the entire posting. I'd like to comment on one particular statement. Nhu Nguyen writes,
This is a weedy species that grows in coastal (and some central) areas of California. According to research by Norman Ellstrand's group at UC Riverside, this species is evolving in a quantifiable manner. It is a hybrid between Raphanus sativus, the common radish, and Raphanus raphanistrum.

Curiously, the same hybrid occurs elsewhere in similar climates such as that of South Africa, but something special about ecosytems in California allowed it to proliferate. It is now different enough from either of its parents that Ellstrand's group is considering describing this as a new species. This has occurred within the timespan that the two parents were brought together by humans in California."

There are many color variations of this evolving species. It is exactly through this variation that the process of natural selection works. If allowed to go its own way, some of these color morphs may persist, others may perish, all depending on the selective forces present where they occur. Eventually, each of these via time and selection could become a species of its own. California thus would be the center of diversity for a new group of Raphanus species.
What is the evidence that natural selection is acting one these variants? I doubt that there's any evidence at all.

While it's true that evolution may result in many of these variants becoming separate species, there's no reason to suppose that there are "selective forces" working on different colored flowers. It could just as easily happen that one or more colored variations could become fixed in a new species by random genetic drift.

I'm not sure what the problem is here. Is it just sloppy language on the part of some botanists? Do they use the words "natural selection" as a synonym for "evolution" without thinking about it? Or, are they confirmed adaptationists who actually believe that all visible phenotypes must be subject to selection?

There seem to be a large number of scientists who think that all speciation events are driven by natural selection. This was (mostly) what Darwin thought but I was previously under the impression that this had changed in the 20th century to recognize that random genetic drift plays an important role in speciation.


Does This Look Designed?

 
Check out today's Botany Photo of the Day from the University of British Columbia Botanical Garden and Centre for Plant Research. The species is Euphorbia caput-medusae L. from South Africa.

It's an example of a strange-looking species that most of us are not familiar with. We need to keep in mind that life is complicated and weird.


Sunday, February 15, 2009

Literary Darwinism

 
A reader tells me that Trent University (Peterborough, Ontario, Canada) celebrated Darwin's birthday with a talk by Joseph Carroll on The Historical Position of Literary Darwinism. She asked me what I thought of Literary Darwinism.

I had never heard of it so I asked my good friend "Google" and he (she?) didn't disappoint. There's a Wikipedia entry on Darwinian Literary Studies (aka Literary Darwinism).
As Leda Cosmides and John Tooby indicate in their essay "The Psychological Foundations of Culture," scientific models and theories allow us to sense abstract objects and relationships just as our eyes and ears allow us to sense concrete ones. In Darwinian literary studies, as in evolutionary psychology, "[t]he tools of evolutionary functional analysis function as an organ of perception, bringing the blurry world of human psychological and behavioral phenotypes into sharp focus and allowing one to discern the formerly obscured level of our richly organized species-typical functional architecture."[2] In other words, since the human mind is embodied in evolving organic structures such as the brain, researchers should be able to explain aspects--not only of cognitive systems such as language ability, but of cultural systems such as art and literature--in terms of the environmental factors, or selection pressure, that give rise to them. A chief goal of Darwinian literary studies is to show how the reading and writing of literature contributes to the inclusive fitness of the human organism. In this sense the discipline relates closely to adaptationism, and it shares with the adaptationist social sciences the ultimate goal of understanding human nature.
So it's closely related to adaptationism and evolutionary psychology, eh? I don't think I'm going to like literary Darwinism. Sounds like just another misinterpretation of evolution by a bunch of non-scientists.

Let's look at an example.
A good example of applied Darwinian criticism is Joseph Carroll's reading of Pride and Prejudice, which shows how the fundamental biological problem of mate choice informs the plot of Austen's novel[3]. In this view, the novel narrates a social order in which males compete on the basis of socioeconomic attributes such as money and rank, whereas females compete according to 'personal' attributes such as youth and beauty. The story of Darcy and Elizabeth's courtship establishes a model for partial subversion of this social order, since the couple manage to abide by it even though the proximate causes of their mutual attraction have more to do with the conventionally undervalued attributes of dignity, honesty, kindness, and intelligence. A Darwinian critic might argue that the whole book functions as a tool for humans to perceive, order, and make sense of the conflicting impulses that characterize romantic relationships.
I don't know whether I count as a "Darwinian critic" or not but it seems to me that Austen is pointing out that women can be either smart or stupid when it comes to choosing a mate and so can men. Jane Austin is describing the breakdown of an English social order that existed prior to the nineteenth century. That social order is very different than those in other societies at the same time (e.g. India, China, North American natives), which, in turn, is probably nothing like the society of our ancestors 50,000 years ago. I don't see what this has to do with human evolution—or whatever these English scholars mean by "Darwinism."


Dan Falk Gets It Right!

 
Dan Falk is a Toronto-based science writer and winner of 2002 Canadian Science Writers’ Association Science in Society Journalism Award. He writes for major Canadian newspapers and is a frequent contributer to the CBC television program Quirks and Quarks. He is the author of In Search of Time: Journeys Along a Curious Dimension, which I have not read—an oversight I plan to correct as soon as possible.

I'm critical of many science writers for misrepresenting science in their articles appearing in newspapers or magazines. It's even worse when ordinary journalists attempt to write about science [The Ottawa Citizen Should Be Ashamed of David Warren].

Today I'm deligheted to bring to your attention an excellent article by Dan Falk in today's Toronto Star "[You are here: Your microspot in the universe: What Galileo and Darwin should really be remembered for: making us feel smaller"].

You really should follow the link and read the whole article. Here's the conclusion—I hope it will tempt you.
As physicist Steven Weinberg famously said, "The more the universe seems comprehensible, the more it also seems pointless."

Both Galileo and Darwin showed us that our place in the cosmos is less central – perhaps less special – than we had imagined. For some it has been a bitter pill to swallow. But there is also every reason to rejoice in their discoveries. We are indeed animals, but we are animals that can comprehend the structure of DNA and the unity of life.

And yes, we live in one remote corner of the galaxy, itself one of billions of galaxies, but from this outpost we have probed the fabric of the universe, from the smallest quark to the most distant quasars.

Galileo and Darwin broadened our horizons, perhaps to a greater degree than any other two thinkers in history. As a result of their vision, we live in a larger, richer and more wonderful universe.
Thank-you Dan Falk. It's refreshing to see that kind of writing in a major newspaper. I'm looking forward to the letters to the editor, especially from those who haven't yet swallowed the bitter pill.


[Photo Credit: The photograph of Dan Falk on the University of Toronto campus is from his article, TIME TRAVEL AND THE DOWNING STREET DILEMMA, on the pagebooks.ca website.]

Congratulations Steve Darwin!

 
Steve Darwin is Steve #1000. Find out who he is (no relation to Charles) and why he is #1000 by visiting the website of the National Center for Science Education [Steve Darwin is Steve #1000].


Saturday, February 14, 2009

You Can Lead an Atheist to Evidence, But You Can't Make Him Think

 
Here's a video of Pat Robertson and Ray Comfort—two of the best secret weapons on the atheism side. Just watch this video to see why.




[Hat Tip: Friendly Atheist]

Jerry Coyne Meets Ken Miller

 
Read about it on Coyne's blog [Darwin Day, Philadelphia. 1. I meet Ken Miller].
At any rate, after dinner I met Ken and we chatted about things. The first thing he said to me was that one of his friends advised him to break a beer bottle over my head, which was more than a little intimidating when imparted to me by a guy well over six feet tall looking down on my puny five-foot-eight self! But we discussed our differences, tried to iron out misunderstandings on both of our parts, and amiably shook hands. We will never agree on the science-versus-faith thing, but on most issues we are on the same side, and I admire him in many ways. I was glad that we met.
I'd love to have been there.


Can You Guess Who Wrote This?

 
Yet how the former led to the latter, how it was that complexity emerged and is sustained even in that near-miracle of a chemical factory we call the cell is still largely enigmatic. Self-organisation is certainly involved, but one of the puzzles of evolution is the sheer versatility of many molecules, being employed in a myriad of different capacities. Indeed it is now legitimate to talk of a logic to biology, not a term you will hear on the lips of many neo-Darwinians. Nevertheless, evolution is evidently following more fundamental rules. Scientific certainly, but ones that transcend Darwinism. What! Darwinism not a total explanation? Why should it be? It is after all only a mechanism, but if evolution is predictive, indeed possesses a logic, then evidently it is being governed by deeper principles. Come to think about it so are all sciences; why should Darwinism be any exception?

But there is more. How to explain mind? Darwin fumbled it. Could he trust his thoughts any more than those of a dog? Or worse, perhaps here was one point (along, as it happens, with the origin of life) that his apparently all-embracing theory ran into the buffers? In some ways the former possibility, the woof-woof hypothesis, is the more entertaining. After all, being a product of evolution gives no warrant at all that what we perceive as rationality, and indeed one that science and mathematics employ with almost dizzying success, has as its basis anything more than sheer whimsy. If, however, the universe is actually the product of a rational Mind and evolution is simply the search engine that in leading to sentience and consciousness allows us to discover the fundamental architecture of the universe – a point many mathematicians intuitively sense when they speak of the unreasonable effectiveness of mathematics – then things not only start to make much better sense, but they are also much more interesting. Farewell bleak nihilism; the cold assurances that all is meaningless. Of course, Darwin told us how to get there and by what mechanism, but neither why it is in the first place, nor how on earth we actually understand it.

To reiterate: when physicists speak of not only a strange universe, but one even stranger than we can possibly imagine, they articulate a sense of unfinished business that most neo-Darwinians don't even want to think about. Of course our brains are a product of evolution, but does anybody seriously believe consciousness itself is material? Well, yes, some argue just as much, but their explanations seem to have made no headway. We are indeed dealing with unfinished business. God's funeral? I don't think so. Please join me beside the coffin marked Atheism. I fear, however, there will be very few mourners.
The answer is at ... Darwin was right. Up to a point.


[Hat Tip: RichardDawkins.net]

Friday, February 13, 2009

Moving Darwin

A statue of Charles Darwin was sculpted by Sir Joseph Boehm in 1885. It cost £2200. The money was raised by soliciting individual contributions from individuals around the world and so much money flowed in that there was enough left over to fund research in evolution.

The statue was unveiled on June 9, 1885. Charles Darwin was hugely popular, as you can see by the crowd of people outside the Natural History Museum. The statue was placed in a prominent position at the top of the main staircase in the Central Hall.

In 1927, Darwin wasn't as popular and his statue was moved to make way for an elephant display. The place of honor was soon taken up by a statue of Richard Owen, founder of the museum, and not a huge fan of Darwin [The North Hall Statues].

Darwin, and his friend Huxley, sat in the North Hall, under the main stairs in what became the museum cafeteria. This is not a place of honor and when I saw it there in 2006 I thought it looked very much like the museum was trying to hide Darwin from its visitors.



The Natural History Museum decided that they had better take steps to rehabilitate Darwin in preparation for the 2009 celebrations. So last Spring they moved Darwin back to the original position at the top of the stairs in the Central Hall.

You can watch a video of the statue on the move on the Natural History Museum website [Darwin's statue on the move].

I'm glad they decided to move the statue. While there's a danger of reading too much into the traveling statue, I think it reflects a time in the early 20th century when Darwin's reputation was somewhat eclipsed. At that time, there were many scientists who didn't think that natural selection could explain evolution.



Quotable Quotes

 
From PZ Myers [I get email].
One frequent motif recurs in creationist email: they may believe in god, but they don't believe in paragraphs.


On Re-reading the Origin of Species

 
It's been a great pleasure to read the Origin of Species in preparation for my talk tonight and for our book club meeting last Monday. I had forgotten how clever Darwin was and how he carefully weighs his arguments for evolution.

I had also fallen prey to several myths about the book. For example, I didn't realize that Origin of Species is all about speciation and the difference between species and varieties.

The editors of Current Biology asked several scientists to re-read Origin of Species in honor of Darwin's 200th birthday. The results are published on the journal's website [(Re)Reading The Origin].

I've already mentioned Jerry Coyne's defense of the term "Darwinism" [Jerry Coyne on Darwinism. The contribution from Christiane Nüsslein-Volhard is excellent—she points out one of Dawin's most important arguments and reminds us that it has been largely forgotten because it now seems so obvious.

Many of the scientists comment on the wonderful prose in Origin and on Darwin's delightful style of writing. I agree with them. Mark Ptashne doesn't. He couldn't read the book when he was younger and even today he had to read a condensed version because the original is too difficult! ("Who has the patience to dig through the convoluted sentences, extracting the buried nuggets?")1

At my book club meeting, and in many discussions with non-scientific friends, the dominant impression is that Darwin is a very humble man who almost apologizes for having a good idea. That's not the Darwin I see. Simon Conway Morris isn't fooled either ....

But what suddenly became clear is that this is a book haunted by the ghost of William Paley the grandfather of creationist thinking and exponent of seemingly irrefutable arguments for organic design. The Origin is Darwin's riposte. Its metaphorical power depends on suspense and a scattering of clues, but significantly Paley himself is mentioned only once. And cleverly not in the context of his ideas on organic design but in an oblique dig at the question of natural evil. First and foremost, The Origin is an exorcism of the doctrine of special creation, and conducted by one of the most skilled exorcists science has ever seen. The brief crescendo in the last chapter is preceded by repeated and sudden flashes of disdain, a quick insertion of the knife before the narrative calmly continues in its ostensibly more objective purpose of piling up the evidence. Darwin knew his enemy intimately, but was far too astute to engage in a head-on clash.

Darwin was right, and he knew it. His expressions of doubt are largely rhetorical and how seamless—at least from a distance—is the edifice upon which he constructs his theory. Yet, it is equally intriguing how he conceals his intellect: the carefully marshalled facts are allowed to speak for themselves and the implications introduced with restraint and circumspection—a sotto voce naturalist. Darwin never doubted his abilities.
Why are so many people not able to see this? I think it's because they aren't familiar with the typical English style of understatement and well-disguised sarcasm.

Darwin's contemporaries weren't fooled. You should read Brian Switek's posting on Darwin's Heartache to see how Darwin's friends responded to the book in November 1859. His old Cambridge mentor, Adam Sedgwick, was not happy.

Andrew Berry and Hopi Hoekstra didn't comment on their own reading of Origin of Species; instead they listed the comments of their students in the course evaluations! The good news is that some students actually liked the book.

My favorite review is by Peter Lawrence who, I must confess, is one of my favorite scientists. Peter noticed something that I also noticed; namely, that Darwin's style of argument is very much a lost art. Here's how Peter puts it ...
I had only dipped into this wonderful book in my student days. But what a revelation for a somewhat jaded scientist to read it now! It is not only the brilliance, farsighted and original nature of the ideas, there is the sheer diversity of knowledge, the pervading presence of thought, of simple direct experiments, of debate, of argument, the consideration of other views and the style. In writing and reading scientific articles nowadays, we become imprisoned, constrained in what is considered appropriate and our vocabulary is reduced. Also our sentences are stifled by fashion and by journals that kill invention and independence with their strict word limits and their 'house style.' Just one example: punctuation. Darwin used everything, even the long dash and the exclamation mark. In my scientific writing I have been frequently told that these are not allowed—OK for great literature, but banned from scientific usage. I don't know why, but dulling down our scientific writing is not in our best interest. By contrast, in Darwin's time, Victorian fashion encouraged a flowery style as well as intellectual freedom; he took full advantage of both. He could write explorative and educative prose. He could spend many pages explaining narrow but important distinctions between different viewpoints and, time and again, one can see the outcome of careful reading and deep reflection. Our data-dominated publications, pared down to fit them into limited space, would be much more comprehensible if there were more argument, more explanation and more justification; indeed, if we reflected more, I think we could make big reductions in our published pages by making sure they carry and convey at least one message of note.


1. I suspect he hasn't read The Structure of Evolutionary Theory , either.

Thursday, February 12, 2009

YouTube Birthday Card

 



Happy Birthday Charles Darwin

 
Charles Darwin was born on this day in 1809.

Here are the opening paragraphs of Janet Browne's wonderful biography of Charles Darwin.
He was born into Jane Austen's England. Indeed, the Darwins could have stepped straight out of the pages of Emma, the four girls sharply intelligent about the foibles of others, their father as perceptive as Mr. Knightly. The boys had several equally distinctive qualities. Charles Darwin and his older brother, Erasmus, were obliging and sympathetic young men full of the gentle humour, domestic attachments, and modest traits that made Austin's characters stand out in the drawing rooms of local notables, with a good range of idiosyncratic failings to match. These natural attributes were enhanced by a substantial family fortune. Like sensible Mr Weston with his warm heart and easy financial circumstances, the two were general favourites: "always acceptable," as Emma Woodhouse said of Weston. Behind the scenes presided Mrs. Darwin, a clever, well-educated woman, at one time a friend of the novelist Maria Edgeworth, who now led a retired life, the female counter part to Mr. Woodhouse, "never quite well & never quite ill," according to her sister Kitty.

The Darwins like Austen's fictional families, lived in a sleepy market town in the countryside, in their case in Shrewsbury, the county capital of Shropshire, standing on the River Severn halfway between the manufacturing Midlands and Wales. Further downstream in the Severn Gorge smouldered William Hazledine's ironworks, the driving force of the Industrial Revolution. North-east sat the smoking chimneys of the Potteries. But Shrewsbury itself was untouched by any signs of industrial change.




Dawkins on Chance

 
I know I'm going to be accused of beating a dead horse but as Emile Zucherkandl and Linus Pauling said in 1965 ...
Some beating of dead horses may be ethical, when here and there they display unexpected twitches that look like life.
It is absolutely safe to say that if you meet somebody who claims not to believe in evolution, that person is ignorant, stupid or insane (or wicked, but I’d rather not consider that).

Richard Dawkins
Richard Dawkins has reviewed Jerry Coyne's new book Why Evolution is True in The Times Literary Supplement. The text of the review is posted on RichardDawkins.net [Heat the Hornet].

As you might have guessed, when an adaptationist reviews a book by a fellow adapationist you can expect heaps of praise. Dawkins does not disappoint.

One particular claim caught my eye since Dawkins has made it in the past. I know for a fact that others have pointed out to Dawkins the flaws in this claim. Here's what he says,
Coyne is right to identify the most widespread misunderstanding about Darwinism as the idea that, in evolution, “everything happens by chance”. This common claim is flat wrong – obviously wrong, transparently wrong, even to the meanest intelligence (a phrase that has me actively restraining myself). If evolution worked by chance, it obviously couldn’t work at all.
It's true that to say everything happens by chance is wrong. However, it is not true to say that, "If evolution worked by chance, it obviously couldn’t work at all."

Here's a quotation from the most popular textbook on evolution, Evolution by Douglas J. Futuyma. It's in Chapter 10—a chapter titled Random Genetic Drift: Evolution at Random.

Almost all factors are affected simultaneously by both chance (unpredictable) and nonrandom, or deterministic (predictable), factors.... So it is with evolution. As we will see in the next chapter, natural selection is a deterministic, nonrandom process. But at the same time, there are important random processes in evolution, including mutation and random fluctuations in the frequencies of alleles or haplotypes: the process of random genetic drift.

Genetic drift and natural selection are the two most important causes of allele substitution—that is of evolutionary change—in populations
Futuyma closes the chapter with a summary of the important points. The first two are ...
  1. The frequencies of alleles that differ little or not at all in their effect on organisms' fitness (neutral alleles) fluctuate at random. This process, called random genetic drift, reduces genetic variation and leads eventually to the random fixation of one allele and the loss of the other., unless it is countered by other processes, such as gene flow or mutation.
  2. Different alleles are fixed by chance in different populations.
Thus, according to the textbook, evolution by chance occurs in spite of the fact that Dawkins says, "If evolution worked by chance, it obviously couldn’t work at all."

Now, the only way to reconcile his statement is to assume that either Dawkins doesn't know about random genetic drift, or he uses a non-standard definition of "evolution" (or he is wicked, but I’d rather not consider that ).

I know that Dawkins has written about random genetic drift so I have to assume that he uses a definition of the word "evolution" that excludes it. Since he is using a non-standard definition of evolution, I think it would be wise of him to make this clear in his writing. He should have written something like ...
In my opinion, the only valid mechanism of evolution is evolution by natural selection and that is definitely not a chance process. If natural selection worked by chance it obviously couldn't work at all.


Wednesday, February 11, 2009

Nobel Laureate: Christian de Duve

 

The Nobel Prize in Physiology or Medicine 1974

"for their discoveries concerning the structural and functional organization of the cell"

Christian de Duve (1917 - ) won the Noble Prize in 1974 for discovering lysosomes and peroxisomes. He shared the prize with two other cell biologists; Albert Claude and George Palade.

Here's the Press Release.

THEME:
Nobel Laureates
Whereas Palade is in the first hand the morphologist searching the chemical correlate of the structures he has observed Christian de Duve is the biochemist who through his work can make predictions about new structural entities. Also the work of de Duve was a direct consequence of Claude's contributions in the area of chemical fractionation of cell components. de Duve started his work using differential centrifugation and he looked for the distribution of different enzymes among the four fractions resulting from Claude's procedure. These were nuclei, mitochondria (energy producers of the cell), microsomes (fragmented endoplasmic reticulum) and cell sap. He then found that certain enzymes sedimented such that they could not belong to any of the known morphological components. He discovered that they would sediment with a special class of particles, a fifth fraction. Interestingly all the enzymes were of a kind attacking protoplasmic components and de Duve therefore postulated that they had to be confined to membrane limited particles in order not to damage the cell. In accordance with this he found that agents dissolving membranes liberated the enzymes. It was soon possible for de Duve in collaboration with electron microscopists to make a morphological identification of the isolated components which were named lysosomes.

Lysosomes have now been shown, by de Duve and others, to be engaged in a series of cellular activities during which biological material must be degraded. The lysosomes are used in defense mechanisms, against bacteria, during resorption and secretion. They can also be used for a controlled degradation of the cell in which they are contained, e.g. to remove worn out components. Normally the cell is protected from the aggressive enzymes by protecting membranes but during certain conditions the lysosomal membranes may break down and the lysosomes are then real suicide pills for the cell. In medicine the lysosomes are of interest in many areas. There are a number of hereditary diseases with lysosomal enzyme deficiencies. This leads to accumulation of undigestible material in the lysosomes which swell and engorge the cell so as to prevent its proper functioning.

de Duve has not only a highly dominating role in lysosome research, he is also the discoverer of another cell component, the peroxisome, the function of which is still enigmatic but which may very well offer a story as fascinating as that of the lysosomes in the future.


The images of the Nobel Prize medals are registered trademarks of the Nobel Foundation (© The Nobel Foundation). They are used here, with permission, for educational purposes only.

The Ottawa Citizen Should Be Ashamed of David Warren

 
David Warren writes for the Ottawa Citizen—an otherwise respectable newspaper. Denyse O'Leary is one of Warren's biggest fans. Today's column in the Citizen is about The doctrine of Darwin.

Here are some things that David Warren has to say. Trust me, I'm not making them up; you can check for yourself by following the link to the newspaper.
Darwin's contribution was the mechanism of natural (and later, sexual) selection. This mechanism was simultaneously proposed by Alfred Russel Wallace, a true genius who made many other signal observations and discoveries; but Darwin alone became obsessed with this one, and insisted that it could carry us beyond adaptation within a species, across natural barriers to the creation of entirely new forms, over eons of time. Wallace was not so sure, and to this day, Darwin's notion exists merely as a surmise. It has never been proven.

Which is its great strength. For what cannot be proven can never be disproven, either. The Darwinian account is merely belied by the fossil record, which has provided none of the inter-species "missing links" that Darwin anticipated, and which instead yields only sudden radical changes.
You have to wonder about the intelligence of someone who can write as an authority on Darwin while remaining completely ignorant of the entire field of paleontology. Does Warren go out of his way to avoid reading anything by any science writers, who have been documenting all kinds of transitional fossils, even in the past year?
The man himself was very much a product of his age: a bourgeois Victorian adapted to an intellectual environment in which such fatuities as Utilitarianism and Malthusianism were in the air. In retrospect, he is a redundant character, for Wallace already had the theory, and many others could have drudged out Darwin’s specific points.
You don't have to read a biography of Darwin to recognize the stupidity of this assertion—although reading a book or two is probably a good idea before shooting off your mouth. No, you don't have to read a whole book to learn that Darwin developed the essence of his theory of natural selection more than 15 years before Wallace ever thought of such a thing. Furthermore, Darwin was far, far, ahead of Wallace in his thinking about evolution. Darwin's genius lay in presenting the case for evolution in a way that Wallace—and no one else that we know of—ever could.

All you have to do to find this out is read some rather short articles, or Wikipedia. Is that too much to ask?

As if that's not bad enough, Denyse O'Leary quotes a birthday greeting from David Warren on her blog [Darwinism: Well then, no birthday cake for you, David!].
I oppose Darwinism because it is an intellectual & scientific fraud. I have opposed it all my adult life on that account alone; as I've told you before, I opposed it as crap science when I was an atheist. But I oppose it today with greater & greater passion, because I see that it provides the cosmological groundwork for real evil.
Is that the sort of person who should be writing 200th birthday greetings for the Ottawa Citizen?


Not Saint Darwin

 
John Wilkins has posted a link to his essay in Resonance. Go to his blog (Evolving Thoughts), click on the link, read, and enjoy.

I can't think of an essay/article that better captures the essential reason why Darwin made such an important contribution to science. It takes a philosopher to make the case.1

Here's a teaser ... there's much more were this comes from ....
What we remember Darwin for is a synthesis and the empirical support he brought in its defense. He brought together many ideas that were `in the air', so to speak, reading more widely than almost anyone else as well as doing his experimental and anatomical work, and more importantly, managed to filter out most of the bad ideas.

Darwin's achievement was to identify crucial questions and offer a coherent theoretical account that answered them . For instance, in the first half of the nineteenth century, the reasons for the systematic arrangements of plants and animals, why they were arranged 'group with in group' as he put it, was being explored by idealists like William Swainson [12] and William Macleay [13], who offered Pythagorean accounts based on similarities and magic numbers. Darwin offered a general account—which we call common descent—that explained why this was a fact, but also why it was not regular (for example, extinction is not evenly distributed across all groups).

The broader point I want to make here is about the nature of science. Often as not, it is the synthesizers who reorganize how we view things, and as David Hull [14] and others (e.g., Ellegard [15]) have shown, within ten years of the publication of the Origin, nearly all specialists in the sciences concerned had adopted common descent and transmutation (descent with modification). It was the closest any science has ever come to an actual Kuhnian paradigm shift.


1. Perhaps I should say a "good" philosopher since there are others (Dennett, Ruse) who seem to have missed the point.

Evolution is not "survival of the fittest"

 
By the 6th edition of Origin of Species Darwin had begun to adopt the term "survival of the fittest" and a synonym for "natural selection." His decision was prompted by several colleagues, notably Alfred Russel Wallace. The term "survival of the fittest had recently been coined by Herbert Spencer.

Unfortunately, modern society interprets "survival of the fittest" to mean that only the strong survive. They think of evolution in terms of a winner take all competition between the weak and the strong.

I was reminded of this misconception a few nights ago at our book club meeting. We were discussing Origin of Species and every single member of the group viewed evolution in these terms. Much of the discussion was about the future of human evolution and the book club members were fixated on what kind of mutations would make us stronger and better. What would happen to the poor individuals who couldn't compete?

Michael Shermer has written a nice article in the latest issue of Scientific American: A Skeptic's Take on the Public Misunderstanding of Darwin. His main point deserves to be widely publicized.
Natural selection simply means that those individuals with variations better suited to their environment leave behind more offspring than individuals that are less well adapted. This outcome is known as “differential reproductive success.” It may be, as the second myth holds, that organisms that are bigger, stronger, faster and brutishly competitive will reproduce more successfully, but it is just as likely that organisms that are smaller, weaker, slower and socially cooperative will do so as well.

This second notion in particular makes evolution unpalatable for many people, because it covers the theory with a darkened patina reminiscent of Alfred, Lord Tennyson’s “nature, red in tooth and claw.” Thomas Henry Huxley, Darwin’s “bulldog” defender, promoted this “gladiatorial” view of life in a series of popular essays on nature “whereby the strongest, the swiftest, and the cunningest live to fight another day.” The myth persists. In his recent documentary film Expelled: No Intelligence Allowed, Ben Stein linked Darwinism to Communism, Fascism and the Holocaust.


Jerry Coyne on Darwinism

Jerry Coyne is an adaptationist. Thus, it comes as no great surprise that he is comfortable with equating evolutionary biology and Darwinism. Here's what he writes in defense of Carl Safina's New York Times article [Darwinism must die????].
Well, how much confusion has really been caused by using the term “Darwinism”? How many people have been made to think that we biologists adhere to an ideology rather than a strongly supported theory?
That's a tough question. I'd estimate it at about 3 billion but I could be off by a factor of two.
Would creationism and its country cousin, intelligent design, suddenly vanish if we started using the terms “modern evolutionary theory” (ugh!) or the insidious-sounding “neoDarwinism”? I don’t think so.
Nope. The problem isn't so much how the IDiots interpret the term "Darwinism," it's how the average evolution supporter interprets it. The average person seems to be completely unaware of the fact that natural selection doesn't explain everything about common descent. They are surprised to learn that many modern scientist are not adaptationists or confirmed traditional Darwinists.
“Darwinism” is a compact, four-syllable term for “modern evolutionary theory,” which is ten syllables long.
No it is not. Nobody in their right mind would claim that random genetic drift—the dominant mechanism of evolution—is Darwinian. Nobody in their right mind would suggest that it is just a slight modification of natural selection.

Today we know that new beneficial mutations have only a slight chance of becoming fixed in a population. We know that deleterious mutations can become fixed. And we know that a large percentage of mutations are completely invisible to natural selection but they can, nevertheless, become fixed.

Ryan Gregory made the same point in his posting: Jerry Coyne on Darwinism. So did Eugenie C. Scott and Glenn Branch in Don't Call it "Darwinism".

Jerry Coyne is not stupid. He's well aware of the fact that Darwin didn't know everything. But according to Coyne, the expansion of evolutionary theory hasn't amounted to anything more than simple "refinement" and the term "Darwinism" still encompasses the essence of modern evolutionary theory.

Apparently Coyne has an article about to appear in Current Biology where he says ....
Still, these advances amount to refinements of Darwinism rather than its Kuhnian overthrow. Evolutionary biology hasn’t suffered the equivalent of quantum mechanics. But some biologists, chafing in their Darwinian straitjacket, periodically announce new worldviews that, they claim, will overturn our view of evolution, or at least force its drastic revision. During my career I have heard this said about punctuated equilibrium, molecular drive, the idea of symbiosis as an evolutionary force, evo-devo, and the notion that evolution is driven by the self-organization of molecules. Some of these ideas are worthwhile, others simply silly; but none do more than add a room or two to the Darwinian manse. Often declared dead, Darwinism still refuses to lie down. So by all means let’s retain the term. It is less of a jawbreaker than “modern evolutionary biology,” and has not, as was feared, misled people into thinking that our field has remained static since 1859. What better honorific than “Darwinism” to fête the greatest biologist in history?
This is a remarkable bit of writing. Every modern textbook on evolution has a large section devoted to random genetic drift as a fundamental mechanism of evolution and yet Coyne doesn't even mention it. He also doesn't mention population genetics. Isn't that strange?



Kill all the science writers?

 
Several bloggers are upset enough at Carl Safina that they have posted detailed critiques of his article in the New York Times: Darwinism Must Die So That Evolution May Live.

I not so upset. In fact I mostly agree with the opening paragraphs of Safina's article ...
Equating evolution with Charles Darwin ignores 150 years of discoveries, including most of what scientists understand about evolution. Such as: Gregor Mendel’s patterns of heredity (which gave Darwin’s idea of natural selection a mechanism — genetics — by which it could work); the discovery of DNA (which gave genetics a mechanism and lets us see evolutionary lineages); developmental biology (which gives DNA a mechanism); studies documenting evolution in nature (which converted the hypothetical to observable fact); evolution’s role in medicine and disease (bringing immediate relevance to the topic); and more.

By propounding “Darwinism,” even scientists and science writers perpetuate an impression that evolution is about one man, one book, one “theory.” The ninth-century Buddhist master Lin Chi said, “If you meet the Buddha on the road, kill him.” The point is that making a master teacher into a sacred fetish misses the essence of his teaching. So let us now kill Darwin.
However, it gets worse from then on and this opens the door for serious criticism. Read P.Z. Myers (Darwin is already dead, and we know it) and John Pieret (Charles Darwin Superstar).

I especially like one of the paragraphs from John's posting1 ...
Science writers are a different matter altogether, however. But why should Darwin suffer for their sins? Wouldn't the more efficacious solution be to kill all the science writers? It would at least make a refreshing change from lawyers.


1. John is a lawyer.

Tuesday, February 10, 2009

Fire the Professors!

 
Colleges and universities in Georgia (USA) have faculty members who are experts on human sexual behavior. Horrors!

Here's what one state legislator thinks they should do about it. Wait 'till Ben Stein hears about this!




[Hat Tip: Reed Cartwright on De Rerum Natura]