Gerald Fink promotes a new definition of a gene

This is the 2019 Killian lecture at MIT, delivered in April 2019 by Gerald Fink. Fink is an eminent scientist who has done excellent work on the molecular biology of yeast. He was director of the prestigious Whitehead Institute at MIT from 1990-2001. With those credentials you would expect to watch a well-informed presentation of the latest discoveries in molecular genetics. Wouldn't you?

Revisiting the deflated ego problem

Humans are just another animal. All animals share a core set of several thousand genes and all mammals have about the same number of homologous genes (~25,000). The differences between species such as gorillas, bats and whales are due almost exclusively to differences in the timing of expression of these common genes.

This concept is not new. It was the major theme of Stephen Jay Gould's book, Ontogeny and Phylogeny, back in 1977 [Learning About EVO-Devo]. Over the next twenty years or so, the concept was confirmed repeatedly by the work of hundreds of developmental biology labs working mostly with model organisms such as Drosophila (fruit flies). The field is evolutionary developmental biology or "evo-devo" and that work has been nicely summarized in several popular books appearing in the 21st century.

John Mattick's latest attack on junk DNA

John Mattick is the most prominent defender of the idea that the human genome is full of functional sequences. In fact, he is just about the only scientist of any prominence who's on that side of the debate. His main "evidence" is the fact that genomes are pervasively transcribed and that most of the transcripts are functional. Let's look at his latest review paper to see how well this argument stands up to close scrutiny (Mattick, 2018).¹

As you read this post, keep in mind that in 2012 John Mattick was awarded a prize by the Human Genome Organization for proving his hypothesis [John Mattick Wins Chen Award for Distinguished Academic Achievement in Human Genetic and Genomic Research].

The Award Reviewing Committee commented that Professor Mattick’s “work on long non-coding RNA has dramatically changed our concept of 95% of our genome”, and that he has been a “true visionary in his field; he has demonstrated an extraordinary degree of perseverance and ingenuity in gradually proving his hypothesis over the course of 18 years.”

Mattick follows his usual format by giving us his version of history. He has argued for the past 15 years that the scientific community has been reluctant to accept the evidence of massive amounts of regulatory RNA genes because it conflicts with the standard paradigm of the supremacy of proteins. In the past he has claimed that this paradigm is based on the Central Dogma which states, according to him, that the only real function of DNA is to make proteins [How Much Junk in the Human Genome?]. As we shall see, he hasn't abandoned that argument but at least he no longer refers to the Central Dogma for support

Philosophers talking about genes

It's important to define what you mean when you use the word "gene." I use the molecular definition since most of what I write refers to DNA sequences. There's no perfect definition but, for most purposes, a good working definition is: A gene is a DNA sequence that is transcribed to produce a functional product. [What Is a Gene?].

There are two types of genes: protein-coding genes and those that specify a functional noncoding RNA (i.e ribosomal RNA, lincRNA). The gene is the part of the DNA that's transcribed so it includes introns. Transcription is controlled by regulatory sequences such as promoters, operators, and enhancers but these are not part of the gene.

In addition to genes, there are many other functional parts of the genome. In the case of eukaryotic genomes, these include centromeres, telomeres, origins of replication, SARs, and some other bits. None of this is new ... these functions have been known for decades and the working definition I use has been common among knowledgeable experts for half-a-century. Scientists know what they are talking about when they say that the human genome contains about 20,000 protein-coding genes and at least 5,000 genes for non-coding RNAs. They are comfortable with the idea that our genome has lots of other functional regions that lie outside of the genes.

Non-experts may not be familiar with the topic and they may have many misconceptions about genes and DNA sequences but we don't base our science on the views of non-experts.

Because of my interest in this topic, I was intrigued by the title of a new book, The Gene: from Genetics to Postgenomics. I ordered it a soon as I heard about it and I've just finished reading it. The version I read has been translated from German by Adam Bostanci.

Subhash Lakhotia: The concept of 'junk DNA' becomes junk

Continuing my survey of recent papers on junk DNA, I stumbled upon a review by Subash Lakhotia that has recently been accepted in The Proceedings of the Indian National Science Academy (Lakhotia, 2018). It illustrates the extent of the publicity campaign mounted by ENCODE and opponents of junk DNA. In the title of this post, I paraphrased a sentence from the abstract that summarizes the point of the paper; namely, that the 'recent' discovery of noncoding RNAs refutes the concept of junk DNA.

Lakhotia claims to have written a review of the history of junk DNA but, in fact, his review perpetuates a false history. He repeats a version of history made popular by John Mattick. It goes like this. Old-fashioned scientists were seduced by Crick's central dogma into thinking that the only important part of the genome was the part encoding proteins. They ignored genes for noncoding RNAs because they didn't fit into their 'dogma.' They assumed that most of the noncoding part of the genome was junk. However, recent new discoveries of huge numbers of noncoding RNAs reveal that those scientists were very stupid. We now know that the genome is chock full of noncoding RNA genes and the concept of junk DNA has been refuted.

Human genome books

Theme
Genomes
& Junk DNA

I'm trying to read all the recent books on the human genome and anything related. There are a lot of them. Here's a list with some brief comments. You should buy some of these books. There are others you should not buy under any circumstances.

One philosopher's view of random genetic drift

Random genetic drift is the process whereby some allele frequencies change in a population by chance alone. The alleles are not being fixed or eliminated by natural selection. Most of the alleles affected by drift are neutral or nearly neutral with respect to selection. Some are deleterious, in which case they may be accidentally fixed in spite of being selected against. Modern evolutionary theory incorporates random genetic drift as part of population genetics and modern textbooks contain extensive discussions of drift and the influence of population size. The scientific literature has focused recently on the Drift-Barrier Hypothesis, which emphasizes random genetic drift [Learning about modern evolutionary theory: the drift-barrier hypothesis].

Most of the alleles that become fixed in a population are fixed by random genetic drift and not by natural selection. Thus, in a very real sense, drift is the dominant mechanism of evolution. This is especially true in species with large genomes full of junk DNA (like humans) since the majority of alleles occur in junk DNA where they are, by definition, neutral.¹ All of the data documenting drift and confirming its importance was discovered by scientists. All of the hypotheses and theories of modern evolution were, and are, developed by scientists.

Nothing in biology makes sense except in the light of population genetics.

Michael Lynch
You might be wondering why I bother to state the obvious; after all, this is the 21st century and everyone who knows about evolution should know about random genetic drift. Well, as it turns out, there are some people who continue to make silly statements about evolution and I need to set the record straight.

One of those people is Massimo Pigliucci, a former scientist who's currently more interested in the philosophy of science. We've encountered him before on Sandwalk [Massimo Pigliucci tries to defend accommodationism (again): result is predictable] [Does Philosophy Generate Knowledge?] [Proponents of the Extended Evolutionary Synthesis (EES) explain their logic using the Central Dogma as an example]. I looks like Pigliucci doesn't have a firm grip on modern evolutionary theory.

His main beef isn't with evolutionary biology. He's mostly upset about the fact that science as a way of knowing is extraordinarily successful whereas philosophy isn't producing many results. He loves to attack any scientist who points out this obvious fact. He accuses them of "scientism" as though that's all it takes to make up for the lack of success of philosophy. His latest rant appears on the Blog of the American Philosophers Association: The Problem with Scientism.

I'm not going to deal with the main part of his article because it's already been covered many times. However, there was one part that caught my eye. That's the part where he lists questions that science (supposedly) can't answer. The list is interesting. Pigliucci says,

Next to last, comes an attitude that seeks to deploy science to answer questions beyond its scope. It seems to me that it is exceedingly easy to come up with questions that either science is wholly unequipped to answer, or for which it can at best provide a (welcome!) degree of relevant background knowledge. I will leave it to colleagues in other disciplines to arrive at their own list, but as far as philosophy is concerned, the following list is just a start:

• In metaphysics: what is a cause?
• In logic: is modus ponens a type of valid inference?
• In epistemology: is knowledge “justified true belief”?
• In ethics: is abortion permissible once the fetus begins to feel pain?
• In aesthetics: is there a meaningful difference between Mill’s “low” and “high” pleasures?
• In philosophy of science: what role does genetic drift play in the logical structure of evolutionary theory?
• In philosophy of mathematics: what is the ontological status of mathematical objects, such as numbers?

[my emphasis LAM]

Before getting to random genetic drift, I'll just note that my main problem with Pigliucci's argument is that there are other definitions of science that render his discussion meaningless. For example, I prefer the broad definition of science—the one that encompasses several of the Pigliucci's questions [Alan Sokal explains the scientific worldview][Territorial demarcation and the meaning of science]. The second point is that no matter how you define knowledge, philosophers haven't been very successful at adding to our knowledge base. They're good at questions (see above) but not so good at answers. Thus, it's reasonable to claim that science (broad definition) is the only proven method of acquiring knowledge. If that's scientism then I think it's a good working hypothesis.

Now back to random genetic drift. Did you notice that one of the questions that science is "wholly unequiped" to answer is the following: "what role does genetic drift play in the logical structure of evolutionary theory?" Really?

Pigliucci goes on to explain what he means ...

The scientific literature on all the above is basically non-existent, while the philosophical one is huge. None of the above questions admits of answers arising from systematic observations or experiments. While empirical notions may be relevant to some of them (e.g., the one on abortion), it is philosophical arguments that provide the suitable approach.

I hardly know what to say.

How many of you believe that the following statements are true with respect to random genetic drift and evolutionary theory?

1. The scientific literature on all the above is basically non-existent.
2. The philosophical literature is huge.
3. The question does not admit of answers arising from systematic observations or experiments.
4. It is philosophical arguments that provide the suitable approach.

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1. There are some very rare exceptions where a mutation in junk DNA may have detrimental effects.

The Salzburg sixty discuss a new paradigm in genetic variation

Sixty evolutionary biologists are going to meet next July in Salzburg (Austria)to discuss "a new paradigmatic understanding of genetic novelty" [Evolution – Genetic Novelty/Genomic Variations by RNA Networks and Viruses]. You probably didn't know that a new paradigm is necessary. That's because you didn't know that the old paradigm of random mutations can't explain genetic diversity. (Not!) Here's how the symposium organizers explain it on their website ...

What's in Your Genome?: Chapter 4: Pervasive Transcription (revised)

I'm working (slowly) on a book called What's in Your Genome?: 90% of your genome is junk! The first chapter is an introduction to genomes and DNA [What's in Your Genome? Chapter 1: Introducing Genomes ]. Chapter 2 is an overview of the human genome. It's a summary of known functional sequences and known junk DNA [What's in Your Genome? Chapter 2: The Big Picture]. Chapter 3 defines "genes" and describes protein-coding genes and alternative splicing [What's in Your Genome? Chapter 3: What Is a Gene?].

Chapter 4 is all about pervasive transcription and genes for functional noncoding RNAs. I've finally got a respectable draft of this chapter. This is an updated summary—the first version is at: What's in Your Genome? Chapter 4: Pervasive Transcription.

What's in Your Genome? Chapter 4: Pervasive Transcription

I'm working (slowly) on a book called What's in Your Genome?: 90% of your genome is junk! The first chapter is an introduction to genomes and DNA [What's in Your Genome? Chapter 1: Introducing Genomes ]. Chapter 2 is an overview of the human genome. It's a summary of known functional sequences and known junk DNA [What's in Your Genome? Chapter 2: The Big Picture]. Chapter 3 defines "genes" and describes protein-coding genes and alternative splicing [What's in Your Genome? Chapter 3: What Is a Gene?].

Chapter 4 is all about pervasive transcription and genes for functional noncoding RNAs.

Chapter 4: Pervasive Transcription

• How much of the genome is transcribed?
• How do we know about pervasive transcription?
• Different kinds of noncoding RNAs
•         Box 4-1: Long noncoding RNAs (lncRNAs)
• Understanding transcription
•         Box 4-2: Revisiting the Central Dogma
• What the scientific papers don’t tell you
•         Box 4-3: John Mattick proves his hypothesis?
• On the origin of new genes
• The biggest blow to junk?
•         Box 4-4: How do you tell if it’s functional?
• Biochemistry is messy
• Evolution as a tinkerer
•         Box 4-5: Dealing with junk RNA
• Change your worldview

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What's in Your Genome? Chapter 3: What Is a Gene?

I'm working (slowly) on a book called What's in Your Genome?: 90% of your genome is junk! The first chapter is an introduction to genomes and DNA [What's in Your Genome? Chapter 1: Introducing Genomes ]. Chapter 2 is an overview of the human genome. It's a summary of known functional sequences and known junk DNA [What's in Your Genome? Chapter 2: The Big Picture]. Here's the TOC entry for Chapter 3: What Is a Gene?. The goal is to define "gene" and determine how many protein-coding genes are in the human genome. (Noncoding genes are described in the next chapter.)

Chapter 3: What Is a Gene?

• Defining a gene
•         Box 3-1: Philosophers and genes
• Counting Genes
• Misleading statements about the number of genes
• Introns and the evolution of split genes
• Introns are mostly junk
•         Box 3-2: Yeast loses its introns
• Alternative splicing
•         Box 3-2: Competing databases
• Alternative splicing and disease
•         Box 3-3: The false logic of the argument from         complexity
• Gene families
• The birth & death of genes
•         Box 3-4: Real orphans in the human genome
• Different kinds of pseudogenes
•         Box 3-5: Conserved pseudogenes and Ken Miller’s         argument against intelligent design
• Are they really pseudogenes?
• How accurate is the genome sequence?
• The Central Dogma of Molecular Biology
• ENCODE proposes a “new” definition of “gene”
• What is noncoding DNA?
• Dark matter

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Sloppiness in translation initiation

There are two competing worldviews in the fields of biochemistry and molecular biology. The distinction was captured a few years ago by Laurence Hurst commenting on pervasive transcription when he said, "So there are two models; one, the world is messy and we're forever making transcripts we don't want. Or two, the genome is like the most exquisitely designed Swiss watch and we don't understand its working. We don't know the answer—which is what makes genomics so interesting." (Hopkins, 2009).

I refer to these two world views as the Swiss watch analogy and the Rube Goldberg analogy.

The distinction is important because, depending on your worldview, you will interpret things very differently. We see it in the debate over junk DNA where those in the Swiss watch category have trouble accepting that we could have a genome full of junk. Those in the Rube Goldberg category (I am one) tend to dismiss a lot of data as just noise or sloppiness.

The pervasive transcription controversy: 2002

I'm working on a chapter about pervasive transcription and how it relates to the junk DNA debate. I found a short review in Nature from 2002 so I decided to see how much progress we've made in the past 15 years.

Most of our genome is transcribed at some time or another in some tissue. That's a fact we've known about since the late 1960s (King and Jukes, 1969). We didn't know it back then, but it turns out that a lot of that transcription is introns. In fact, the observation of abundant transcription led to the discovery of introns. We have about 20,000 protein-coding genes and the average gene is 37.2 kb in length. Thus, the total amount of the genome devoted to these genes is about 23%. That's the amount that's transcribed to produce primary transcripts and mRNA. There are about 5000 noncoding genes that contribute another 2% so genes occupy about 25% of our genome.

What is a "gene" and how do genes work according to Siddhartha Mukherjee?

It's difficult to explain fundamental concepts of biology to the average person. That's why I'm so interested in Siddhartha Mukherjee's book "The Gene: an intimate history." It's a #1 bestseller so he must be doing something right.

My working definition of a gene is based on a blog post from several years ago [What Is a Gene?].

A gene is a DNA sequence that is transcribed to produce a functional product.

This covers two types of genes: those that eventually produce proteins (polypeptides); and those that produce functional noncoding RNAs. This distinction is important when discussing what's in our genome.

How to read the scientific literature?

Science addressed the problem of How to (seriously) read a scientific paper by asking a group of Ph.D. students, post-docs, and scientists how they read the scientific literature. None of the answers will surprise you. The general theme is that you read the abstract to see if the work is relevant then skim the figures and the conclusions before buckling down to slog through the entire paper.

None of the respondents address the most serious problems such as trying to figure out what the researchers actually did while not having a clue how they did it. Nor do they address the serious issue of misleading conclusions and faulty logic.

I asked on Facebook whether we could teach undergraduates to read the primary scientific literature. I'm skeptical since I believe it takes a great deal of experience to be able to profitably read recent scientific papers and it takes a great deal of knowledge of fundamental concepts and principles. We know from experience that many professional scientists can be taken in by papers that are published in the scientific literature. Arseniclife is one example and the ENCODE papers published in September 2012 are another. If professional scientists can be fooled, how are we going to teach undergraduates to be skeptical?

Proponents of the Extended Evolutionary Synthesis (EES) explain their logic using the Central Dogma as an example

There's a group of biologists who think that the current version of evolutionary theory is insufficient. They want to create an extended evolutionary synthesis that incorporates evo-devo, plasticity, niche construction, evolvability, epigenetics, and other things.

You might be wondering how these things could be incorporated and what that would do to "classic" evolutionary theory. Fortunately, we have a road map provided by Massimo Pigliucci and Gerd Müller in chapter one of Evolution: The Extened Synthesis. They help us out by providing an analogy.

As we will see in the rest of this volume, several of these tenets [of the Modern Synthesis] are being challenged as either inaccurate or incomplete. It is important, however, to understand the kind of challenge being posed here, in order to avoid wasting time on unproductive discussions that missed the point of an extended evolutionary synthesis. Perhaps a parallel with another branch of biology will be helpful. After Watson and Crick discovered the double-helix structure of DNA, and the molecular revolution got started in earnest, one of the first principles to emerge from the new discipline was the unfortunately named "central dogma" of molecular biology. The dogma (a word that arguably should never be used in science) stated that the flow of information in biological systems is always one way, from DNA to RNA to proteins. Later on, however, it was discovered that the DNA > RNA flow can be reversed by the appropriately named process of reverse transcription, which takes place in a variety of organisms, including some viruses and eukaryotes (through retrotransposons). Moreover, we now know that some viruses replicate their RNA directly by means of RNA dependent RNA polymerases, enzymes also found in eukaryotes, where they mediate RNA silencing. Prions have shown us how some proteins can catalyze conformational changes in similar proteins, a phenomenon that is not a case of replication, but certainly qualifies as information transfer. Finally, we also have examples of direct DNA translation to protein in cell-free experimental systems in the presence of ribosomes but not of mRNA. All of these molecular processes clearly demolish the alleged central dogma, and yet do not call for the rejection of any of the empirical discoveries or conceptual advances made in molecular biology since the 1950s. Similarly, we argue, individual tenets of the Modern Synthesis can be modified, or even rejected, without generating a fundamental crisis in the structure of evolutionary theory—just as the Modern Synthesis itself improved upon but did not cause rejection of either Darwinism or neo-Darwinism.

I thank Pigliucci and Müller for giving us a clear idea of the logic behind their attack on the Modern Synthesis.

... I must correct a wrong idea that has been spreading for the past three or four years. It was discovered some years ago that in some cases, the transcription step from DNA to RNA works in the reverse direction. That is nothing surprising. ... it could be predicted that such events could occur. They do occur, indeed, but this must not be taken to mean that information from protein could possibly go back to the genome. ... I am ready to take any bet you like that this is never going to turn out to be the case.

Jacques Monod (1974) p.394The original, and correct, version of the Central Dogma of Molecular Biology was stated clearly by Francis Crick in 1958. Crick restated the Central Dogma of Molecular Biology in a famous paper published in 1970 at a time when the premature slaying of the Central Dogma by reverse transcriptase was being announced (Crick, 1970). According to Crick, the correct, concise version of the Central Dogma is ...

... once (sequential) information has passed into protein it cannot get out again (F.H.C. Crick, 1958)

The central dogma of molecular biology deals with the detailed residue-by-residue transfer of sequential information. It states that such information cannot be transferred from protein to either protein or nucleic acid. (F.H.C. Crick, 1970)

Jim Watson published the well-known, but incorrect, version in his 1960s textbook but anyone who does even a little bit of research will discover that the Crick version is the original [see: The Central Dogma of Molecular Biology].

Here's the summary provided by Francis Crick in his 1970 Nature paper.

Fig. 1. Information flow and the sequence hypothesis. These diagrams of potential information flow were used by Crick (1958) to illustrate all possible transfers of information (left) and those that are permitted (right). The sequence hypothesis refers to the idea that information encoded in the sequence of nucleotides specifies the sequence of amino acids in the protein.

This is important because whenever someone attacks the Central Dogma you can get a good idea of their academic ability by seeing if they understand the concept they attack. In this case, there's a question about proponents of the extended evolutionary synthesis and whether they have a sufficient grasp of evolutionary theory to be challenging it. Pigliucci and Müller have tried to convince us that they know what they are talking about by giving us an analogy; namely, the "demolition" of the Central Dogma of Molecular Biology.

They didn't do their homework. That doesn't inspire confidence in their ability to overthrow modern evolutionary theory.

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Crick, F.H.C. (1958) On protein synthesis. Symp. Soc. Exp. Biol. XII:138-163. [PDF]
Crick, F. (1970) Central Dogma of Molecular Biology. Nature 227, 561-563. [PDF file]
Monod, J. (1974) "On the Molecular Theory of Evolution" reprinted in Mark Ridley (editor) Evolution (1997) p. 389

How do you characterize these scientists?

We've been having a discussion on another thread about ID proponents. Are some of them acting in good faith or are they all lying and deceiving their followers?

I have similar problems about many scientists. I've been reading up on pervasive transcription and the potential number of genes for noncoding, functional, RNAs in the human genome. As far as I can tell, there are only a few hundred examples that have any supporting evidence. There are good scientific reasons to believe that most of the detected transcripts are junk RNA produced as the result of accidental, spurious, transcription.

There are about 20,000 protein-coding genes in the human genome. I think it's unlikely that there are more than a few thousand genes for functional RNAs for a total of less than 25,000 genes.

Here's one of the papers I found.

Guil, S. and Esteller, M. (2015) RNA–RNA interactions in gene regulation: the coding and noncoding players. Trends in Biochemical Sciences 40:248-256. [doi: 10.1016/j.tibs.2015.03.001]

Trends in Biochemical Sciences is a good journal and this is a review of the field by supposed experts. The authors are from the Department of Physiological Sciences II at the University of Barcelona School of Medicine in Barcelona, Catalonia, Spain. The senior author, Manel Esteller, has a Wikipedia entry [Manel Esteller].

Here's the first paragraph of the introduction.

There are more genes encoding regulatory RNAs than encoding proteins. This evidence, obtained in recent years from the sum of numerous post-genomic deep-sequencing studies, give a good clue of the gigantic step we have taken from the years of the central dogma: one gene gives rise to one RNA to produce one protein.

The first sentence is not true by any stretch of the imagination. The best that could be said is that there "may" be more genes for regulatory RNAs (> 20,000) but there's no strong consensus yet. Since the first sentence is an untruth, it follows that it is incorrect to say that the evidence supports such a claim.

It's also untrue to distort the real meaning of the Central Dogma of Molecular Biology, which never said that all genes have to encode proteins. The authors don't understand the history of their field in spite of the fact they are writing a review of that field.

Here's the problem. Are these scientists acting in good faith when they say such nonsense? Does acting in "good faith" require healthy criticism and critical thinking or is "honesty" the only criterion? The authors are clearly deluded about the controversy since they assume that it has been resolved in favor of their personal biases but they aren't lying. Can we distinguish between competent science and bad science based on such statements? Can we say that these scientists are incompetent or is that too harsh?

Furthermore, what ever happened to peer review? Isn't the system supposed to prevent such mistakes?

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Junk DNA doesn't exist according to "Conceptual Revolutions in Science"

The blog "Conceptual Revolutions in Science" only publishes "evidence-based, paradigm-shifting scientific news" according to their home page.

The man behind the website is Adam B. Dorfman (@DorfmanAdam). He has an MBA from my university and he currently works at a software company. Here's how he describes himself on the website.

Methodological naturalism at Dover

I'm one of those scientists who don't think that science as a way of knowing is restricted to investigating natural causes [John Wilkins Revisits Methodological Naturalism ]. I think that science can easily investigate supernatural claims and show that they are wrong. In theory, science might even show that the supernatural exists. Some (most?) philosophers agree. Maarten Boudry is the best known [Is Science Restricted to Methodologial Naturalism?].

This year is the tenth anniversary of Kitzmiller v. Dover Area School District. At that trial, the plaintiffs successfully convinced Judge Jones that intelligent design isn't a science because it invokes supernatural causes. The expert witnesses testified that, by definition, science is limited by methodological naturalism. I disagree with the expert witnesses at the trial and I agree with many leading philosophers that science is not restricted to methodological naturalism [Can Science Test Supernatural Worldviews? ].

Best blog post in the past year

3 Quarks Daily is running their annual contest to pick the best blog posts in the past year. The finalists will be picked by popular vote and the winner will be selected from the finalists by Nick Lane. You can review the rules at: Nick Lane to Judge 6th Annual 3QD Science Prize.

The formal description of the prize is "6th annual prize for the best blog and online-only writing in the category of science." This is important because although the rules refer to "blog posts" and "blog entries" it's clear that most of the nominees are more like online poplar science articles than typical blog posts.

Here's a list of the current nominees ...