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Tuesday, May 29, 2012

Monday's Molecule #172

Today's molecule (Tuesday's Molecule) should be quite easy for those of you who have been paying attention to the rules of nomenclature. Be sure to specify the stereochemistry. (The image shows two different views of the same molecule.)

Post your answer as a comment. I'll hold off releasing any comments for 24 hours. The first one with the correct answer wins. I will only post mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch with a very famous person, or me.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your comment.)

Some past winners are from distant lands so their chances of taking up my offer of a free lunch are slim. (That's why I can afford to do this!)

In order to win you must post your correct name. Anonymous and pseudoanonymous commenters can't win the free lunch.

Winners will have to contact me by email to arrange a lunch date.

Comments are invisible for 24 hours. Comments are now open.

UPDATE: The molecule is β-D-glucopyranosyl 1,6-bisphosphate. The winners are Mike Hamilton and Dmitri Tchigvintsev but I'm being a bit generous with Mike because he called it "1,6-diphosphate" and that's not correct.

Winners
Nov. 2009: Jason Oakley, Alex Ling
Oct. 17: Bill Chaney, Roger Fan
Oct. 24: DK
Oct. 31: Joseph C. Somody
Nov. 7: Jason Oakley
Nov. 15: Thomas Ferraro, Vipulan Vigneswaran
Nov. 21: Vipulan Vigneswaran (honorary mention to Raul A. Félix de Sousa)
Nov. 28: Philip Rodger
Dec. 5: 凌嘉誠 (Alex Ling)
Dec. 12: Bill Chaney
Dec. 19: Joseph C. Somody
Jan. 9: Dima Klenchin
Jan. 23: David Schuller
Jan. 30: Peter Monaghan
Feb. 7: Thomas Ferraro, Charles Motraghi
Feb. 13: Joseph C. Somody
March 5: Albi Celaj
March 12: Bill Chaney, Raul A. Félix de Sousa
March 19: no winner
March 26: John Runnels, Raul A. Félix de Sousa
April 2: Sean Ridout
April 9: no winner
April 16: Raul A. Félix de Sousa
April 23: Dima Klenchin, Deena Allan
April 30: Sean Ridout
May 7: Matt McFarlane
May 14: no winner
May 21: no winner
May 29: Mike Hamilton, Dmitri Tchigvintsev


Monday, May 28, 2012

Denyse O'Leary: Catholics & Evolution

As I'm sure you all know, the Intelligent Design Creationists have a small bevy of really, really, smart people who strike fear and dread into the hearts of evolutionary biologists.

Here's Toronto's own Denyse O'Leary giving a lecture at Biola University in October 2010.




The Business of Online Education

John Hawks is interested in putting his lecture on the internet [My foray into online education]. I'll eventually get around to discussing whether this is a good idea or not. Today I want to question his sources.

John Hawks quotes an article by someone named Robert Tracinski as evidence that online education is the wave of the future. Let''s look at that article.

Robert Tracinski writes for The Intellectual Activist, which describes itself like this ...
The Intellectual Activist is especially dedicated to understanding and promoting the revolutionary ideas of the 20th-century novelist and philosopher Ayn Rand — the great champion of the power of reason, the supreme value of the individual, and the unfettered liberty of a capitalist society. TIA serves as a forum for those who are working to gain a deeper understanding of Ayn Rand's fiction and philosophy and applying her ideas to gain new insights in every field of human knowledge.
Rober Tracinski has been called The Intellectual Leader of the Tea Party.

Friday, May 25, 2012

The Importance of the Null Hypothesis

Jonathan Eisen of The Tree of Life is hosting a series of guest postings by the authors of recetnly published papers. The latest is a guest post by Josh Weitz on their paper on BMC Genomics: A neutral theory of genome evolution and the frequency distribution of genes. The paper tries to explain the concept of a pan genome, where closely related species, or strains, each have a subset of the total number of genes in the entire collection of species/strains. Why do some strains and some genes and not others?

Josh Weitz makes a point that bears repeating because most people just don't understand it.
So, let me be clear: I do think that genes matter to the fitness of an organism and that if you delete/replace certain genes you will find this can have mild to severe to lethal costs (and occasional benefits). However, our point in developing this model was to try and create a baseline null model, in the spirit of neutral theories of population genetics, that would be able to reproduce as much of the data with as few parameters as possible. Doing so would then help identify what features of gene compositional variation could be used as a means to identify the signatures of adaptation and selection. Perhaps this point does not even need to be stated, but obviously not everyone sees it the same way. In fact, Eugene Koonin has made a similar argument in his nice paper, Are there laws of adaptive evolution: "the null hypothesis is that any observed pattern is first assumed to be the result of non-selective, stochastic processes, and only once this assumption is falsified, should one start to explore adaptive scenarios''. I really like this quote, even if I don't always follow this rule (perhaps I should). It's just so tempting to explore adaptive scenarios first, but it doesn't make it right.


Squirrels, Dawkins, and Evolution

Richard Dawkins doesn't like the new book by Edward O. Wilson [The Descent of Edward Wilson].

This shouldn't be a surprise to anyone since Wilson has become a supporter of group selection and—even more egregious—a critic of kin selection. Dawkins is a big fan of gene centric adaptation so group selection is heresy. Dawkins thinks that Hamilton's discovery of kin selection ranks right up there with Newton and Darwin, so anyone who casts doubt on kin selection is also a heretic.

I'm not an expert on the details of this debate although my instinct is to think that kin selection is vastly overblown1 and there's nothing obviously wrong with the concepts of group selection or species sorting. However, Dawkins mentions something that raises some important questions about evolution and I wonder what people think.

May 25, 1977

The first Star Wars movie was released on this day in 1977. I was living in Geneva, Switzerland at the time and I didn't get to see the movie until July or August.



Wednesday, May 23, 2012

Better Biochemistry: The Perfect Enzyme

The Biologic Institute is a "research" facility funded by The Discovery Institute of Seattle, WA (USA). From time to time they post articles on their website. A few years ago they posted the following article: Physicists Finding Perfection… in Biology.

I want to address one particular point in that article.
For decades enzymologists have recognized that certain enzymes are catalytically perfect—meaning that they process reactant molecules as rapidly as these molecules can reach them by diffusion. [1] That hinted at a principle of physical perfection in biology, but no one anticipated its breadth until recently.
The point of the article is that some things in biology are "perfect" but this presents a problem for "Darwinism." According to the "scientists" at the Biologic Institute. perfection is beyond the reach of a "Darwinian mechanism." The fact that we observe perfection in biology is evidence for design.

ERV picked up on this theme in a 2009 posting: Having your Ford Pinto and Crashing it Too. That posting seemed to concede the point that enzymes are perfect.

That's the issue I want to discuss.

Flunk the IDiots

Casey Luskin recently offered advice on the The Top Three Flaws in Darwinian Evolution. [see The Top Three Flaws In Evolutionary Theory ] At the end of that post he referred readers to The College Student's Back-to-School Guide to Intelligent Design. This is a remarkable document. It's designed to teach students how to debate their professors and/or disguise their true beliefs in order to pass a class.

Why do the IDiots need such advice? It's because Intelligent Design Creationism is under attack from dogmatic professors who can't think critically and who don't have open minds. The opening section lists examples, such as ...
A professor of biochemistry and leading biochemistry textbook author at the University of Toronto stated that a major public research university “should never have admitted” students who support ID, and should “just flunk the lot of them and make room for smart students.”

Tuesday, May 22, 2012

Free/Cheap Textbooks for Students

Sean Caroll, the physicist, has a blog called Cosmic Variance on the Discover Magazine website.1

Yesterday Sean posted an article by a guest blogger, Marc Sher, a physicist who teaches introductory physics at the College of William and Mary. Marc Sher is promoting something called the nonprofit textbook movement [Guest Post: Marc Sher on the Nonprofit Textbook Movement].

Here's what he says ...
The textbook publishers’ price-gouging monopoly may be ending.

For decades, college students have been exploited by publishers of introductory textbooks. The publishers charge about $200 for a textbook, and then every 3-4 years they make some minor cosmetic changes, reorder some of the problems, add a few new problems, and call it a “new edition”. They then take the previous edition out of print. The purpose, of course, is to destroy the used book market and to continue charging students exorbitant amounts of money.
Now, I usually think of myself as a socialist, so it's a little uncomfortable for me to be defending capitalism, but here goes.

Monday, May 21, 2012

Monday's Molecule #171

Today's molecule is four molecules. You need to correctly identify each one. Then you need to tell me whether each molecule (or a derivative) is found in living cells, and if so, where. That's a total of nine answers.

Post your answers as a comment. I'll hold off releasing any comments for 24 hours. The first one with the correct answers wins. I will only post mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch with a very famous person, or me.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your comment.)

Some past winners are from distant lands so their chances of taking up my offer of a free lunch are slim. (That's why I can afford to do this!)

In order to win you must post your correct name. Anonymous and pseudoanonymous commenters can't win the free lunch.

Winners will have to contact me by email to arrange a lunch date.

Comments are invisible for 24 hours. Comments are now open.

UPDATE:The molecules are: N6-isopentyladenine, hypoxanthine, uridine, and 5-oxyacetic acid uridine. Uridine is found in all RNAs and the other three are found in various tRNA molecules.

There are no winners this week!!!

Winners
Nov. 2009: Jason Oakley, Alex Ling
Oct. 17: Bill Chaney, Roger Fan
Oct. 24: DK
Oct. 31: Joseph C. Somody
Nov. 7: Jason Oakley
Nov. 15: Thomas Ferraro, Vipulan Vigneswaran
Nov. 21: Vipulan Vigneswaran (honorary mention to Raul A. Félix de Sousa)
Nov. 28: Philip Rodger
Dec. 5: 凌嘉誠 (Alex Ling)
Dec. 12: Bill Chaney
Dec. 19: Joseph C. Somody
Jan. 9: Dima Klenchin
Jan. 23: David Schuller
Jan. 30: Peter Monaghan
Feb. 7: Thomas Ferraro, Charles Motraghi
Feb. 13: Joseph C. Somody
March 5: Albi Celaj
March 12: Bill Chaney, Raul A. Félix de Sousa
March 19: no winner
March 26: John Runnels, Raul A. Félix de Sousa
April 2: Sean Ridout
April 9: no winner
April 16: Raul A. Félix de Sousa
April 23: Dima Klenchin, Deena Allan
April 30: Sean Ridout
May 7: Matt McFarlane
May 14: no winner
May 21: no winner



The Top Three Flaws In Evolutionary Theory

Casey Luskin is one of the leading IDiots of the Discovery Institute. He posts frequently on Evolution News & Views. Here's one of his recent posts where he lets us in one the The Top Three Flaws in Evolutionary Theory.

If you've ever wondered why I call them IDiots, this will help you understand.
Unfortunately most public schools do NOT teach about the flaws in evolutionary theory. Instead, they censor this information, hiding from students all of the science that challenges Darwinian evolution. But in a perfect world, if the evidence against Darwinian theory were taught, these would be my top three choices:
  1. Tell students that the fossil record often lacks transitional forms and that there are "explosions" of new life forms, a pattern of radiations that challenges Darwinian evolutionary theory.
  2. Tell students that many scientists have challenged the ability of random mutation and natural selection to produce complex biological features.
  3. Tell students that many lines of evidence for Darwinian evolution and common descent are weak:
    a. Vertebrate embryos start out developing very differently, in contrast with the drawings of embryos often found in textbooks which mostly appear similar.
    b. DNA evidence paints conflicting pictures of the "tree of life". There is no such single "tree."
    c. Evidence of small-scale changes, such as the modest changes in the size of finch-beaks or slight changes in the color frequencies in the wings of "peppered moths", shows microevolution, NOT macroevolution.


Sunday, May 20, 2012

Time to Re-write the Textbooks: RNA has a Fifth Base!!!

From Science Daily via a press release from NewYork-Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College: RNA Modification Influences Thousands of Genes: Revolutionizes Understanding of Gene Expression.
Over the past decade, research in the field of epigenetics has revealed that chemically modified bases are abundant components of the human genome and has forced us to abandon the notion we've had since high school genetics that DNA consists of only four bases.

Now, researchers at Weill Cornell Medical College have made a discovery that once again forces us to rewrite our textbooks. This time, however, the findings pertain to RNA, which like DNA carries information about our genes and how they are expressed. The researchers have identified a novel base modification in RNA which they say will revolutionize our understanding of gene expression.

Their report, published May 17 in the journal Cell, shows that messenger RNA (mRNA), long thought to be a simple blueprint for protein production, is often chemically modified by addition of a methyl group to one of its bases, adenine. Although mRNA was thought to contain only four nucleobases, their discovery shows that a fifth base, N6-methyladenosine (m6A), pervades the transcriptome.
Those who don't know history are destined to repeat it.

Edmund Burke
We've known about modified bases in DNA since the early 1970s so there aren't any modern textbooks that don't mention them. If your high school genetics course didn't mention modified bases it isn't because scientists didn't know of their existence—unless, of course, you graduated from high school more than forty years ago.

We've known about the presence of N6-methyladenosine in mRNA for several decades. Here's the introduction to a 1984 paper by Horowitz et al. (1984).
The most prevalent internal methylated nucleoside in eukaryotic mRNA is N6-methyladenosine (m6A). This modified nucleoside is found in RNAs of higher eukaryotic organisms (1-6), plants (7-9), and viruses (3, 10-12), and occurs at two specific sequences: Gpm6ApC and Apm6ApC (13-17).
Refereences 1-5 are from 1975 meaning that in the published scientific literature the presence of m6A dates back 37 years. That's more than enough time to make it into the textbooks. It's in the textbooks.

Not only that, textbooks also contain references to two other modified bases in mRNA. N7-methylguanylate is common in cap structures and several mRNAs are known to contain inosine (I), a modified form of adenylate.

I blame the science writers at Cornell Medical Center for writing something that is not true and I blame the authors of the paper for hype and exaggeration and for not correcting the press release before it was published. That's not how science is supposed to work.


[Hat Tip: Uncommon Descent: Is there a fifth base in RNA?]

Horowitz, S., Horowitz, A., Nilsen, T.W., Munns, T.W. and Rottman, F.M. (1984) Mapping of N6-methyladenosine residues in bovine prolactin mRNA. PNAS 81:5667-5671. [PDF]


Advice for High School Graduates

The Chicago Tribune has an opinion piece on Open letter to high school grads. You really should read the entire thing but here's part of it ...
If you haven't posted a good academic performance in high school, don't believe a university, its leadership, advertisements or admissions officers who co-sign your promissory note with no responsibility for its payment obligation. They need paying students.

Stoking a deceitful dream on life support — an underappreciated, overfinanced, media-hyped charade — is the real deception, and the weight falls on your back, not theirs.

A shameful, elaborate sham, when one out of two college graduates this year are unemployable in their chosen field.

Look carefully at the costs and benefits of a university education. University officials may not tell you the truth: Enrollments could drop. Bankers will not tell you the truth: Interest income will fall off. Elected officials will not tell you the truth: Elections will be lost. Listen to those really concerned for you carefully.
Who wrote this? It's Walter V. Wendler, who is listed as director of the School of Architecture and former chancellor at Southern Illinois University.

Thursday, May 17, 2012

All IDiots Believe in Evolution!

The title of this post may shock you but bear with me for a minute. I've been trying for years to educate creationists on the meaning of evolution and the strawman term "Darwinism." I've pointed out repeatedly that the the standard minimal definition of evolution ("Evolution is a process that results in heritable changes in a population spread over many generations") should be perfectly acceptable to any IDiot. They don't really reject all of evolution, just the part that causes particular problems for their religion.

Finally, we have an Intelligent Design Creationist who is willing to take the bull by the horns and point out the obvious. Johnnyb explains how his fellow IDiots should think about evolution [How to Talk to Your Professors About Your Darwin Doubts].
So what is one to do? Well, thankfully, our friends the evolutionists have given us a way out. In their zeal to claim consensus on the “fact of evolution,” they have had to steamroll together such a large diversity of opinion into the single term “evolution”, that the word “evolution” no longer has the grand meaning it used to. The only real meaning everyone can agree on is “change in allele frequency over time” – and that is a definition that literally everyone can agree with.

In other words, even if you are a young earth creationist, if your professor asks if you believe in evolution, the legitimate answer is “yes”. Given the common definition of “evolution,” the only thing they are really asking with that question is, “do you believe in genetics?”

Therefore, here is how you can, and, I say, should frame yourself – you believe in evolution. However, there are a few parts of the theory that you disagree with. Don’t be obnoxious, but don’t be overly shy either. Just be frank. Do you believe in evolution? “Yes, but I disagree that common ancestry is universal.” Do you believe in evolution? “Yes, but I don’t think that natural selection alone as a mechanism sufficiently explains life’s diversity.” You don’t even have to put the “yes” and the objection in the same sentence. What do you think about evolution? “The study of evolution is fascinating!” How do you think multicellularity evolved? “I think that multicellularity is a fundamental property of certain organisms, and can’t be evolved piecemeal from the presumed single-celled ancestors.” But you do believe in evolution? “Yes, of course.” Do you think multi-cellular organisms evolved? “Certainly!” From what? “Other multi-cellular organisms.”

If someone challenges you on the definition of evolution, simply challenge them back. What definition of evolution are you using? “I’m using the standard population genetics definition of evolution as the change in gene frequencies over time.” That’s not what evolution is. “What is your definition of evolution?” Evolution means natural selection and common ancestry! “Well, that’s a pretty narrow view of evolution in modern biology. So, while I agree with evolution in general, I don’t agree with your specific view of it.” What’s your specific view? “I’m still learning! But I do find it interesting that….[put your favorite evolutionary or non-evolutionary feature of biology here]”
Let's see how many of his fellow creationists take this advice to heart. Are you listening Denyse?

I'm willing to bet that the vast majority will still never admit that evolution, as defined, is a fact because we can directly observe it happening right before our eyes.