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Monday, August 13, 2012

Monday's Molecule #181

Last week's molecule was an intermediate in some amino acid biosynthesis pathways and the enzyme that makes it is the target of Roundup®. Replacing this enzyme with a Roundup® resistant version yields genetically modified food plants [Monday's Molecule #180].

This week's molecule is a lot more complicated. You need to identify the specific type of molecule. Defective metabolism of this molecule is associated with a famous disease. Name the disease.

Post your answers 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.

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. Please try and beat the regular winners. Most of them live far away and I'll never get to take them to lunch. This makes me sad.

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

UPDATE: The molecule is ganglioside GM2. Defects in ganglioside synthesis are responsible for a number of genetic diseases in humans including Tay-Sachs disease. This is the same molecule featured in Monday's Molecule #162 back on March 19, 2012. There was no winner that time.

This week's winner is Matt McFarlane, an undergraduate. He lives in Canada but he's quite far away and probably won't make it for lunch.

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
June 4: Bill Chaney, Matt McFarlane
June 18: Raul A. Félix de Sousa
June 25: Raul A. Félix de Sousa
July 2: Raul A. Félix de Sousa
July 16: Sean Ridout, William Grecia
July 23: Raul A. Félix de Sousa
July 30: Bill Chaney and Raul A. Félix de Sousa
Aug. 7: Raul A. Félix de Sousa
Aug. 13: Matt McFarlane


An Example of "Directed" Mutation and an Idiotic "Gotcha"

There's nothing in modern evolutionary theory that allows for mutations that arise specifically because they will produce a future benefit. That's why we say that mutations are "random" with respect to outcome.

There's nothing in the known history of life that suggests it has a purpose or direction. In particular, there's nothing to suggest that 3.5 billion years of evolution were just advanced preparation for the appearance of Home sapiens. That's why we say that evolution appears unguided and purposeless [Is "Unguided" Part of Modern Evolutionary Theory?]. And that's why anyone who says that life shows evidence of purpose is not being scientific.

Creationists aren't happy about this so they will go to extraordinary lengths to wiggle out of the inescapable conclusion based on solid evidence. The usual excuse is to postulate that god is very sneaky. He/she/it makes a huge effort to hide his/her/its manipulations so that it only appears that evolution is unguided and purposeless. The clever creationists aren't fooled by this sneaky god; they can detect its deception, but scientists can't.

Saturday, August 11, 2012

Humanities Aren't Science? More's the Pity

Science is a way of knowing that is evidence based and requires rational thinking and healthy skepticism. It's the only successful way of knowing that has ever been invented.

Whenever investigators in the humanities discover new knowledge it turns out that they have been using a scientific approach. They've been thinking like a scientist. What else could they be doing?

Maria Konnikova is a graduate student in psychology at Columbia University. She writes in Scientific American that Humanities aren’t a science. Stop treating them like one.

Well, it's certainly true that many disciplines in the humanities are very unscientific—evolutionary psychology comes to mind—but this is one of the first times I've ever heard someone be proud of the fact that they don't think scientifically. Why in the world would she say that?

Turns out she's confused about what science is and what it isn't. She thinks that science requires lots of quantitative data and lots of mathematics and statistics.
Sometimes, there is no easy approach to studying the intricate vagaries that are the human mind and human behavior. Sometimes, we have to be okay with qualitative questions and approaches that, while reliable and valid and experimentally sound, do not lend themselves to an easy linear narrative—or a narrative that has a base in hard science or concrete math and statistics. Psychology is not a natural science. It’s a social science. And it shouldn’t try to be what it’s not.
Hmmmm ... that might explain a lot. I guess if you are seeking knowledge in the social sciences it's okay to use a non-scientific approach to gain knowledge. I wonder what approach they follow? Do they pray for guidance? Use a Ouija board? Or do they just make stuff up?

Maybe Konnikova is just saying that humanities disciplines are not chemistry, physics, biology or geology? Nah, that's too obvious. It doesn't merit an article in "Scientific" American. Maybe we'll find out what she really means when her book comes out in January. It's title is: Mastermind: How to Think Like Sherlock Holmes. Did Sherlock Holmes think like a scientist or did he think like someone in the humanities?


[Hat Tip: Mike the Mad Biologist]

Science and Christianity—Different Ways of Finding Truth?

Chris Mulherin is an Anglican Minister who studies the relationship of science and religion. In this video he claims that science and religion are compatible. Specifically, science and Christianity are compatible.

UPDATE: Eric MacDonald does an excellent job of taking down Chris Mulherin in Science and Religion Again!. MacDonald is a former Anglican priest. (Hat Tip: Jerry Coyne.

He doesn't explain how rising from the dead, miracles, souls, heaven, and a Bible full of lies are compatible with science. Instead, he concentrates on the old saw of different magisteria. Christianity answers different questions than science and discovers different truths.


Id' like to echo the challenge I made some years ago and the one Jerry Coyne issues today [Do both science and faith produce truth?]. Can anyone give us an example of a "truth" discovered by religion—one that we all recognize as genuine knowledge? Name a "why" question that religion answers in a way that we all accept as meaningful and true.1

Those who think that science and religion are compatible like to accuse us of not understanding the serious philosophical issues. I don't think that's correct but, if it is, here's a chance for the serious courtier theologian to set us straight.

Waiting .....


1. It's not good enough to say that if only Christians accept the answer as true, then Christianity has discovered truth. If that were the case then astrology and homeopathy are also valid ways of finding truth even if astologers and homeopaths are the only ones who believe the answers. I'm guessing that no serious philosopher would defend such a ridiculous position.

Is "Unguided" Part of Modern Evolutionary Theory?

Creationists are unhappy with the claim that the evolution of life on Earth appears unguided and purposeless. Casey Luskin would like to think that it's a fundamental part of "the theory of Darwinian evolution" [Unguided or Not? How Do Darwinian Evolutionists Define Their Theory?].
An argument we are increasingly hearing from theistic evolutionists is that the "unguided" or "random" aspects of Darwinian evolution are merely "philosophical gloss" or an "add-on" promoted by new atheists who use bad philosophy. Jay Richards covered this question in his recent dialogue with Alvin Plantinga--see here, here, here, and here for the series. While many new atheists undoubtedly make poor philosophers, the "unguided" nature of Darwinian evolution is not a mere metaphysical "add on." Rather, it's a core part of how the theory of Darwinian evolution has been defined by its leading proponents. Unfortunately, even some eminent theistic and intelligent design-friendly philosophers appear unaware of the history and scientific development of neo-Darwinian theory.
This is wrong in many ways.

Here's the simple explanation ... so simple that even an IDiot should be able to understand it.

Modern evolutionary theory consists of many parts including the mechanisms of evolution. The main mechanisms are natural selection and random genetic drift and those two mechanisms act on populations containing variation. The variation is due to the presence of mutations and mutations arise "randomly" with respect to ultimate purpose or goal.

There are tons of experiments proving that mutations are essentially random. (Let's not get into quibbling about the meaning of "random.")

Now let's look at the history of life on Earth. This is a completely separate subject from evolutionary theory. It's like the difference between the theory of gravity and how and when our particular solar system formed.

Looking all the evidence used to reconstruct the probable history of life we see no evidence whatsoever that it was guided in any particular direction or that there was any underlying purpose. That's why we conclude that the evolution of life on Earth appears unguided. It's a tentative conclusion based on fact and observation and not on "the theory of Darwinian evolution."

While it is true that evolutionary theory doesn't allow for a "guided" mechanism, it isn't true that the history of life has to be devoid of purpose or guidance. There could well be evidence that god intervened or that particular organisms were preferred over others and the history was tilted in one direction. But there's no evidence that this is the case—with the possible exception of beetles.

The history of life looks exactly like it should if it were the result of accident, contingency, and evolution. There's no evidence of god(s). That's what makes the creationists upset, not evolutionary theory.


Friday, August 10, 2012

Only Young Scientists Overthrow Old Concepts?

Max Planck once said ...
A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.
This does not conform to my experience in the biological sciences.

I think that what usually what happens is that a new way of thinking is promoted by well-established investigators. Gradually other scientists are convinced by the evidence to change their minds and the new scientific truth spreads within the community.

When a substantial number of scientists are converted, they start teaching the new concept in graduate and undergraduate courses. This produces a young generation who never heard of the old "truth."

If I'm correct then a new generation of scientists grows up familiar with the new scientific truth but only because the established scientists converted and started training the next generation properly.

When it comes to challenging old established concepts in a discipline I find that initially the younger scientists are often quite conservative unless they just happen to be working on that problem. This shouldn't be a surprise since our young investigators have their hands full just establishing themselves in their field. They don't have time to think about what's going on in the rest of the discipline. In fact, it might be detrimental to their careers to challenge most established concepts.

As I'm writing this I'm having trouble coming up with examples in biology. Most of the conceptual shifts that come to mind are ongoing controversies where it still isn't clear that the new scientific truth will replace the old one. I'm thinking of evo-devo, challenges to evolutionary theory, junk DNA, chemiosmotic theory, metabolism & thermodynamics, the tree of life, photosynthesis, and even new ways of teaching.

Can anyone think of examples were the shift has been completed so we can test the Max Planck hypothesis?

How about the shift from thinking that genes were proteins to genes are DNA?


Thursday, August 09, 2012

Still Digging: Part II

Bet you thought that this horse had been beaten to death when you read Still Digging: Part I.

Ha! You don't know why we call them IDiots!

Here's the latest contribution from lawyer non-scientist David Klinghoffer: Why We Call the Myth of Junk DNA a "Myth"

Still Digging: Part I

Believe it or not, the IDiots are still trying to weasel out of the mistakes they've made in attacking junk DNA.

Here's the problem. Jonathan Wells wrote an entire book on The Myth of Junk DNA. Wells says that back in the early 1970s a substantial number of scientists—he calls them Darwinists—said that all noncoding DNA was junk.

44 Years Ago Today


We got married forty-four years ago today.

Ms. Sandwalk hasn't changed a bit.


"Curiosity" Driven Science

The engineers and technicians have done their job, and what a fantastic job they did! "Curiosity" is now on the surface of Mars and it's time for the science to begin.

Have you been wondering about the scientific mission? The search for life is getting all the publicity but, let's face it, the chances of success are slim.

What about the other missions? Rebecca Ghent of the Dept. of Earth Sciences at the University of Toronto explains why she's interested in the data that "Curiosity" will collect [Curiosity: planetary science and the latest Mars mission].
One of the things I'm interested in is the physical characteristics of planetary regoliths - the surface layer of broken rock, dust, etc., that covers planetary surfaces. It's important to understand how this layer formed and has evolved, because it holds a record of the geological processes that have occurred on each planet. Mars has a very complex surface geological record involving the actions of wind, volcanism, impact cratering, and possibly, water; so this new information about the composition and physical characteristics of the rocks at the Curiosity landing site will provide valuable new insights into the roles of these various processes in forming Mars' surface rocks.
For scientists, the best is yet to come. I hope the science journalists can keep the public focused on the real mission and the importance of the data.


Wednesday, August 08, 2012

Charles Darwin at the London 2012 Olympics

Those Brits know what's important! (They also had a picture of some other scientist, I think his name was Isaac.)



[Hat Tip: Ms. Sandwalk]

TED: Alexander Tsiaras, "It was hard not to attribute divinity to it"

Some of you aren't familiar with TED talks so the recent criticism doesn't make sense (e.g. The Trouble with TED). Here's an example of one of the problems with TED talks. This is a "gosh, gee whiz" kind of talk that's almost completely devoid of information.1

The talk has pretty pictures of the developing human embryo/fetus accompanied by the kind of music that evokes mystery and awe. The author of the video talks of the mystery and why it makes him think of divinity.

The first divinity-inspiring observation concerns collagen. Most collagen molecules form fibers (see Collagen) but those in the eye form sheets in the basal lamina. This is because the eye collagen is a different type of collagen. Here's what Wikipedia says [Collagen IV] ...
Type-IV collagen is a type of collagen found primarily in the basal lamina. The type IV collagen C4 domain at the C-terminus is not removed in post-translational processing, and the fibers link head-to-head, rather than in parallel. Also, type-IV lacks the regular glycine in every third residue necessary for the tight, collagen helix. This makes the overall arrangement more sloppy with kinks. These two features cause the collagen to form in a sheet, the form of the basal lamina.
Does that make you think of god(s)?

Would you pay several thousand dollars to hear this TED talk?



1. Recall that the theme of TED is "Ideas worth spreading." Which ideas in this talk are worth spreading?

Tuesday, August 07, 2012

Changing Ideas About The Origin Of Life

I recommend this article by Enrico Uva: Changing Ideas About The Origin Of Life.

Here are the main points—but you should read the whole thing.

  1. Primordial catalysts were probably not proteins nor RNA
  2. First Energy Source Likely Involved Proton Gradients
  3. Knowledge of New Bacterial Kingdoms Downplays Role of Fermentation In First Cells
You should also read The beginnings of life: Chemistry’s grand question by Ashutosh Jogalekar. Here's an excerpt.
While Miller and his fellow “soupists” blazed the initial paths in origins of life research, a startling new era dawned in the 80s with the discovery of potential life-sustaining factories in the most unlikely environments. The finding that life thrives in deep hydrothermal vents opened a whole new chapter in the field, again avowedly chemical. Black smoker chimneys located miles beneath the ocean have for millions of years been orchestrating a tumultuous union of hot, metal-rich, acidic chemicals arising from volcanic vents with cool alkaline waters. The unholy meeting of these two chemical opposites leads to a violent precipitation of minerals including the silicate mineral olivine, one of the most ubiquitous components of our planet’s rocky landscape. The precipitation of these minerals results in chimney like structures that can be miles high. The convecting thermal currents in these chimneys provide an abundant source of life’s sine qua non – energy. The metals can act as catalysts for simple reactions which involve sulfur, carbon monoxide and water. In recent years, because of the sheer energy hidden inside them, their capacity to catalyze key reactions like the Krebs cycle and concentrate reactants and products in microscopic pores and the uncanny resemblance of some of the iron and sulfur compounds to crucial iron-sulfur cores found in proteins, these mighty smokers have been considered by many scientists to precede or at least accompany the origin of life on the surface. Prominent among the “smokers” are scientists like Nick Lane and the patent attorney Günter Wächterhäuser who moonlights in the field as a “hobby”. These theories provide the “metabolism first” counterpart to the “replication first” camp. Together they may account for both genetic inheritance and chemical metabolism.
It doesn't matter whether you're a soupist or a smoker but you'd better be aware of the controversy. Too many scientists think that the primordial soup is still the best, and only, game in town in spite of its severe problems.


Note to David Klinghoffer, When You find Yourself in a Hole, Stop Digging

Some of you might recall the recent Chromosome 2 kerfuffle. It started when Carl Zimmer asked David Klinghoffer a simple question. Zimmer asked him to describe the evidence to support his claim that the fusion site didn't look like it should if two primitive ape chromosomes had fused to produce human chromosome 2.

Rather than simply answer the question, the IDiots circled the wagons then went into attack mode. Eventually, after a lot of pressure, they got around to answering the question; apparently there is no evidence to support their claim [And Finally the Hounding Duck Can Rest].

Of course by then they were so deep in their hole that the sun don't shine.

Monday's Molecule #180

It's Tuesday, so it must be time for Monday's Molecule.... Oops.1

Last week we looked at an important intermediate in the Calvin cycle—the main pathway for fixing carbon dioxide in many species [Monday's Molecule #179]. Today we're going to look at the intermediate in another pathway. Name the molecule, the common name will do.

Discovery of this molecule, and the pathway it's involved in, was an important contribution to understanding basic metabolism in most cells. The enzyme that makes it has been characterized. It's now one of the most widely studied enzymes in biochemistry. The pathway is essential for all species, with a few minor exceptions.

This knowledge has been exploited by technology to an extent never imagined only 50 years ago. Name the technology and how it makes use of what we know about the enzyme and the pathway. For extra bonus points, explain how the molecule got it's root Japanese name.

Post your answers 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. Please try and beat the regular winners. Most of them live far away and I'll never get to take them to lunch. This makes me sad.

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

UPDATE:The molecule is 5-enolpyruvylshikimate 3-phosphate an intermediate in the chorismate pathway and the synthesis of tryptophan, phenylalanine, and tyrosine. The enzyme that produces this product is EPSP synthase and some bacterial versionsof this enzyme are resistant to glyphosate, the active ingredient in the herbicide Roundup®.

The gene for the resistant enzyme can be inserted into crop plants making them resistant to Roundup®.

The winner would have been Ben but I can't identify that person. The winner is Raul A. Félix de Sousa.

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
June 4: Bill Chaney, Matt McFarlane
June 18: Raul A. Félix de Sousa
June 25: Raul A. Félix de Sousa
July 2: Raul A. Félix de Sousa
July 16: Sean Ridout, William Grecia
July 23: Raul A. Félix de Sousa
July 30: Bill Chaney and Raul A. Félix de Sousa
Aug. 7: Raul A. Félix de Sousa


1. I got confused because yesterday was Simcoe Day.