Last week's molecule was malonate (propanedioic acid). A derivative of malonate called malonyl-CoA is a key intermediate in fatty acid synthesis. Bill Chaney was the first person to identify the molecule and describe its function [Monday's Molecule #214].
Recently I've been having a discussion with the Chair of my department about whether undergraduates in introductory biochemistry courses should memorize structures. He thinks they should. I wondered whether all the professors in my department could draw the structures of some important molecules. Here are a couple of molecules that you might be able to recognize. How many of you can identify them without checking a textbook?
How many of you can identify them even with a textbook? I'll need a fairly exact identification. Be sure to specify "top" and "bottom" molecules.
Email your answers to me at: Monday's Molecule #215. I'll hold off posting your answers for 24 hours. The first one with the correct answer wins. I will only post the names of people with 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 email message.)
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Monday, September 16, 2013
Move This Book?
I noticed a couple of books in the Science section of my local bookstore. One was by a guy named Meyer (Stephan C. Meyer) and the other was by someone named Myers (PZ Myers). I bought the one by Myers because I already had the other one.
There are some people who get upset by seeing these books in the Science section. Some of these people even like to move them to other sections, such as religion and/or philosophy. I even did it myself on one or two occasions in the past. Lately, however, I've become somewhat less dogmatic about the creationist books. They are, after all, books about science even though they may try to bring religion into science. That does not mean their view are non-scientific. Many of those books are no worse than some of the other "science" books on the shelf that have nothing to do with religion.
What would you do? Here are the choices ...
Amazon puts The Happy Atheist in the "Religion and Spirituality" category. Does it belong in the Science section of local bookstores?
There are some people who get upset by seeing these books in the Science section. Some of these people even like to move them to other sections, such as religion and/or philosophy. I even did it myself on one or two occasions in the past. Lately, however, I've become somewhat less dogmatic about the creationist books. They are, after all, books about science even though they may try to bring religion into science. That does not mean their view are non-scientific. Many of those books are no worse than some of the other "science" books on the shelf that have nothing to do with religion.
What would you do? Here are the choices ...
- Move the Meyer books to another section.
- Move the Myers books to another section.
- Move both books to other sections.
- Leave both books in the Science section.
Amazon puts The Happy Atheist in the "Religion and Spirituality" category. Does it belong in the Science section of local bookstores?
Friday, September 13, 2013
Creationist Quotes
"Quote mining" can be fun. Here are some actual quotes taken from online forums. They are spoken by atheist actors.
Someone recently asked me why I mock creationists when I should be giving them more respect.
Someone recently asked me why I mock creationists when I should be giving them more respect.
Sean Carroll: "What Is Science?"
I've been meaning to comment on Sean Carroll's post from last July (July 3, 2013) but there always seems to be something else that commands my attention. The issue is important, in fact I've just finished an entire book on the question (Philosophy of Pseudoscience: Reconsidering the Demarcation Problem edited by M. Pigliucci and M. Boudry).
Sean Carroll (the physicist)1 has a view that's quite similar to my own. Read his post at: What Is Science?. Here are some key points.
Sean Carroll (the physicist)1 has a view that's quite similar to my own. Read his post at: What Is Science?. Here are some key points.
Better Biochemistry: Teaching ATP Hydrolysis for the MCAT
I'm digesting the idea that many American biochemistry courses teach to the MCAT exam [see Better Biochemistry: Teaching to the MCAT?]. What this means is that the scientists who teach biochemistry are willing to let the curriculum be established by a group of American medical schools (AAMC). That organization has put up a website to guide faculty members and students in preparation for the 2015 MCAT exam [MCAT2015: Biological and Biochemical Foundations of Living Systems].
One of the links takes you to a chemwiki at the University of California, Davis: Biological Chemistry. From there you can click on several topics. I picked ATP/ADP to see what kind of information the MCAT thinks is appropriate. The information on the ATP website is provided by Tiffany Lui of the University of California, Davis so it's not something that AAMC created. Nevertheless, it is presumably indicative of the sort of thing that might appear on the MCAT exam.
One of the links takes you to a chemwiki at the University of California, Davis: Biological Chemistry. From there you can click on several topics. I picked ATP/ADP to see what kind of information the MCAT thinks is appropriate. The information on the ATP website is provided by Tiffany Lui of the University of California, Davis so it's not something that AAMC created. Nevertheless, it is presumably indicative of the sort of thing that might appear on the MCAT exam.
Thursday, September 12, 2013
Humans Are Still Evolving
Sir David Attenborough said something stupid the other day [Sir David Attenborough: Humans have stopped evolving]. (Not for the first time.) He said ...
But what about his specific claim that natural selection doesn't work on humans any more? I covered that in earlier posts but John Hawks has corrected him today [Humans are still evolving, and soon we'll know a lot more about it]. I love it when I agree with John Hawks! (That's me, visiting him in his lab in Madison, Wisconsin.)
Because if natural selection, as proposed by Darwin, is the main mechanism of evolution – there may be other things, but it does look as though that’s the case – then we’ve stopped natural selection.The headline says that humans have stopped evolving. If that's what he really said then it's easy to prove him wrong by showing that there's a lot more to evolution than natural selection [Have Humans Stopped Evolving?].
We stopped natural selection as soon as we started being able to rear 95–99 per cent of our babies that are born.
We are the only species to have put a halt to natural selection, of its own free will, as it were.
But what about his specific claim that natural selection doesn't work on humans any more? I covered that in earlier posts but John Hawks has corrected him today [Humans are still evolving, and soon we'll know a lot more about it]. I love it when I agree with John Hawks! (That's me, visiting him in his lab in Madison, Wisconsin.)
Better Biochemistry: Teaching to the MCAT?
Theme
Better BiochemistryI view science education as a way of teaching students how to think critically. In that sense, it's not any different than education in the arts and humanities. In my opinion, biochemistry should be taught as a bunch of fundamental concepts and principles that will help students understand the basics of life at the molecular level. The course will demonstrate how to think critically and how we come to know what we know—if we teach it correctly. I believe that biochemistry should be taught from an evolutionary perspective since that's the best way to achieve fundamental understanding.
The last thing we should be doing in an undergraduate biochemistry course is to ask students to memorize enzymes, structures, and pathways and regurgitate them on an exam. We should not just be teaching the biochemistry of humans since that does not provide students with a broad view of life and where humans came from. Such an approach also makes biochemistry seem like it's only important because it can contribute to health. We have plenty of evidence that this is the wrong way to teach.
Better BiochemistryI view science education as a way of teaching students how to think critically. In that sense, it's not any different than education in the arts and humanities. In my opinion, biochemistry should be taught as a bunch of fundamental concepts and principles that will help students understand the basics of life at the molecular level. The course will demonstrate how to think critically and how we come to know what we know—if we teach it correctly. I believe that biochemistry should be taught from an evolutionary perspective since that's the best way to achieve fundamental understanding.
The last thing we should be doing in an undergraduate biochemistry course is to ask students to memorize enzymes, structures, and pathways and regurgitate them on an exam. We should not just be teaching the biochemistry of humans since that does not provide students with a broad view of life and where humans came from. Such an approach also makes biochemistry seem like it's only important because it can contribute to health. We have plenty of evidence that this is the wrong way to teach.
Wednesday, September 11, 2013
The Happiest Countries
Why do the people of these countries think they are happy? Why isn't the USA in the top ten? [World’s Happiest Countries In 2013, According To The UN]
I recently visited #1, #2, #5, #7 and #9 and I can confirm that the citizens of those countries do, indeed, think they are happy. I also visited #17 a few months ago and the citizens of that country do not seem happy. It's probably worse today than it was a few months ago.
I recently visited #1, #2, #5, #7 and #9 and I can confirm that the citizens of those countries do, indeed, think they are happy. I also visited #17 a few months ago and the citizens of that country do not seem happy. It's probably worse today than it was a few months ago.
Science and Mystery
One of the criticisms of science (narrow definition) is that its reductionist approach is simplistic and materialistic. Here's how Jesus and Mo dealt with that issue last month.
Monday, September 09, 2013
What Is "Science" According to George Orwell?
I'm about to start teaching my course on "Scientific Misconceptions" and one of the most important issues is defining science and dealing with the demarcation problem. Vincent Joseph Torley is also interested in this question—for a different reason—and he discovered an 1945 essay by George Orwell (Eric Arthur Blair (1903-1950)).
It's worth quoting the relevant passages.
Doublethink means the power of holding two contradictory beliefs in one's mind simultaneously and accepting both of them.
George Orwell
George OrwellI agree with Orwell when he prefers the broad definition of science. I see it as a way of knowing that can be applied to any discipline. I think that everyone should become more scientifically literate but by that I don't mean they should lean more about metabolic pathways or quantum chromodynamics. I mean that they should become more familiar with the scientific approach to acquiring knowledge. That's the fundamental skill that we need to learn.
It's worth quoting the relevant passages.
Doublethink means the power of holding two contradictory beliefs in one's mind simultaneously and accepting both of them.
George Orwell
In last week’s Tribune, there was an interesting letter from Mr. J. Stewart Cook, in which he suggested that the best way of avoiding the danger of a “scientific hierarchy” would be to see to it that every member of the general public was, as far as possible, scientifically educated. At the same time, scientists should be brought out of their isolation and encouraged to take a greater part in politics and administration.Every war when it comes, or before it comes, is represented not as a war but as an act of self-defense against a homicidal maniac.
As a general statement, I think most of us would agree with this, but I notice that, as usual, Mr. Cook does not define Science, and merely implies in passing that it means certain exact sciences whose experiments can be made under laboratory conditions. Thus, adult education tends “to neglect scientific studies in favour of literary, economic and social subjects”, economics and sociology not being regarded as branches of Science, apparently. This point is of great importance. For the word Science is at present used in at least two meanings, and the whole question of scientific education is obscured by the current tendency to dodge from one meaning to the other.
Science is generally taken as meaning either (a) the exact sciences, such as chemistry, physics, etc., or (b) a method of thought which obtains verifiable results by reasoning logically from observed fact.
If you ask any scientist, or indeed almost any educated person, “What is Science?” you are likely to get an answer approximating to (b). In everyday life, however, both in speaking and in writing, when people say “Science” they mean (a). Science means something that happens in a laboratory: the very word calls up a picture of graphs, test-tubes, balances, Bunsen burners, microscopes. A biologist, and astronomer, perhaps a psychologist or a mathematician is described as a “man of Science”: no one would think of applying this term to a statesman, a poet, a journalist or even a philosopher. And those who tell us that the young must be scientifically educated mean, almost invariably, that they should be taught more about radioactivity, or the stars, or the physiology or their own bodies, rather than that they should be taught to think more exactly.
George OrwellI agree with Orwell when he prefers the broad definition of science. I see it as a way of knowing that can be applied to any discipline. I think that everyone should become more scientifically literate but by that I don't mean they should lean more about metabolic pathways or quantum chromodynamics. I mean that they should become more familiar with the scientific approach to acquiring knowledge. That's the fundamental skill that we need to learn.
Clearly, scientific education ought to mean the implanting of a rational, sceptical, experimental habit of mind. It ought to mean acquiring a method – a method that can be used on any problem that one meets – and not simply piling up a lot of facts. Put it in those words, and the apologist of scientific education will usually agree. Press him further, ask him to particularise, and somehow it always turns out that scientific education means more attention to the sciences, in other words – more facts. The idea that Science means a way of looking at the world, and not simply a body of knowledge, is in practice strongly resisted. I think sheer professional jealousy is part of the reason for this. For if Science is simply a method or an attitude, so that anyone whose thought-processes are sufficiently rational can in some sense be described as a scientist – what then becomes of the enormous prestige now enjoyed by the chemist, the physicist, etc. and his claim to be somehow wiser than the rest of us?Where did the George Orwells of this world go? Why don't we have more people like him today? Have they just been drowned out by idiots with access to a microphone?
A hundred years ago, Charles Kingsley described Science as “making nasty smells in a laboratory”. A year or two ago a young industrial chemist informed me, smugly, that he “could not see what was the use of poetry”. So the pendulum swings to and fro, but it does not seem to me that one attitude is any better than the other. At the moment, Science is on the upgrade, and so we hear, quite rightly, the claim that the masses should be scientifically educated: we do not hear, as we ought, the counter-claim that the scientists themselves would benefit by a little education. Just before writing this, I saw in an American magazine the statement that a number of British and American physicists refused from the start to do research on the atomic bomb, well knowing what use would be made of it. Here you have a group of sane men in the middle of a world of lunatics. And though no names were published, I think it would be a safe guess that all of them were people with some kind of general cultural background, some acquaintance with history or literature or the arts – in short, people whose interests were not, in the current sense of the word, purely scientific.
Irony Upon Irony
For those (few) of you who are interested in the pathology of IDiots, you have to read Irony of the Day. It's posted on Uncommon Descent and the author is Barry Arrington.
This is a satirical summary of his point.
This is a satirical summary of his point.
Many skeptics say that the Flying Spaghetti Monster is imaginary. However, it's impossible to prove that the Flying Spaghetti Monster doesn't exist. Even Richard Dawkins says that you can't prove a negative.You can't make this stuff up.
Therefore, when you say that the Flying Spaghetti Monster is imaginary, you aren't being a true skeptic. Instead, you are expressing "uncritical arrogant dogmatism that would make the most committed fundamentalist blush. And that, my friends, is the irony of the day."
Reviews of Darwin's Doubt: Keeping Score
Several scientists have reviewed Stephen Meyer's latest attack on science [see Slaying Meyer’s Hopeless Monster]. Don't think the IDiots haven't noticed ... they've responded to several specific criticisms (and ignored others).
I know it's hard to keep score so David Klinghoffer has done it for us in: More Evidence of Darwinian Short-Term Memory Loss.
I know it's hard to keep score so David Klinghoffer has done it for us in: More Evidence of Darwinian Short-Term Memory Loss.
As far as I'm aware, no reviewer has yet genuinely laid a hand on "Darwin's Doubt," not for lack of trying. Well, there's always tomorrow.The IDiots are learning to master the basic skills of propaganda and they're doing a pretty good job. For example, here's a video promotion of Darwin's Doubt. See if you can recognize the lies, the tricks and the deceptions.
Monday's Molecule #214
Last week's molecule was 6-phosphogluconate, the second intermediate in the pentose phosphate pathway. Nobody got the right answer! [Monday's Molecule #213].
Classes have now started at most universities in North America so let's celebrate by picking a very simple molecule—one that most undergraduates should recognize if they've taken a biochemistry course. Derivatives of this molecule are essential components of several fundamental pathways; which ones? Give me the common name and the official IUPAC name.
Email your answers to me at: Monday's Molecule #214. I'll hold off posting your answers for 24 hours. The first one with the correct answer wins. I will only post the names of people with 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 email message.)
Classes have now started at most universities in North America so let's celebrate by picking a very simple molecule—one that most undergraduates should recognize if they've taken a biochemistry course. Derivatives of this molecule are essential components of several fundamental pathways; which ones? Give me the common name and the official IUPAC name.
Email your answers to me at: Monday's Molecule #214. I'll hold off posting your answers for 24 hours. The first one with the correct answer wins. I will only post the names of people with 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 email message.)
Friday, September 06, 2013
Darwin's Doubt: The Genes Tell the Story?
The main goal of Intelligent Design Creationism is to cast doubt on modern science, especially evolutionary biology. Most of the IDiot books are devoted to attacks on evolution. The underlying assumption is that if modern science is discredited then "god-did-it" becomes a viable alternative.
The latest book by Stephen Myer is no exception. The theme is that evolutionary biologists cannot explain the Cambrian Explosion; therefore, God must have created all the animals in the space of a few million years back in the Cambrian Era (about 530 million years ago).
Most of the book is about the lack of transitional fossils that document the slow transition from primitive worm-like creatures to modern phyla such as arthropods and chordates. Others have dealt with this and I'm not going to comment because it's outside of my area of expertise.1
There is strong evidence from molecular evolution that the major animal phyla share common ancestors and that these common ancestors predate the Cambrian by millions of years. In other words, there's a "long fuse" of evolution leading up to the Cambrian Explosion. Meyer refers to this as the "deep-divergence" assumption.
There are many versions of these trees. The one shown here is from Erwin et al. (2011). It's the one shown in the book The Cambrain Explosion by Douglas Erwin and James Valentine. It isn't necessarily correct in all details but that's not the point.
The point is that molecular phylogenies demonstrate conclusively that the major groups of animals share common ancestors AND that the overall pattern does not conform to a massive radiation around 530 million years ago. Also, it's very clear that the pattern is consistent with evolution and not with God creating all the animals at once.
Stephen Meyer has to address this evidence because it casts doubt on his main theme (God did it). I suppose I don't need to tell you what he says ... it's typical creationist denial. He claims that the evidence doesn't exist. Here are his reasons ...
The latest book by Stephen Myer is no exception. The theme is that evolutionary biologists cannot explain the Cambrian Explosion; therefore, God must have created all the animals in the space of a few million years back in the Cambrian Era (about 530 million years ago).
Most of the book is about the lack of transitional fossils that document the slow transition from primitive worm-like creatures to modern phyla such as arthropods and chordates. Others have dealt with this and I'm not going to comment because it's outside of my area of expertise.1
There is strong evidence from molecular evolution that the major animal phyla share common ancestors and that these common ancestors predate the Cambrian by millions of years. In other words, there's a "long fuse" of evolution leading up to the Cambrian Explosion. Meyer refers to this as the "deep-divergence" assumption.
There are many versions of these trees. The one shown here is from Erwin et al. (2011). It's the one shown in the book The Cambrain Explosion by Douglas Erwin and James Valentine. It isn't necessarily correct in all details but that's not the point.
The point is that molecular phylogenies demonstrate conclusively that the major groups of animals share common ancestors AND that the overall pattern does not conform to a massive radiation around 530 million years ago. Also, it's very clear that the pattern is consistent with evolution and not with God creating all the animals at once.
Stephen Meyer has to address this evidence because it casts doubt on his main theme (God did it). I suppose I don't need to tell you what he says ... it's typical creationist denial. He claims that the evidence doesn't exist. Here are his reasons ...
- There are no fossils to support the earliest branches in the molecular phylogenies.
- There are many different molecular trees and they don't all agree with each other in terms of branching order and timing.
- Evolutionary biologists cherry-pick the data by only picking molecules that give reasonable trees.
- The trees rely on questionable assumptions; namely, that the molecular clock ticks at a constant rate and that there is a universal tree.
- The molecules being compared must be homologous but this is what is being tested so the argument is circular.
Comparative genetic analyses do not establish a single deep-divergence point, and thus do not compensate for the lack of fossil evidence for key Cambrian ancestors—such as the ur-bilateran or the ur-metazoan ancestor. The results of different studies diverge too dramatically to be conclusive, or even meaningful; the methods of inferring divergence points are fraught with subjectivity; and the whole enterprise depends on a question-begging logic. Many leading Cambrian paleontologists, and even some leading evolutionary biologists, now express skepticism about both the results and the significance of deep-divergence studies.I'm hoping to find time to go over each of Meyer's objections since they reveal a lot about IDiot misconceptions of evolution (and science) and a lot about how they employ strawmen, lies, quote-mining, and distortions in order to discredit an entire field (molecular evolution).2
1. Most IDiots are experts in everything. I'm not as smart as they are.
2. It always amazes me to discover that IDiots like Stephen Meyer think they know more than thousands of expert biologists who do this sort of stuff for a living.
Erwin, D.H., Laflamme, M., Tweedt, S.M., Sperling, E.A., Pisani, D. and Peterson, K.J. (2011) The Cambrian conundrum: early divergence and later ecological success in the early history of animals. Science 334:1091-1097. [doi: 10.1126/science.1206375]
Goodbye Women's College Hospital
My son was born in this building 35 years ago. It will look very different when the destruction/construction is complete (Women's College Hospital).
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