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.
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.
In a previous post I mentioned an article by Sidneyeve Matrix who advocates changing the "traditional" form of undergraduate university education by incorporating more technology [Challenges, Opportunities, and New Expectations]. In that post, I concentrated on one of the arguments for online courses [On the Quality of Online Courses].
In this post I want to bring up one of the arguments for introducing new technology into a course. I'm going to pick a quote from Sidneyeve Matrix's article but she's not the only one who brings it up.
There’s a torrent of research demonstrating the costs and benefits of using social, mobile, and digital technology enhancements to teach; yet it’s inconclusive whether these result in higher student outcomes. Of course, there are multiple bottom lines to consider. What’s undeniable is that even though digital divides exist, today’s students expect to see some technology used in their classes. It follows that we can expect increased engagement and higher student satisfaction when profs power-up. In my experience, exceedingly positive end-of-term student surveys and reviews in my ed-tech enhanced courses document a beneficial halo effect.
The first statement is true, as far as I know. There are no sound pedagogical reasons for incorporating social media and other technologies into a course. That means there must be other, not-pedagogical, reasons for change.
The third statement says that it's "undeniable" that students expect to see some technology in their class. What does this mean? Will they be satisfied if they see a power point presentation and a website? Do they expect their professors to befriend them on facebook or follow their tweets? We don't know. The statement is devoid of meaning.
However, what seems to be "undeniable" is that there are some professors who think that it's important to give students whatever they want. These professors seem to think that it's the students, not them, who are the experts on undergraduate education. Is there any evidence for that?
Of course not. The reason for giving students what they want is clearly spelled out in the last sentence. If you give them what they want then you'll get good student evaluations.
In fairness, she also mentions "engagement." If student engagement is one of your goals—it's one of mine—then that's a reason for exploring technology options. That may, or may not, be associated with student satisfaction. My experience suggests that it's not. I first started an online discussion forum for students in 1987-88 using a usenet forum running on a VAX. Very few students used it but the ones who did liked it a lot.
Over the last 25 years, I've tried various ways of encouraging student engagement on the internet including, in the last iteration, trying to get students to read and comment on blogs. The result is always the same. A subset of the class has a great time "engaging" and a larger subset resists all attempts to draw them in. The most effective way to encourage, and reward, engagement is to do it in class with the students right there with you. The downside is that a good chunk of your class are miserable because they don't want to "engage" in their own learning. They would rather be passive learners.
In order for professors to engage in podcasting or online lectures or tweeting, or supporting their colleagues who opt to publish in open source journals or participate in online conferences, they must see real benefits and an immediate, significant return on investment. Perhaps for some profs evidence of increased student satisfaction and engagement will win them over.
I hope that "increased student satisfaction" will never be a primary motive for change. It may be a secondary benefit but that's not the same thing. Our job is to teach effectively. If the proper teaching methods don't "please" the students then our job is to convince them that they need to change their minds about what gives them pleasure. If they can't do that then they might have only two choices: (1) be miserable throughout their stay in university, or (2) drop out.
Option three: (3) make the professor change the course in order to cater to the student's view of how a course should be taught, is not a reasonable option.
Many of these debates and discussions about the use of new technology in the classroom assume that there's resistance from old professors who are uncomfortable with new technology and/or social media. That may be true of some professors but many of my mature colleagues have been computer literate since before many young professors were born. Many of my colleagues have been using email for thirty years. They have had webpages, including course webpages, since the web was created twenty years ago. In spite of the fact that they are not intimidated by technology—what science professor is intimidated by new technology?—they have not radically transformed their way of teaching in the past several decades. Why is that? Is it because they have the wisdom and experience to know that new technology is not the best way to improve undergraduate education?
Are online courses a good thing, a bad thing, or relatively neutral? There's much to debate.
The main issue, as far as I'm concerned, is pedagogical. Are online courses a good way to teach critical thinking—the primary goal of undergraduate education?
There are tangential issues that often get in the way of dealing with the important questions and I'd like to deal with one of them here.
In a previous post [Is Canada Lagging Behind in Online Education?] I criticized a newspaper article by Michael Geist because he made an incorrect assumption. He assumed that any online course from a "top-tier" university would be serious competition for the average Canadian school. I selected two courses from MIT and showed that the quality of their biochemistry teaching was not a threat.
This point needs to be emphasized. Just because an online undergraduate course comes from Harvard, MIT, or Stanford does not mean that it's a good quality course. In my own field of biochemistry I know of many, many teachers in small schools throughout North America who can teach biochemistry better than famous research professors at the so-called "top-tier" schools.
It still may be true that students will flock to the Harvard, MIT, and Stanford courses and pay those schools for biochemistry credits but let's not assume, without justification, that they are getting a better education.
Today I received a copy of Academic Matters: OCUFA's Journal of Higher Education, a magazine published by the Ontario Federation of University Faculty Associations (OCUFA). The articles are devoted to technology in the classroom ("Professor 2.0." ugh!). An article by Sidneyeve Matrix [Challenges, Opportunities, and New Expectations] caught my eye. She says,
When Stanford University offers massively open online courses (MOOCs) in science and engineering, in one case drawing over 150,000 participants, people take notice. When the Khan Academy wins significant Microsoft funding, posts 3,000 instructional videos online, and attracts massive traffic, stories proliferate about the future of self-directed, online, informal e-learning. ... Critics ask, what’s the value of having students attend a lecture in real time if essentially the same material is covered by world-renowned professors on professional-quality video courtesy of free services at TED-Ed or YouTube Education? ... Why pay enormous fees to learn from faculty in an accredited university program, when MITx offers free online courseware with options for students to get peer-to-peer and professor feedback, assessment and earn branded certificates of achievement? What is the return on investment for students (and perhaps their parents) opting to earn their credentials at a bricks-and-mortar university when they could join the 30,000 others enrolled at the London School of Business and Finance in their Global MBA program—delivered online via a Facebook app?
There's a myth here that needs exposing. The quality of undergraduate education in the sciences1 should be judged by the content of the course and not the prestige of the university that offers it. Let's not get bamboozled into thinking that just because Stanford and Khan University Academy offer an online course in biochemistry that it's necessarily a good course.
The MIT examples I highlighted in my previous post says that this is a a bad assumption. You can look at the Stanford University Courses and make up your own mind.
Here's the important point: don't just assume that because an online course exists, it is necessarily a good course. You may have legitimate reasons for thinking that online courses are good things, but that doesn't excuse you from actually looking at the quality of an online course before declaring that the producers of such a course did a good job. Putting a bad course online is worse than putting no course online no matter what you might think of online courses.
1. I restricted myself to the sciences because we are presumably judging quality by the ability to teach critical thinking and factually correct material. There may well be degrees and programs where this isn't important. For example, it may not be important who teaches MBA courses since the goal is just to get a degree to put on your CV. In that case the prestige of the London School of Business and Finance may be far more important than whether you are actually learning something useful, or correct.
The author is Michael Geist who is described as follows ...
Michael Geist is a law professor at the University of Ottawa where he holds the Canada Research Chair of Internet and E-commerce Law. He has a Bachelor of Laws degree from Osgoode Hall Law School in Toronto, Master of Laws degrees from Cambridge University in the UK and Columbia Law School in New York, and a Doctorate in Law from Columbia.
Hmmm ... that's interesting. A lawyer with no obvious expertise in education is writing about education. Let's see what he has to say ...
... in recent weeks it has become increasingly clear that the future of education is here, though it is not evenly distributed. The emerging model flips the current approach of expensive textbooks, closed research, and limited access to classroom-based learning on its head, instead featuring open course materials, open access to scholarly research, and Internet-based courses that can simultaneously accommodate thousands of students. The concern is that other countries are becoming first adopters, while Canada lags behind.
Here's an interview with Don Tapscott where he tells us what's wrong with universities and why they need to become more student focused [The future of education: reboot required]. The main theme is that today's students are wise in the ways of the internet and that will force universities to change.
I think the net generation will be a key driver for change. They have the knowledge and tools to challenge the existing model, and I see a growing generational clash.
I also think some administrations will recognize that the writing is on the wall.
If students can pass a course by never attending class and watching the lectures online, why should the student be restricted to only those courses available at that university? If it's online, why not choose from the courses offered at other universities. I also see a lot of the old guard faculty retiring soon. That will help generate fresh thinking.
There are several issues in this debate. They need to be sorted and clarified. First, many of the "old guard" faculty are among those who are most upset with the current system. At my university, they are the ones who are advocating change. Younger faculty in science departments just don't care about undergraduate education. They have much more important things on their minds. The situation isn't much different in the humanities except that there's a somewhat higher percentage of younger faculty calling for change. Many of them are postmodernists and the changes they're advocating aren't necessarily desirable.
Who is Don Tapscott and why is he an expert on university education? Here's what Wikipedia says [Don Tapscott].
Don Tapscott (born 1947) is a Canadian business executive, author, consultant and speaker based in Toronto, Ontario, specializing in business strategy, organizational transformation and the role of technology in business and society. Tapscott is chairman of business strategy think tank New Paradigm (now nGenera Insight), which he founded in 1993. Tapscott is also Adjunct Professor of Management at the Joseph L. Rotman School of Management, University of Toronto.
This brings me to a second point that needs clarification. People whose main concern is business and management aren't necessarily qualified to have an informed opinion on university education. That includes 99% of the faculty at the Rotman School of Management, here at the University of Toronto.
The third point that needs to be made is that there is widespread agreement that current university education is in bad shape. It should not be possible to skip lectures and still get an "A" in a course. It should not be possible to graduate with a degree when you have never physically attended a university. The fact that we are doing a bad job of teaching students how to think does not mean that we should abandon that goal and make it even easier for students to avoid intellectual challenges. We need to fix the problem, not surrender.
The fourth point concerns technological change. Tapscott is apparently one of the true believers when it comes to the internet and how it's going to change everything. I think he's wrong but that's not the point I want to make. The thing that annoys me the most is the assumption that universities are behind the times when it comes to technological change and that professors are luddites who don't know anything about computers and the internet.
There may be professors like that, but not in science or engineering departments. I suspect that they're rare in the humanities as well. This may come as a bit of a shock to Don Tapscott but some of us old fogies have been using computers for over forty years. We've been on the internet for thirty years. We know about electronic databases, listserves, social networks, webpages, and blogs. Some of us even have cellphones, iPads, and GPS—and we know how to use them. We have HD televisions, stereo systems that will blow your socks off, laptops, and—believe it or not—power windows in our cars.
We've been incorporating these technologies into our courses for over two decades. (That's before our entering class of students was born.) Our children, and the current crop of students, may be the first generation to grow up with personal computers and the internet but when they come to university they will be meeting the generation that invented those technologies.
Give us a bit of credit. We've been experimenting with new technologies long enough to know how they are affecting university education. We are not stupid. If they were capable of totally transforming university education then we would have discovered that by now. Fact is, these technologies have been around for decades and, while they are very useful supplements to education, they are not a panacea and they cannot replace everything that happens on a university campus.
Students need to be provoked, challenged, and stimulated. They need to be thrust into an environment that's outside of their comfort zone. They need to hear things they don't want to hear, even if it makes them angry. They need to see for themselves what kind of scholarship goes on at a university. They need to do a research project and that requires a mentor.
They need to meet graduate students and postdocs and professors who aren't teaching one of their courses. They need to play varsity sports, join the debating team, attend meetings of the student Secular Alliance, meet students from different cultures, protest, volunteer at the local hostel, play in the school orchestra.
This is all part of a university education and you can't do it by sitting in your bedroom at home staring at your monitor.
The article on the CBC News site makes reference to two videos. I'm including them here in order to provoke discussion. The first one is a classic example of the kind of superficial thinking that passes for knowledge among today's generation of students. Although that's not its intent, it illustrates perfectly what's wrong with university education. There's no evidence of critical thinking. The students are holding up sound bites of meaningless phrases.
The second one is similar except that the students are much younger. It's an example of brainwashing. They are "digital learners"—but what the heck does that mean? It doesn't mean a damn thing.
The other day I was discussing how to teach evolution with one of my colleagues and the discussion turned to the presumed distinction between students who were really interested in science and everyone else. My colleague claimed that students who were science oriented probably managed to acquire a good understanding of evolution in spite of the fact that some undergraduate courses weren't doing a very good job of teaching the subject.
I pointed out that my impression was different. I suggested that most Professors in our department don't have a firm grasp of one of the most fundamental concepts in biology (evolution), and neither do our graduate students. I reminded my colleague of the times when we cringe at graduate student presentations when the topic of evolution comes up.
Ryan Gregory must have felt the same way since he was prompted to do a survey of graduate students in science departments at Guelph University. The result is published in BioScience. You can read about it on Ryan's blog: How well do grad students grasp evolution?. Here's the press release...
Science Students Could Brush Up On Darwin, U of G Study Finds
October 01, 2009 - News Release
Even students pursuing advanced degrees in science could brush up on their knowledge of evolution, according to a new study by University of Guelph researchers.
The finding reveals that there is room for improvement in how evolution is taught from elementary school up, said Ryan Gregory, a professor in Guelph’s Department of Integrative Biology, who conducted the research with former student Cameron Ellis.
The study was published today in BioScience. It’s particularly timely, given that this year is the bicentennial of Charles Darwin’s birth and the 150th anniversary of publication of On the Origin of Species, which underpins understanding of the diversity of Earth’s organisms and their interrelations.
“Misconceptions about natural selection may still exist, even at the most advanced level,” Gregory said.
“We’re looking at a subset of people who have spent at least four years, sometimes even six or seven years, in science and still don’t necessarily have a full working understanding of basic evolutionary principles or scientific terms like ‘theories.’”
Many previous studies have assessed how evolution is understood and accepted by elementary, high school and undergraduate students, as well as by teachers and the general public, Gregory said. But this was the first to focus solely on students seeking graduate science degrees.
The study involved nearly 200 graduate students at a mid-sized Canadian university who were studying biological, physical, agricultural or animal sciences. About half of the students had never taken an evolutionary biology course, which is often not a prerequisite.
The researchers found that the vast majority of the students recognized the importance of evolution as a central part of biology. Overall, they also had a better understanding of evolutionary concepts than most people.
“That was encouraging, especially because it was across several colleges — it wasn’t just the biology students,” Gregory said.
But when the students were asked to apply basic evolutionary principles, only 20 to 30 per cent could do so correctly, and many didn’t even try to answer such questions. Of particular interest to Gregory is the finding that many students seem less than clear about the nature of scientific theories.
“This is telling us that traditional instruction methods, while leading to some basic understanding of evolution, are not producing a strong working knowledge that can be easily applied to real biological phenomena.”
Gregory has studied evolution-related topics for years and recently co-organized a workshop designed to improve how the subject is taught in public schools. He is also associate editor of Evolution: Education and Outreach, a journal written for science teachers, students and scientists. He recently created Evolver Zone, a free online resource for anyone interested in evolutionary biology. He is also helping bring an evolution-inspired art exhibit to U of G this month. “This View of Life: Evolutionary Art in the Year of Darwin, 2009” highlights diverse artists’ views of Darwin’s ideas and evolution in general. It runs Oct. 9 to 30 in the science complex atrium.
Some of us know what the problem is. What are we going to do about it? How are we going to convince professors that evolution education has to change when most of them don't even recognize there's a problem because their own views of evolution are flawed?
The University of Vermont will be awarding an honorary degree to Ben Stein, the man behind the movie Expelled. Here's the press release from the University of Vermont [Ben Stein to Deliver Commencement Address]. Notice that they don't mention the movie. That's no excuse.
The multi-talented Ben Stein, actor/comedian/lawyer/economist/presidential speechwriter/filmmaker, will address the graduates and receive an honorary degree at the University of Vermont's 205th commencement ceremony on Sunday, May 17.
Popularly known as the host of Comedy Central's seven-time Emmy award winning game show, "Win Ben Stein's Money," and for an iconic classroom scene in the film Ferris Bueller's Day Off, Stein is also an accomplished writer who has published 30 books and written for publications ranging from the Wall Street Journal and The New York Times to E! Online and New York Magazine. Stein earned his undergraduate degree with honors in economics from Columbia University and went on to graduate as valedictorian of his class from Yale Law School. He has taught at American University, the University of California at Santa Cruz and Pepperdine University in subjects ranging from political and social content of mass culture to securities law. Along with his academic and entertainment achievements, Stein has as served as a trial lawyer for the Federal Trade Commission and as White House speechwriter for presidents Nixon and Ford.
The University of Vermont offers a Major in Biochemistry. Before enrolling, students need to check out the courses to see if they encourage critical thinking and to see how evolution is presented.
The University of Vermont has every right to award honorary degrees to anyone they want. That's what academic freedom is all about. The downside is that the University of Vermont will be judged by who they choose to get an honorary degree. That judgment is not going to be favorable.
UPDATE: Ben Stein has decided that he has another commitment that will prevent him from receiving the honorary degree from the University of Vermont [Stein backs out].
Having been involved in selecting honorary degree recipients, I can assure everyone that you don't make public announcements until the candidate has agreed. Thus, it looks very much like Ben Stein and the university have made a joint decision that inviting Stein to accept an honorary degree was a mistake.
I'm glad the University of Vermont came to its senses.
However, it's fair to say that Lipmann made some of the most important contributions to our understanding of ATP as an energy currency. His classic 1941 paper in Advances in Enzymology was entitled "Metabolic Generation and Utilization of Phosphate Bond Energy." In that paper he introduced the concept of an energy-rich phosphate bond designated by a squiggle (~). Thus ATP could be represented as
AMP~P~P
to show that it had two such high energy bonds. The cleavage of either bond is accompanied by a large release of energy that's available to do work. The idea that ATP contained some special bonds with high energy was very attractive and the concept ruled in biochemistry textbooks for several decades. Indeed, there are still many courses and websites that still use the squiggle.
The concept is extremely misleading and came under attack by many biochemists in the 1950s and 60s. According to these biochemists, the correct way of looking at ATP as an energy currency is to recognize that the overall reaction of hydrolysis is associated with a large negative Gibbs free energy change.
ATP + H2O → ADP + Pi ΔG°′ = -32 kJ mol-1
It's the system, including reactants and products, that is associated with the large negative free energy change. The only reason ATP is useful as an energy currency is because the concentration of ATP is maintained at high levels relative to ADP + Pi inside the cell. As a matter of fact, the actual Gibbs free energy change in vivo is closer to -48 kJ mol-1.
If the system were allowed to reach equilibrium then ΔG°′ = 0. Think about what this means. At equilibrium those ~P "high energy" bonds are still being broken but there's no useful energy being produced.
Does this mean that the strength of a chemical bond depends on the relative concentration of reactants and products? Of course not. What it means, in the words of someone who knew Friz Lipmann, is that his understanding of basic thermodynamics was rudimentary.
The arguments over the proper way to think about ATP raged back and forth in the scientific literature for over thirty years. For the most part Lipmann did not participate in the squiggle debates, he left his defense to others. It's fair to say that there was no knock-out blow that ended the fight. Gradually people began to realize that the squiggle—and the concept of a high energy bond—were unfortunate at best and possibly misleading to the point of being counter-productive. The squiggle has been dropped from most (all?) textbooks.
So, how do we explain the fact that ATP hydrolysis is associated with a large release of energy under conditions found inside the cell? If it's not because of some special "high energy" bond, then what is it? See Why Is ATP an Important Energy Currency in Biochemistry?.
Here's a couple of articles on the history of the squiggle:
Here are some websites that still refer to "high-energy" bonds and still use the squiggle. It's interesting that most of these sites include a modest disclaimer, stating that there's no such thing as a "high-energy bond" but they then go on to talk about high energy bonds using the squiggle notation.
[I am indebted to my colleague Byron Lane for explaining the history to me. He was a post-doc in the Lipmann lab during the 1950s where he was in a position to observe the debate first-hand. Byron kindly gave me copies of the relevant papers. Our discussion began when we realized that the kinds of scientific debates that were common in the past are no longer occurring even though there are many controversies bubbling beneath the surface. We don't know why. Does anyone?]
Eva Amsen has an article in this week's issue of The Bulletin—the newspaper published by the University of Toronto (not a student newspaper). You can read her description of how this article came to be published by checking out her Nature network blog [Teaching course and article on OpenCourseWare]. The article is online at The Bulletin. Scroll to the last page.
The article is about OpenCourseWare in general, and the MIT experiment in particular. MIT, and a few other schools, have made a commitment to put course material on a website and make if freely available to anyone who wants to use it. All one has to do is follow the guidelines of the Creative Commons License. MIT retains the rights to the material even though students and other lecturers are free to use it. MIT strips out all material that is copyrighted by third parties; this includes textbook figures and photographs and images taken from other websites. According to the MIT OpenCourseWare Website, it costs between $10,000 and $15,000 to publish each course. The costs will be twice as high if videos of the lectures are posted online.
Eva's article mentions some of the benefits of OpenCourseWare. Not all of them are believable; for example, one third of freshman students claim to have chosen MIT because they were influenced by OpenCourseWare. This probably doesn't mean what one might think.
Eva is a graduate student in our department so she asks, "Why is the the University of Toronto, one of Canada's leading universities, not part of the OpenCourseWare Consortium?" I'd like to address that question, making particular reference to biochemistry courses.
Let's begin by looking at the OpenCourseWare site for the Department of Biology (MIT doesn't have a Biochemistry Department) [Biology].
The first thing you notice is that most of the material is quite old. Some of the courses are from 2004, only one is 2007, and none are 2008. Let's check out the Spring 2006 course in Introductory Biology to see what OpenCourseWare is really like. Two clicks take you to complete audio lectures. You can listen to the lectures or read a transcript of the lecture. There is no supplemental material to speak of and no figures to see. I don't find this very helpful.
Contrast the MIT website with a typical university website like ours at the University of Toronto. We have more than 2000 course websites but the vast majority are restricted to University of Toronto students [Course Catalog]. If you could access the introductory biology course you would find complete powerpoint lectures with all figures and plenty of additional course material. All of it is up to date.
In some department the course material is not password protected [Dept. of Biochemistry] but it is not advertised and outsiders are not encouraged to visit the site. Complete lecture notes with figures are made available to the students. In my opinion, these notes are much more valuable to students taking our courses than the MIT OpenCourseWare lecture notes because we can post the figures without having to be wary of copyright infringement (especially if access is restricted).
Thus, one of the biggest downsides of OpenCourseWare is that the notes have to be stripped of figures. Why should our department go to great effort and expense to create a parallel site for external viewing when we know full well that the stripped down notes are practically useless? There has to be a compensating gain, right?
Eva argues that the gain is significant.
While the implementation of OpenCourseWare asks for extra work from its faculty in preparing high-quality, legally distributable course materials, this works as an incentive to produce better teaching materials. As a result, making course materials available online can not only raise an institution's visibility but also its quality.
I don't believe this for a minute. The quality of lecture material on the web is highly variable and the fact that it's freely available does not to seem to have much effect on quality. If the argument holds, we would expect the biochemistry lectures at MIT to be outstanding examples of high quality lectures.
Let's check it out. The introductory biology course from 2006 (the latest one on the web) has ten lectures on "foundations." Three of them are on biochemistry. The first one [Biochemistry 1] is all about cancer cells. The material is present at a high school level, at best. The second lecture (Biochemistry 2) is not available on the website. The third one [Biochemistry 3] is on enzymes. Here's how it begins ...
OK. So we’re going to continue with the discussion about biochemistry, and specifically focus on enzymes today. Professor Sive introduced those to you briefly in her last lecture. I’m actually covering for her today. This is one of her lectures but she has given me her material, so hopefully it will go fine. She wanted me to remind you a little bit about energetics, specifically that a negative Delta G in a reaction implies that the reaction can occur spontaneously, that is if the products have lower energy than the reactants. And so given enough time this will happen in that direction.
It's pretty much downhill from then on.
I checked out a lot of lectures on the MIT biology OpenCourseWare site and I don't see much evidence that the faculty has taken the time to prepare high quality lectures. Furthermore, if I had to evaluate the quality of teaching at MIT based on the OpenCourseWare, I don't think it would enhance the reputation of the university.
One of the main arguments for OpenCoureWare has been altruistic. The idea is that a really good university should make its lectures available to the world so that lecturers at "lesser" universities can copy it and use it in their classrooms (an argument that is also condescending). In my experience, the lecturers at smaller schools often give much better lectures in biochemistry than those at the big research intensive universities. If I'm looking for a really good textbook reviewer, for example, I'm much more likely to find one at the University of Maine or the University of Nebraska than at Harvard or Berkeley.
If every school puts up their stripped down versions of lectures, you can be assured that there will be some real gems out there. On the other hand, you can be certain there will be lots of garbage as well. OpenCourseWare may end up being just another way of cluttering up the web with useless information, or worse. If every school participates in the consortium, for example, you would probably find 100 incorrect definitions of a gene, or the Central Dogma, and 100 false conception of free energy at the top of your Goggle search. What's the point of promoting that?
Do you want to learn about enzymes on the web? Here's where you go to get free and accurate information from people who know what teaching is all about [Enzymes] [Enzymes] [Enzymes] .
This is a post about the quality of science writing and what can be done about it. I'm picking on an article in SEED magazine here but it's not because SEED is any worse than the competition. It's partly because SEED makes claims about raising the quality of science writing and science education. For example, this statement from a SEED press release seems to indicate that they aspire to better science writing than the competition [Seed Media Group Adds Scientific and Political Pundits to Editorial Team] and certainly their commitment to science bloggers suggests the same aspiration.
As part of its growth strategy, Seed Media Group will develop original science content aimed at a general audience for distribution across a number of media channels, including magazines, books, newspapers, online, topical blogs, digital, film and television. Seed Media Group's endeavors will present science in the same culturally articulate and accessible style that earned Seed a prestigious UTNE Independent Press Award in 2004 and the support of leading advertisers.
It's reasonable, in my opinion, to expect that SEED will live up to this billing. They've certainly made a major step in that direction by hiring PZ Myers to write a monthly science column. The science in his first two contributions is impeccable. As we will see, it raises the question of whether you need to be a scientist in order to get the science right. I hope that's not true.
I'm not going to criticize PZ's articles. Instead, I want to examine another article published in the March 2007 issue of SEED. (That's the one with the "TRUTH" prominently displayed on the cover!) The article in question is titled The Sound of Silence and it's written by Lindsay Bothwick, an experienced science writer with a M.Sc. from McGill and a Masters degree in journalism from Ryerson University here in Toronto. She's a senior editor at SEED so I'm assuming she can take criticism.
The article talks about silent mutations in protein-coding regions. The focus is on a recent Science paper showing that some silent mutations affect the activity of a protein. The point I will make is that the SEED article is very misleading and misrepresents the state of knowledge in this field.
Before getting into the article, let me give you some background.
The most common kinds of mutations are those where one nucleotide is substituted for another. For example, a G or an A or a T replaces a C. This substitution usually results from an error during DNA replication.
If the mutation (allele) persists in a population, it's called a single nucleotide polymorphism or SNP (pronounced snip). The term polymorphism means that there are at least two different alleles segregating in the population. Often these are the original "wild-type" allele and the new mutant allele.
We now recognize that genomes within a population are very heterogeneous. Polymorphism is common. This level of variation was discovered in studies during the 1960's and it's much higher than most scientists thought prior to 1960.
There are three explanations that can, in theory, account for this high level of polymorphism
First, if we think about SNP's, they can represent a transient phase of fixation by natural selection. In this case, one of the alleles is rapidly replacing the other and we just happen to catch it in the act. Back in the days when natural selection was the only game in town it was thought that this transient stage would be rare so populations were not expected to show much variation.
Polymorphism can also be explained by balancing selection. This is when the population has to maintain several different alleles because there is selection for heterogeneity. The classic example is the mutation for sickle cell anemia. When a person is homozygous for the mutant allele they exhibit the symptoms of anemia but when heterozygous they are resistant to malaria. Balancing selection is not common and it can't explain the variation that was discovered in the 1960's.
The third explanation was that the variation is mostly neutral. The idea here is that the majority of mutations are not being acted upon by natural selection. They are not being removed by purifying selection; they are not being maintained by balancing selection; and they are not rising to fixation under positive selection. It was the discovery of significant polymorphism in populations that gave rise to Neutral Theory in the first place ((Kimura, 1968, King and Jukes, 1969).
Neutral mutations will eventually become fixed or be eliminated from the population and the change in frequency is due entirely to random genetic drift. Drift is a much slower process than natural selection so there will always be large numbers of neutral alleles in the process of becoming fixed or extinct.
Neutral Theory and random genetic drift explains variation and it also explains molecular evolution and the (approximate) molecular clock. There are no other explanations that make sense and nobody has offered a competing explanation since Motoo Kimura (1968) or Jack King and Thomas Jukes (1969) published their papers almost fifty years ago. (Aside from occasional nitpicks, of course. There are always scientists who like to show that some mutations that were thought to be neutral are actually beneficial or deleterious. None of them have mounted a serious claim that most variation or most of molecular evolution can be explained by natural selection.)
The history of variation and the competing explanations were well covered by Lewontin in his 1974 book The Genetic Basis of Evolutionary Change. (Lewontin published the classic 1960's papers that revealed extensive within population variation.)
Long-held assumptions about "silent" genetic mutations have been torn down, challenging a fundamental evolutionary theory.
Lindsay Borthwick SEED March 2007This brings me to the article in the March issue of SEED [The Sound of Silence]. It begins with a conclusion that's all too common in popular science writing these days,
Scattered throughout the human genome are thousands of mutations that biologists have treated mostly as footnotes. They're hardly few in number—in coding regions of the genome, there are as many as 15,000—but biologists regard them as mutations that simply don't change the way a cell functions. Both in name and effect, they have been accepted as "silent." Now, however, new discoveries are showing that silent mutations appear to play an important role in dozens of human genetic diseases, a fact that is forcing biologists to discard a long-held evolutionary theory and to reexamine the very rules governing the transfer of information from DNA to proteins.
What's going on here? Has there been some extraordinary new discovery that's about to overthrow evolutionary theory and the "rules" of information flow? I will attempt to show that this rhetoric is completely unjustified. It presents a misleading picture of the state of modern science.
The author is talking about silent mutations. These are mutations in the coding region of a gene that alter a codon without changing the amino acid. The genetic code is redundant because there are 64 possible codons and only 20 amino acids. This means that several amino acids have multiple codons. For example, there are six codons for leucine (Leu): TTA, TTG, CTT, CTC, CTA, and CTG. If an original TTA codon is mutated to CTA then it still specifies leucine and this is a silent mutation.
The concept of codon bias has been known for almost forty years and it's an important part of all university courses in molecular biology. Some codons are more efficient than others during translation because the levels of various tRNAs in a cell are not identical. A rare codon will be translated less efficiently because the tRNA that binds to it will not be recognized as frequently as the codon for more abundant tRNAs. There are published codon usage tables for most species showing the preferred codons in that species. Highly expressed genes will preferentially use the codons recognized by the abundant tRNA species. All students know what these tables mean. It means that not all silent mutations are neutral. (It's on the exam!)
This is only one possible reason for silent mutations not being neutral. The various possibilites were discussed by Jukes back in 1980 when he revisited the evidence for neutral changes (Jukes, 1980)) . He gave some specific examples and then addressed the theoretical problem,
The question arises, are these silent changes actually neutral, or have they taken place for adaptive reasons, such as the requirement for a specific secondary structure in mRNA, or a preferential use for certain transfer RNAs in regulating the rate of synthesis of a protein?
For some results the answer is that the silent changes really are neutral, although in a few cases there is evidence of adaptation. The point is that these issues have been recognized and dealt with for decades.
The existence of a few exceptions to a rule does not invalidate the generality. That's an important point. It's one that all science journalists need to grasp. There are no absolute, inviolate, rules in biology. The generalities are all about relative frequencies. Are most silent mutations neutral or are most subject to natural selection?
As Jukes put it 27 years ago,
The neutral approach to molecular evolution is a proposal to prove a negative, which is something like trying to show that a given substance is not a carcinogen. The counterrresponse to the publications by Kimura (1968) and King & Jukes (1969) has been quite strong. Any exceptions to neutrality are usually taken as disproof of it, and many authors have cited such exceptions for this purpose. We have, indeed, developed evidence for such exceptions ourselves, because a theory should be challenged by those who have postulated it.
For example, the finding that synonymous codons for each amino acid are not use in equal amounts in β-hemoglobin mRNA has been cited as disproof of the neutral model, as if such a departure from randomness in a single gene were pertinent.
As the old expression goes, "those who are ignorant of history are doomed to repeat it." It helps a lot to be aware of the history of biology and the contributions of those who developed our current understanding. Modern science writers often fail to understand that there's not much that's new in biology these days. In this case, it's just not true that biologists were too stupid to recognize that some silent mutations weren't neutral. There was no "orthodoxy" that all silent mutations were neutral and, therefore, no orthodoxy has been overturned.
Silent mutations have no impact on the amino acid sequence of proteins and, therefore, were not expected to change their function.
Lindsay Borthwick SEED March 2007The SEED article goes on to describe the results of experiments done by Kimchi-Safaty et al. (2007). They presented evidence that a cluster of three silent mutations in the MDR1 gene led to a slow down in translation and subsequent misfolding of the protein. Lindasy Bortwick then writes, "Through a series of elegant experiments, the team put to rest the idea that silent mutations were neutral." Of course, they did no such thing. They merely added one more data point to something that we already knew; namely, not all silent mutations are neutral.
Borthwick closes with,
Most fundamentally, the involvement of silent mutations in disease undermines the neutral theory of molecular evolution. This theory, posited by Motoo Kimura in the late 1960s and a powerful influence ever since, asserted that the vast majority of mutations were neutral, having no effect on the fitness of an organism, and spread through a population by chance. The fact that silent mutations are not harmless anomalies of nature means that they are not neutral. In contrast, some, if not all, silent sites must be subject to the forces of Darwinian natural selection.
The theme of the article is that neutral theory is in big trouble. This point is emphasized in the highlighted quotations that are prominently displayed on page 35 (see the two boxes above). That's totally wrong and it distorts the modern consensus among knowledgeable scientists. Neutral Theory is alive and well, thank-you very much. It can easily accommodate one more example of a non-neutral mutation.
I believe that science writers have an obligation to get the concepts right and I believe they shouldn't misrepresent the science they're supposed to be presenting in a "culturally articulate and accessible style" to a general audience. A layperson reading this article would go away with the impression that a decades old concept has just been overthrown by a single paper published in Science. That's irresponsible journalism.
Jukes, T.H. (1980) Neutral Changes Revisited. In The Evolution of Protein Structure and Function, pp. 203-219. . Lewontin, R.C. (1974) The Paradox of Variation. in Evolution Mark Ridley ed., Oxfrod University Press, Oxford UK.
Kimchi-Sarfaty, C., Oh, J.M., Kim, I.W., Sauna, Z.E., Calcagno, A.M., Ambudkar, S.V., and Gottesman, M.M. (2007) A "silent" polymorphism in the MDR1 gene changes substrate specificity. Science 315, 525-528.
Kimura, M. (1968) Evolutionary rate at the molecular level. Nature 217, 624-626.
King,J.L. and Jukes,T.H. (1969) Non-Darwinian evolution. Science 164, 788-798.
With a title like that how could you not want to read John Logsdon's new blog? Yesterday was his first post but I'm looking forward to lots more in the near future [Sex, Genes & Evolution].
John is a molecular evolutionary biologist in the Biology Department at the University of Iowa. He has published a number of papers with W. Ford Doolittle from the time he was at Dalhousie University in Nova Scotia. These include several papers with Arlin Stoltzfus on the evolution of introns. The Stoltzfus/Logsdon papers from this era were among the best papers to refute the intron-early hypothesis formerly championed by their mentor, Ford Doolittle. One of the things this demonstrates is that it's possible to disagree with your boss and survive!
Their chief target at the time was the Gilbert lab. John Logsdon was one of the participants in the famous online BioMedNet debate on The Origin and Evolution of Introns in November 1996—back in the time before blogs. This was mostly a debate between members of the Ford Doolittle lab and the Gilbert lab. Unfortunately, the transcript is no longer available. It was required reading in most molecular biology courses in the late 1990's. (I wish we had more debates like that.)
The Logsdon lab is interested in sex in protists, specifically the evolution of genes involved in recombination and meiosis (e.g., RAD51). John participates in a larger project that is trying to define the eukaryotic tree of life. As most of you know, the relationship of protists is controversial and the collaborative project intends to try and resolve the controversies. It not going to be easy to figure out the early history of eukaryotic evolution. This is a problem that has perplexed evolutionary biologists for several decades.
I'm excited about this project because they're looking at the best gene (HSP70). I hope he won't be disappointed to learn that my undergraduates have already solved the problem [The Evolution of the HSP70 Gene Family]. But all is not lost, those other genes might make a minor contribution to understanding evolution.
Welcome to science blogging, John.
Now, why not jump right in and describe your favorite hypothesis for why we have sex? I'm guessing you're a fan of repair, right?
