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Tuesday, April 13, 2021

How do you explain evolution to non-experts?

I spent a lot of time explaining evolution in my book. The goal is to educate readers to the level where they can understand the drift-barrier hypothesis and why slightly deleterious mutations can accumulate in species with small populations. This requires some knowledge of random genetic drift and some knowledge of Neutral Theory and Nearly-Neutral Theory. The emphasis is on population genetics as the most important way of understanding evolution.

You can't understand genomes and junk DNA unless you have a firm understanding of evolution. In fact, you can't make sense of anything about genes and gene expression without such knowledge ... what the heck, nothing in all of biology makes sense if you don't know about evolution.

My approach hasn't been copied by popular websites. They usually misrepresent evolution by presenting it as adaptation; natural selection is the only game in town. I'll put in a link to Francis Collins describing evolution in truly bizarre narration but my question for Sandwalk readers is whether this is useful or not. Is it better to dumb down evolution on the NIH: National Huamn Genome Website [Evolution] or is this a bad idea?


9 comments :

. said...

I'm an avid read of older popular science books, and one thing that stands out to me is that the authors expected more from their audiences back then. I still learn new things from older Asimov books and even Scientific American magazines from the 60s and 70s. I rarely enjoy modern popular science books as, in my opinion, current writers rely far too much on over simplistic analogies that don't fully describe the scientific concepts and often rehash the same material that has been covered many times over in other books. Similarly, many authors assume that their audience is incapable of looking up basic concepts that they may be unfamiliar with. This isn't limited to books either. There is quite a big difference between the older and newer approaches for science documentaries. In the classic science documentaries, such as the original Cosmos or The Ascent of Man, the viewers were treated as being willing to sit through a five minute monologue without a bunch of flashy graphics on the screen. Current documentaries rely far more on computer graphics and the science itself is usually presented in short sound bytes between the graphics. Even the tone bugs me, as I feel like the presenters are talking to an elementary school audience. This is even reflected in public heath announcements today, where it seems like they assume that the public is incapable of understanding nuance. I'm of the opinion that authors feel the need to dumb things down because few people these days even give them the chance to take on concepts that are a little more challenging.

To go back to your examples, it's not like your audience requires a PhD in biology to understands the basics of those concepts. I'm sure that you've used simple random sampling examples to demonstrate how genetic drift works for example. The mathematics of neutral theory can be pretty intimidating to someone without the proper education, but I don't think that the average person would have too much understanding the basics if they were taught that most mutations result in little to no phenotypic changes and the genomics data that supports the theory. One criticism of introductory genetics courses is that they focus too much on older concepts (eg mendelian genetics) and ignore newer ideas/methods. To an undergrad who wasn't taught about genomics, the idea of using DNA sequence data to see which parts of the genome are conserved might not come to mind.

To be honest, I don't think that the problems with evolution education are due to the concepts being too difficult to understand. Rather, I think that it comes down to ignorance. By ignorance, I mean that people are simple unaware of many of the concepts that you describe and are given misleading information by science writers or the scientists themselves. You've already made a pretty big case that many scientists are ignorant of concepts like junk DNA and haven't even bothered to read the older literature on these topics. Even the idea of reading the primary literature hasn't occurred to them. You could probably fill half your book with misconceptions propagated by scientists themselves.

You mentioned that your approach hasn't been copied by other websites. I would bet that this has more to due with exposure and that these authors aren't even aware that there are better approaches for science writing. If you decide not to dumb down these concepts, at least you'll stand out from all of the other writers who do so.

Larry Moran said...

I agree with everything you say and I've written about this extensively in my book. I'm waiting to see if the publisher will let me get away with it.

Over the past few weeks I've been discussing these issues with the author of a major educational website and his team. They tell me that the reason for presenting misinformation is because their audience (in this case it's health professionals) isn't smart enough to understand the real science.

It seems pretty clear to me that the real reason is because their team of biology PhD's had no idea that the information they were presenting was wrong. I think they are just hiding behind an excuse to cover up their own lack of understanding. I don't think they really believe me when I say that most of our genome is junk and that there's more to evolution than natural selection.

This confirms my suspicion that ignorance of these basic concepts is widespread even among people who should know better. (See my next post on alternative polyadenylation.)

Doug said...

I work in a medical lab and have an undergraduate degree and I love the information I get from your blog and the books you recommend (such as Michael Lynch's Origins of Genome Architecture). And I'm very much looking forward to reading your book.

Robert Byers said...

IF nothing could be understood about biology until evolution was accepted/understood then nothing was understood about bioilogy until Darwin! No one would agree with this I think. indeed biiology is easily understood based on biology as is. The origin story of how it got here is irrelevant to understanding what is here.
Evolutionism is irrelevant to biological sciences. Its only a history of biology processes and results. And is under suspicion for accuracy which is also why this blog exists.
I don't see why evolution is difficult to teach. its just the equation mutation plus mutation plus time equals results as seen.

Marcoli said...

What I say depends a lot on how much time I have, and on their background. But to undergraduates in my evolution class I get to the neutral theory of evolution on day 1, and later in the semester I work my way back to it as we wind our way through molecular genetics. When building those sessions, I surprised myself by how much time I allotted to the subject as it runs over quite a few class periods. In truth, this has been rather heavily influenced by your web site.

dean said...

"And is under suspicion for accuracy "

Every topic in science is constantly being studied -- "suspicion" is just the loaded phrase you choose to use.
Research goes on in physics, chemistry, and more: it's a feature of science.

There's nothing that your creationism bullcrap ads to knowledge in those areas, and nothing that has come from the "research" done by creationists.

Well, other than the fact that it identifies people like you who have no interest or ability in spending time to understand the real science.

"I don't see why evolution is difficult to teach."

I'm guessing you don't see a lot of things simply because you're too lazy to look.

Larry Moran said...

Sounds good. What I'm mostly concerned about is biochemistry and molecular biology students who don't ever take a course in evolution and are taught incorrectly by biochemistry and molecular biology professors who don't understand evolution.

What we need to focus on is convincing the majority of teachers that they need to upgrade their knowledge of evolution. I haven't been very successful at this, even in my own department, with one or two exceptions.

judmarc said...

I still remember what a damn relief it was when I graduated from high school and being taught about "valence" to college where I learned about quantum orbitals.

BS like "valence" doesn't help anyone because there's no "there there." As soon as anyone asks why or how it works that way, you're done, and you've lost all credibility.

Don't lie to people. That's not only not science, it's not common courtesy or basic persuasive technique.

Barbara said...

If people don't understand that random genetic drift and the neutral theory, they certainly won't ever understand junk DNA. It's totally appropriate to explain this in your book.