Pharyngula

Evo devo in the real world

I disagree with Razib Khan on a lot of things, but he’s exactly right on recent fads in biology.

Periodically I get frankly stupid comments that seem to imply that the incredible swell of results coming out of molecuar genetics and genomics are revolutionizing our understanding of evolutionary and population genetics. Over the past generation it’s been alternative splicing, then gene regulation and evo-devo, and now epigenetics is all the rage. The results are interesting, fascinating, and warrant deeper inquiry (I happen to see graduate school admission applications for genetics, and I can tell you that conservatively one out of three applicants mention an interest in epigenetics; the hype is grounded in reality, as epigenetics may be a pretty big deal in human health that we can effect).

All those phenomena he mentioned are real and often very interesting, but they’re not changing deep concepts in evolutionary biology. You’re most often going to hear that they’re revolutionary from people who don’t understand evolution very well.

He’s got a good assessment of evo devo, too.

There are some Christians who assert that their religion is the natural completion of Judaism and Greek philosophy.* There are others who rather argue that Christianity was a radical revolution against all that came before. Historically the latter has been a minority view. The Marcionites failed, and the Jewish origins of Christianity were sewn into the fabric of its foundational scripture in the form of the Old Testament. And despite periodic revolts, the reality is that intellectual Christianity speaks with a Greek philosophical voice. Ultimately this debate is of purely academic interest for me. But it exhibits a similarity with academic arguments and debates. In Endless Forms Most Beautiful: The New Science of Evo Devo
Sean B. Carroll takes a traditionalist approach which suggests that novel results from the new field of evolutionary developmental biology firmly supports and extends the Neo-Darwinian Synthesis. Carroll’s book is under 400 pages. It is elegantly written and economical of prose, and it proposes an evolution in our thinking about the nature of the variation which serves as the raw material for natural selection. Contrast that with the late Stephen Jay Gould’s The Structure of Evolutionary Theory, which came in at nearly 1,500 pages. Published in the early 2000s, much of it was written earlier. There are only two references to epigenetics within it. If Gould had not died in 2002 he would probably have come out with a new revised edition by now, and I’m rather confident that epigenetics would loom very large indeed. Though Sean B. Carroll is a very eminent scientist, he remains a bit player on the public intellectual scene. That’s because he does not promise revolution, he comes bearing a twist on the orthodoxy. In contrast, Gould’s prolix prose was rich with the promise of paradigms shattered and lost, and grand visions of heretics risen up to prophetic status, as the statues of the grand old men of the Neo-Darwinian orthodoxy were torn down to make way for the new idols (this old Paul Krugman slap at Gould is pretty on point about why he was so popular in the 1990s). Reality is more prosaic than intellectual revolts plotted in used bookstores!

I agree, except that I don’t think Krugman’s comments on Gould were that much on point. He dismisses punctuated equilibrium as wrong; it’s not. The problem with it is what Khan is saying here, that Gould took what should have been a good idea within the field of population genetics and puffed it up as revolutionary.

As for Carroll…yes, the big push in his evo devo book was for more recognition of the importance of regulation in evolution, which I think fits quite well within mainstream genetics. Some people seemed to bristle at the idea that cis regulatory elements could possibly be as important as coding genes, but they’re just cranky and wrong. I’ve also argued that evo devo is not revolutionary.

At least evo devo never was seized upon by creationists, like punctuated equilibrium (it’s hopeful monsters all over again! They just invented PE to leap over gaps in the fossil record!), nor was it rapturously embraced by New Age cranks, like epigenetics (You can change your evolution just by thinking about it!). I think that’s because most of evo devo’s proponents were fairly sober about presenting it as a facet of evolutionary theory, not a replacement for it.

Wait! I wrote that last paragraph and then realized that yes, there have been cranks touting evo devo. How could I have forgotten Susan Mazur and her Altenburg freak-out? And then I remembered Rupert Sheldrake and his morphogenetic fields. Nope, sorry, evo devo has suffered with its share of weirdos, too.

Comments

  1. #1 Jerry Standley
    Houston Texas United States
    December 29, 2015

    PZ, Reading this article reminds me of why I do not like
    journalists. The only thing they are good at is throwing
    a lot of words around without saying anything.
    Congratulations to you on that accomplishment.

  2. #2 See Noevo
    December 30, 2015

    There’s little, if any, “real world” about evolutionary developmental biology.

    It’s about as “real world” as unicorn biology.

    The only difference is that, with the former, a lot more people actually get paid to write about it. Creative writing more appropriate for an English Lit Department, with zero impact on actual science, medicine, or technology.

  3. #3 Buck Field
    Patagonia
    December 30, 2015

    “Revolutionary” is like “humorous” – overwhelmingly dependent on the cognitive rules of the person making the judgment. This is why an explained joke cannot be very funny and why, for example, I cannot judge a new, super-conducting epigenetometer as revolutionary.

    In the cases of both humor and revolution, at least one assumed rule of our cognitive framework must be violated in some way, typically in object categorization.

    Where we lack such rules, we cannot experience the humor, nor appreciate the surprise factor that triggers SME’s in a particular field to broadly agree that X is revolutionary.

  4. #4 dean
    United States
    December 30, 2015

    There’s little, if any, “real world” about evolutionary developmental biology.

    Thousands of scientists around the world, and hundreds of thousands of research articles, show that you are wrong.

    But, since you’ve never opened a science book, choosing to play the typical lying creationist, your latest blatantly false post is no surprise.

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