Return of the Son of the Bride of Haeckel


The Discovery Institute is so relieved — they finally found a textbook that includes a reworked version of Haeckel’s figure. Casey Luskin is very excited. I’m a little disappointed, though: apparently, nobody at the Discovery Institute reads Pharyngula. I posted a quick summary in September of 2003 that went through several textbooks, and showed a couple of examples where redrawn versions of Haeckel’s diagram were used. More recently, I posted a fairly exhaustive survey by Patrick Frank of the use of that diagram since 1923, which showed that it was rare, and that the concept of recapitulation was uniformly criticized. Really, guys, the horse of recapitulationism is dead. Biologists riddled it with bullets in the 19th century, and have periodically kicked it a few times to be sure. For Intelligent Design creationists to show up over a century later and flog the crumbling bones of a long extinguished horse and crow victory is awfully silly.

So how can you still find any vestiges of Haeckel’s work in textbooks?

That’s an interesting question, actually, and it has a complex answer. None of those answers involve the DI’s preferred explanation, that there is a worldwide conspiracy by biologists to prop up evolution with phony data, and Luskin’s specious “analysis” completely ignores a crucial point: that the textbook is using the diagram to support a valid scientific observation, and to criticize Haeckel’s interpretation.

So why does the infamous diagram still linger?

  • Conservatism. It’s amazing how much stuff lingers on for edition after edition in biology textbooks. They’re huge, they’re a lot of work, and new editions are in no way rewrites—the team of authors polish up and refine scattered bits, and maybe add a new chapter or two (it’s always “add”, it seems—they grow and grow, year after year.) For a classic example of this phenomenon, read Gould’s “The Case of the Creeping Fox Terrier,” which you can find in the collection “Bully for Brontosaurus”; somehow, most textbooks ended up describing early horse ancestors as being “the size of a fox terrier”.

  • Specialization. Biology is an immense discipline, and there is a dearth of generalists, of necessity. Darn few of the big textbook authors are developmental biologists, too…so the sections on development don’t usually get the same yearly reexamination that the other sections do. Also, if the Haeckel diagrams are there, they’re in the evolution chapter—and evo-devo experts are even rarer on textbook author bylines.

  • Historicity. Most textbooks that retain any mention of Haeckel do so because, like him or not, he was a very significant figure in 19th century biology. They keep him in as a symbol of our discipline’s history. The DI shouldn’t complain about that; they seem to be fascinated with him, churning out more stuff about Haeckel than all of the textbooks they complain so bitterly about.

  • Accuracy. Here’s something the DI never brings up: the image that is used in those textbooks? It’s not the one that Haeckel was accused of faking! It’s clearly been, to put it most charitably, drawn to serve Haeckel’s interpretations — extraembryonic membranes have been removed, for instance , and there are other signs that he emphasized what he thought was important and diminished what he thought wasn’t — but otherwise, it illustrates a real point: vertebrate embryos at the pharyngula stage resemble one another. There are better illustrations out there now, but remember that first point up there—textbook publishers and authors are conservative.

  • Science. This is one the DI always dodges. The books, even those few that still cling to the old diagram, do not argue for Haeckelian recapitulation. They argue against it. What you’ll usually see is a counterproposal, that the way to explain the similarities is by von Baerian recapitulation, which is a completely different matter. Von Baer argued that the cause of the resemblance is that early embryos express the most common, general morphological underpinnings of the phylum, and that development is a process of adding specializations to that general form. It is therefore to be expected that all members of a phylum will all have embryos with greater similiarity, because the unique features that distinguish the species haven’t been formed yet.

    The dead giveaway that the book is endorsing von Baerian recapitulation, not Haeckel’s version, is when they explain that embryos of one species resemble the embryos (not the adults) of other species.

Now look at Luskin’s victory cry. I am vastly amused that in an article that claims that the DI has been vindicated in its insistence that biology textbooks have been indoctrinating children in the Haeckelian lie, he has to use the phrases I have highlighted below.

The text not only discusses “ontogeny recapitulates phylogeny” but also affirms it, albeit in a slightly different form. This entire discussion comes from a subsection entitled “Ontogeny Recapitulates Phylogeny,” in which the authors repudiate Haeckel’s claim but then defend a reformulated version of it: “The developmental instructions for each new form seem to have been layered on top of the previous instructions, contributing additional steps in the developmental journey. This hypothesis, promoted in the nineteenth century by Ernst Haeckel, is referred to as the ‘biogenetic law.’ It is usually stated as an aphorism: ontogeny recapitulates phylogeny; that is, embryological development (ontogeny) involves the same progression of changes that have occurred during evolution (phylogeny). However, the biogenetic law is not literally true when stated in this way because embryonic stages are not reflections of adult ancestors. Instead, the embryonic stages of a particular vertebrate often reflect the embryonic stages of that vertebrate’s ancestors.” (pg. 1228-1229, emphases in original)

Note, too, that last sentence; they don’t mention von Baer, but those words are a clear indication that what they are discussing is von Baerian recapitulation. I would dearly love to see the DI go on a crusade against von Baer, just as they have for Haeckel; von Baer preceded Darwin, and was also probably the premier embryologist of the 19th century. Luskin and his fellows at the DI are so ignorant that they aren’t even aware of the significant differences in these two interpretations, and even think that von Baer’s explanation was a “reformulated version” of Haeckel’s, which would only have worked if von Baer had a time machine. His explanation preceded Haeckel’s by about 30 years.

So in short, the Discovery Institute has found a textbook illustration using Haeckel’s diagram several years after I told them where to look, and that textbook clearly and specifically argues against Haeckel’s biogenetic law, by their own admission. And this is a vindication of their claim?


I want to mention one other point that troubles me. I agree that textbooks should revise their sections on developmental biology extensively — it’s a field that is changing so quickly that there ought to be more effort put into representing it accurately (of course, every representative of every sub-discipline of biology is saying exactly the same thing about their field, but mine must be more important.) If any good was to come from the DI’s carping, it was that maybe the publishers would scrutinize the development sections of their books.

Unfortunately, some of what I’m seeing is the reverse. In my earlier post, I mentioned that the Campbell textbook had actually removed a superb illustration of embryonic homology between editions—and the removal was done for the edition that came out after Wells’ awful book that made bogus criticisms of many textbooks. I’d hoped it was just a coincidence.

But now, the odd thing: I actually praised Raven & Johnson’s Biology, 5th edition for including this nice, clean diagram.

i-a9570c8449528d6f4fc5581b5da441f0-raven20-18.jpg
Copyright © 1999 McGraw-Hill Companies, Inc.

That isn’t drawn from Haeckel, but from contemporary specimens. I like it—it highlights key similarities well.

If you look at the text the DI is now criticizing, though, it’s the 6th edition of Raven and Johnson, from 2002, after Wells’ book was published. I’m baffled. They had a good diagram, and they slid backwards to add an older, poorer one? I don’t have a copy of that edition, but I’m wondering now if they didn’t add it in response to the attention given to Haeckel’s work lately, with a clear explanation of why we don’t accept Haeckel’s explanation anymore.

It would be ironic if the reason they were able to find this illustration in a modern textbook is because the authors were listening to public concerns about it, and added it so they could specifically address the issue, especially since they are explicitly repudiating Haeckel. Apparently, the DI wants biologists everywhere to make a Stalinesque purge of every mention of Ernst Haeckel, even in those cases where we’re plainly disagreeing with some of his ideas, and teaching our students where they are wrong.

Comments

  1. Russell says

    Historicity is important. When students use only textbooks that are purged of ideas later proven wrong, they get the wrong idea about science. It would be a shame if the effect of the idiots at the DI is that more and more biology texts simply don’t discuss Haeckel, from fear that any mention of him will give them grist for their mill. It’s quite telling that they criticize even textbooks that get that discussion right.

  2. says

    History is certainly important… I don’t know much about biology, but in my physics class last semester there was a not insignificant portion of our lectures toward the end that covered how we gained our current understanding of the atom. Interesting on it’s own, but also helped explain how things work.

    I guess these guys just don’t like to see how a subject evolves…

  3. llewelly says

    Science is the story of how research and serendipity revealed evidence that showed old ideas to be incorrekt or incomplet, leading to new ideas and revisions of old ideas.
    Haeckel’s theories were show to be wrong by empiricism, and discarded. And that’s why the creationists are so fixated on him, why they work so hard to distort the history of how science tested and treated Haeckel’s ideas.

  4. says

    For a non-scientific person (ie. one that read ID materials) I actually doubt that they can tell non-Haeckelian drawing of embryos from other drawings of embryos. If they see embryo drawings that compare features they will automatically assume it has something to do with Haeckel.

  5. says

    Why is the DI fussing over recapitulationism when phlogiston is poised for a big comeback? Any minute now.

  6. CCP says

    For Intelligent Design creationists to show up over a century later and flog the crumbling bones of a long extinguished horse and crow victory is awfully silly.

    Alternatively punctuated (I wanted to put “spliced”) versions:

    1. For ID creationists to show up over a century later, flog the crumbling bones of a longextinguished horse, and crow victory is awfully silly.
    …which has too many commas for me too, but expresses what I believe you meant to express.

    2. For ID creationists to show up over a century later and flog the crumbling bones of a longextinguished horse and crow, victory is awfully silly.
    …in which case I feel bad for the crow, but agree that any ID victory would be pretty fucking silly. I admit that this one is not grammatically correct, but hey.

    3. For ID creationists to show up over a century later, flog the crumbling bones of a long, extinguished horse, and crow victory is awfully silly.
    …again with the commas, but: cool, how long was this horse? Does Darren Naish know about it?

    4. For ID creationists, to show up over a century later and flog the crumbling bones of a long extinguished horse and crow victory is awfully silly.
    …I guess this would have to be one of the vanishingly few times that I find myself in agreement with ID creationists; that is pretty siily.

    5. For Intelligent Design creationists to show up over a century later and flog the crumbling bones of a longextinguished horseandcrow victory is awfully silly.
    …actually, I suspect that had crows and horses banded together a century ago, they would still have had a small chance of victory (alas, no more), but that yeah, by now it would have been long extinguished.

    …and many highly diverting permutations of the above suggestions, left as an exercise for the reader.

  7. Mark Borok says

    I recall being taught that “ontogeny recapitulates phylogeny” in grade school in the late 70’s. Maybe I’m misremembering it and that phrase came from an out-of-date text on evolution, but I’m pretty sure I recall my 4th grade teacher saying it. Don’t know. Probably mistakes can creep into even the best teaching at the elementary school level. I also had a teacher who used “archeology” when she meant “paleontology”. Being an obnoxious nerd, I stood up and corrected her loudly the second time she did so.

  8. says

    Yes, you can also find people who were taught creationism in high school.

    And you can find even more examples in pop culture and fields unrelated to biology. Take a look at Dr Spock’s Baby Book sometime — there’s shameless Haeckelian recapitulation as a rationalization sprinkled throughout.

  9. J-Dog says

    New Motto for The DI:

    We’ve Evolved – From Creating a Trojan Horse to Beating a Dead Horse

  10. RavenT says

    I titled my master’s thesis on knowledge representation in comparative anatomy “Ontology Recapitulates Phylogeny” just because it amused me. Watch *that* pun come back to bite me in the ass with these low-level parsers someday!

  11. Peter McGrath says

    Such blatant use of outdated science has put my humours out of balance. I shall have to go and bleed myself.

  12. RamblinDude says

    This isn’t my area of expertise but the object lesson here is pretty general.

    I’ve never heard a credible–and usually impassioned–counter argument from a creationist that wasn’t ‘science derived’ in origin. (The key word here is credible, not the thoroughly stupid arguments like, ‘evolution contradicts the second law of thermodynamics’, or “I kicked some stones at the Grand Canyon and it seems like it could have been carved out in the Great Flood of Noah”.)

    Most of their “AHA…SEE!” moments are second hand insights pilfered from within the self correcting scientific method. And they never seem to recognize the irony.

    They point smugly to the ‘Piltdown Man’ hoax, without ever crediting scientists for uncovering the hoax.

    Every time they find some scientific contradiction–no matter how obscure or irrelevant, or resolved by science–they dance all over it like pirates on a gold chest, and tell their faithful flock, “See? You can’t trust science.”

    It always amazes me that people who talk about the need for morality in this country have no problem deceiving people and spreading misinformation.

    Meanwhile, science marches on and these dimwitted Monty Python rejects just get stupider–and more subservient.

    Okay, it’s out of my system now.

  13. richCares says

    with as many errors as Casey makes, he must be aware of his lack of brain power. This is actually quite typical of “born agains”, you see it is OK to lie for Jesus.

  14. BMesser says

    On a slightly different subject, I’ve often wondered why introductory text books are written by a single author. Especially in as diverse a field as Biology. It seems like it would make more sense to have the entire department join in, or at least several people in a given department, so that each chapter recieved the attention it deserved. Obviously there isn’t enough room to put *everything* into an intro text. Still, it seems to me that an expert in a particular branch of Biology would be the perfect person to know what key ideas are needed to give first year students an accurate view of that field. Is it just an issue of time and editing that prevents this from happening?

  15. ji says

    And yet like the Energizer bunny, they just keep going and going and going and going and going and going and going and going and going and going and going and going. When will the madness end?

  16. Richard Rodriguez says

    Back in the 80’s there was a movie titled “The Prophecy” about some mutated bear that was terrorizing the couuntryside somewhere in the northwest. The gist was that a local paper mill was polluting the nearby waters with mercury. At the start of the movie, if I remember right, they showed an image of what appared to be an embryo, and a voiceover actually says, among other things, that embryos retrace their evolutionary history going from fish to reptile to mammal during their development. I am sure many people took the voiceover’s comments as mainstream science.

  17. Ichthyic says

    Richard-

    Here’s your official invitation to the endless bad sci-fi marathon I have planned in my little circle of Hell, for having found one of the films I had planned on showing (a long time favorite, btw).

    …and the sequel (yes, there was a sequel).

    bring your own popcorn.

    see you there!

    ;)

  18. RavenT says

    A bad science fiction movie about mutated bears?!?!?!

    I am *so* there; expecially if we can make it a double feature with Savage Planet.

    See you in Hell, Ichthyic!

  19. Ichthyic says

    See you in Hell, Ichthyic!

    all are welcome…

    just stay AWAY from the light, and then after you go past the main gate, make a right at the giant squid pit.

    You can’t miss it.

    I hired Joel Hodgson as MC.

  20. says

    RamblinDude:

    Every time they find some scientific contradiction… they dance all over it like pirates on a gold chest….

    Arrr, don’t ye be insultin’ the pirates around these parts, y’hear? We be nothin’ like these cretins.

  21. GvlGeologist says

    Looking at this, I wonder if the IDC’ers will look at geology texts and claim that, because many of them still discuss (as wrong) both Archbishop Ussher’s 4004 BC age of the earth and William Thompson (Lord Kelvin)’s 20-400 million year age of the earth, we still believe them, and are lieing about the 4.55 billion year age.

  22. David Marjanović says

    It seems like it would make more sense to have the entire department join in, or at least several people in a given department, so that each chapter recieved the attention it deserved.

    Department?

    Are schoolbooks written by university professors in the USA (like they were 50 years ago in France)? In Austria they are written by school teachers, usually failed or failing ones.

  23. David Marjanović says

    It seems like it would make more sense to have the entire department join in, or at least several people in a given department, so that each chapter recieved the attention it deserved.

    Department?

    Are schoolbooks written by university professors in the USA (like they were 50 years ago in France)? In Austria they are written by school teachers, usually failed or failing ones.

  24. Owlmirror says

    I tried following the link to Raven and Thompsons’s book, which did not work for me (as an instructor, there may be pages that you can access that the public cannot). But I tried searching around on the McGraw-Hill site a bit, and stumbled upon this:

    http://www.mhhe.com/biosci/genbio/espv2/data/evolution/index.html

    And if you expand and follow links, you get this in the section on embryos:

    http://www.mhhe.com/biosci/genbio/espv2/data/evolution/001/mainframe17.html

    Which are, indeed, the embryos drawn by Haeckel.

    Sorry.

  25. GvlGeologist says

    10,000,000 years/4,560,000,000 years x 100% = 0.2%

    You’re wound a little tight, there, David!

    ;^}

  26. Owlmirror says

    Er, not Thompson. That should have read “Raven & Johnson“.

    McGraw-Hill only shows the 7th and (presumably upcoming) 8th editions, not the 5th or 6th, for that author search.

  27. says

    Why apologize? That’s what I’m saying: they’re there, but the section is on the history of the science, and rejects the Haeckelian interpretation…so it’s no big deal.

  28. says

    Ramblindude said: Every time they find some scientific contradiction–no matter how obscure or irrelevant, or resolved by science–they dance all over it like pirates on a gold chest, and tell their faithful flock, “See? You can’t trust science.”

    Indeed. The key to countering this attack is to note that it’s the rate and extent of error for science vs whatever the alternative epistemology is, that matters, not a comparison to some idealistic abstract standard of perfect knowledge that too many people presume is even feasible. I think this old article by Asimov really nails this point. Whatever mistakes science has made, faith, rationalism, revelation, authoritarianism, and all the other methods have made far worse mistakes for far longer. And when science makes a mistake, it’s usually science that corrects it.

    That the creationist/IDers focus so much on someone who died nearly a century ago shows how stagnant their view of knowledge is, and just how unscientific they really are. It’s akin to someone arguing that horses are superior to automobiles and only considering Model T’s in the comparison.

  29. snaxalotl says

    as supporters of the side of truth and goodness, we have no need to shy away from open discussion, unlike the creationists

    so I would suggest it might clarify things to state up front the way that Haeckel is correct to some degree. We know that the important point is that progressively earlier stages of development are similar to early stages of progressively older ancestors (hence progressively more distant relatives, which is generally the more useful perspective). But an additional point is that, as you go back far enough, any given developmental stage becomes progressively more like the final adult form. So in a second order sense, earlier stages of development become more like (which doesn’t mean very like – I’m only talking about a degree of correlation) ancestral adults. This similarity is not very important, because it doesn’t incorporate the reality that lineages generally involve adult stages of evolving form but equivalent complexity, but I think this correlation is what drove Haeckel’s intuition, especially as it is so easy to mischaracterize evolution as a steady increase of complexity. So we know Haeckel is wrong in his conclusion, but I think people have been unnecessarily embarrased into avoiding the statement that Haeckel is slightly right. This adds to the confusion, and confusion only benefits the (as always, anti-science) creationists.

  30. Ichthyic says

    I’m there on the bad sci fi convention. I’ll bring Green Slime and Fantastic Voyage.

    good choices.

    do you happen to have a copy of “the crawling eye”?

    haven’t managed to scrape that one out of the pit yet.

  31. stmarnock says

    Anyone else noticed the section at their gimpsite http://www.evolutionnews.org under “About This Site”? And I quote: “The misreporting of the evolution issue is one key reason for this site”.

    Freudian or what?

  32. Albatrossity says

    Any circle of hell that features bad sci-fi flicks needs to include

    Robot Monster (aka Ro-Man), where the creature is a robot clad in a bear suit (complete with visible zippers), topped by an old-time diving helmet.

    The Creeping Terror, where the creature is a gunny-sack into which the victims have to crawl; it apparently doesn’t move well by itself.

    Fiend Without a Face, where the creatures are invisible brains and spinal cords, which are eventually made to materialize after they consume enough victims.

    And, of course, Barbarella!

    I can bring them all; when’s the party start?

  33. says

    Speaking of faked diagrams – faked photos, actually – the talkdesign web site has a picture of a flagellum by scanning electron microscope. It looks more symmetrical and mechanical than any SEM image of a flagellum that I’ve ever seen. The figure caption explains: it’s a composite image and it has been “improved” by rotational averaging. In other words, while it looks like a scanning electron photomicrograph, it’s not.

    At least that page, by N. M. Matzke, acknowledges that the image has been doctored. Other pages, such as this Icky site (scroll down about 5/6 of the page, averting your eyes from the bombardier beetle wheeze, to find the picture). It simply says that this is how the flagellum looks under an electron microscope. And that this device is a Molecular ENGINE (caps in original).

    And then they have the brass balls to whinge that the Haeckel diagrams are mentioned as a superseded idea!

  34. mangal says

    So in short, the Discovery Institute has found a textbook illustration using Haeckel’s diagram several years after I told them where to look… These uys wouldn’t know to find their you know what with both hands!

  35. says

    You have to have “Godzilla vs. the Smog Monster” or your bad sci-fi-movie roast won’t be complete. Did you ever notice that the movie version of SF is really just horror?

  36. says

    Owlmirror, that online science “companion” does seem a bit sloppy: for instance, they list “wheat germ” as a species. Obviously I wasn’t editing it!

    I ran into a fellow editor on the subway once, pulling little scraps of paper out of his briefcase and making notes on a page. When I asked what he was doing, he said he was editing a grade-school maths texbook: those scraps were the manuscript he’d received from the author.

  37. Dave Wisker says

    do you happen to have a copy of “the crawling eye”?

    haven’t managed to scrape that one out of the pit yet.

    I have a copy. Also, no bad scifi fest would be complete without giant mutated bloodthirsty rabbits, so Night of the Lepus should be mandatory.

  38. says

    Two thoughts. I don’t think you should say recapitulation is uniformily criticized. As you say later, the Haekel version is, but the Van Baer version is not.

    Secondly, I think it always important to remember that we like the Van Baer interpretation, but Van Baer was a Literal Creationist, who, in a time when evolutionary hypothesis (pre-Darwin) weren’t branching but rather linear, argued for the similarities between embryos as proof that evolution was *false*. Evolutionists, however, will use good data, regardless of it’s source, even if the arguement previously was used in favor of Literal Creationism. The Literal Creationists and IDers of today are actually criticizing the arguments of one of their own, when they deny any similarity in embryos, or the meaning of this.