My Remedial Education: Haeckel’s Embryos
Science — By Joe Carter on February 4, 2004 at 1:35 am [Note: Read this post to learn more about this series.]
Think back to your high school or college biology textbooks and you’ll probably recall seeing a drawing commonly referred to as Haeckel’s embryos. The purpose of the illustration is to show the similarities among veterbrates during embryonic development*:
There’s just one problem with the drawing — it’s a fraud:
Generations of biology students may have been misled by a famous set of drawings of embryos published 123 years ago by the German biologist Ernst Haeckel. They show vertebrate embryos of different animals passing through identical stages of development. But the impression they give, that the embryos are exactly alike, is wrong, says Michael Richardson, an embryologist at St. George’s Hospital Medical School in London. He hopes once and for all to discredit Haeckel’s work, first found to be flawed more than a century ago.
…
The flaws in Haeckel’s work have resurfaced now in part because recent discoveries showing that many species share developmental genes have renewed interest in comparative developmental biology. And while some researchers–following Haeckel’s lead–like to emphasize the similarities among species, Richardson thinks studying the contrasts may be more interesting. Gilbert agrees: “There is more variation [in vertebrate embryos] than had been assumed.” For that reason, he adds, “the Richardson paper does a great service to developmental biology.” — Haeckel’s Embryos: Fraud Rediscovered, Elizabeth Pennisi : Science 277: 1435. 1997
Actual embryo development looks quite different than Haeckel’s drawings:
We shouldn’t feel too bad about being duped. Textbook writers fell for the forgeries even after this ‘discovery” was pointed out by Richardson. While one of the most widely used high school biology textbooks corrected the discrepancy in a 1998 edition, the college text were slower to adapt. Douglas Futuyma’s Evolutionary Biology, the premier introductory work in the field, failed to make the change in his text’s latest edition. Futuyma admitted that he wasn’t even aware that the drawings were fake, though he promised to remove the drawing in future editions.
Keep in mind that this is the type of “scientific fact” that is suppossed to be beyond question — until it’s exposed by one of their own. Forgive me if I have doubts, but this type of rigorous scholarship fails to inspire much confidence in the field of evolutionary biology. If such simple established “facts” can be proven false, what other inaccuracies might we find?
*Update: I’ve changed the original wording of this post in order to placate the evolution advocates. Now that I’ve removed their reason for claiming this is a strawman argument perhaps they will answer this question for me: If biologists knew that these illustrations were not accurate why were they used as the basis for subsequent textbook examples?
Tweet This
Digg This
Save to delicious
Stumble itAdditional comments powered by BackType
22 Comments
Yep. Anyone with even a passng interest to argue in this arena (pro or con) should follow this link to Amazon and read the reviews for Icons of Evolution by Wells and Sjogren. Embryo drawings, the peppered moth photos we all remember, and other “icons” get exposed. I’ve read the book and would recommend it.
-Brad
Infinite Monkeys
The peppered Moths were also a fraud:
http://www.touchstonemag.com/docs/issues/16.10docs/16-10pg10.html
I got lowered grades in school because I was a heretic on evolution. Now it seems that everything in the chapters on evolution are either irrelevant or hoaxes.
Also note that the embryo fraud is used to justify ABORTION because it basically says you are a salamander and N weeks of development.
They all look the same, if you don’t look closely and you have an agenda…
http://biocrs.biomed.brown.edu/Elephant%20stuff/Chapters/Ch%2013/Haeckel/Haeckel.htm
http://zygote.swarthmore.edu/evo5.html
http://www.gennet.org/facts/metro06.html
http://bevets.com/evolution.htm
They all look the same, if you don’t look closely and you have an agenda…
http://biocrs.biomed.brown.edu/Elephant%20stuff/Chapters/Ch%2013/Haeckel/Haeckel.htm
http://zygote.swarthmore.edu/evo5.html
http://www.gennet.org/facts/metro06.html
http://bevets.com/evolution.htm
Try this:
http://pharyngula.org/comments/9_0_1_0_C/
No, the biology is not fraudulent. Haeckel has been washed up for over a century, but the basic observation, that vertebrate embryos exhibit a remarkable similarity at one stage, is still valid. And actually, the observation was not first made by Haeckel, but by von Baer, an adamant creationist.
As for Wells…he’s an ignorant hack who doesn’t know what he is talking about, and consistently misrepresents the evidence. You might want to read Michael Richardson’s response to this sort of thing, since you’re citing him as support.
Whew, it’s a good thing that I only impregnated my girlfriend with a salamander. That’s a load off…
Michael Richardson’s statement on the misinterpretation and abuse of his studies by creationists:
“A recent study coauthored by several of us and discussed by Elizabeth Pennisi (Research News, 5 Sept. 1997, p. 1435) examined inaccuracies in embryo drawings published last century by Ernst Haeckel. Our work has been used in a nationally televised debate to attack evolutionary theory, and to suggest that evolution cannot explain embryology. We strongly disagree with this viewpoint. Data from embryology are fully consistent with Darwinian evolution. Haeckel’s famous drawings are a Creationist cause c
I don’t think these pictures have been used in bio-textbooks for awhile now (at least they weren’t in mine when I took bio 10 years ago).
I am amused by one thing: you lifted your copy of Haeckel’s drawing straight from my web site — same size, same filename, same scanning artifacts.
That’s perfectly OK, since the image is in the public domain, but you could have at least read the text I had wrapped around it before you made all the errors in your post.
PZ,
No, the biology is not fraudulent. Haeckel has been washed up for over a century,
Haeckel invented a bogus theory, the biogenetic law, to explain a valid observation. The theory was soundly rejected in the 19th century. The only people who bring it up to piss and moan about the credibility of scientific scholarship are creationists. His drawings lingered on because they were widespread in the popular press, and because they do have significant value in the history of science, which is how most textbooks used them. The chemistry textbooks also talk about phlogiston; it does not mean they endorse an erroneous idea.
As for similarities, do you have a notochord? A post-anal tail? How about pharyngeal arches? No, you don’t. But you did, once. And that’s the curious thing: we have these strange relics imbedded deep in our developmental history, and all other chordates have the very same things; and other organisms lack them. Why? Evolutionary biology explains why (they are remnants of a common ancestral bauplan) and makes predictions about what we’ll find as we look closer, such as that we’ll see similar molecules carrying out similar roles, and that those molecules will have similarities with those in other phyla.
As for your errors, you have misinterpreted a scientific paper as providing evidence against evolution, something the author (who, I presume you will agree, knows his work far better than you do) considers to be emphatically wrong. Of course, it may not be your error: you seem to be parroting the grossly erroneous work of Jonathan Wells.
Errors:
Think back to your high school or college biology textbooks and you’ll probably recall seeing a drawing commonly referred to as Haeckel
Per Richardson, “On a fundamental level, Haeckel was correct: All vertebrates develop a similar body plan (consisting of notochord, body segments, pharyngeal pouches, and so forth). This shared developmental program reflects shared evolutionary history.”
Per Chrysler, “On a fundamental level, Lee Iacocca was correct: All automobiles develop a similar body plan (consisting of a chassis, drive shaft, engine cavity, and so forth). This shared developmental program reflects shared evolutionary history.”
With all due respect, PZ, you might want to actually read my post before you criticize it. You seem to be the one in error:
As for your errors, you have misinterpreted a scientific paper as providing evidence against evolution
I did no such thing. I used the paper to show that a picture that was used in textbooks when I took biology courses has been discredited.
Of course, it may not be your error: you seem to be parroting the grossly erroneous work of Jonathan Wells.
Please show me where I have
You have explicitly claimed that “The purpose of the illustration is to show that as an organism passes through embryonic development it re-traces every stage of its evolutionary ancestry”. That is the biogenetic law. That claim is completely false; biology hasn’t taught the biogenetic law in the last century, except to state that it is false. I’ve reviewed a lot of textbooks in introductory biology, on the order of a score of authors in multiple editions, in some cases going back to the 60s. Haven’t found any that claim that yet, and I’ve found some awfully obscure books.
For contemporary texts, look up Campbell or Purves or Guttman or Raven. Or Levine and Miller, since you’ve already cited and linked to them.
And I’m afraid that what you’ve said here is simply warmed over Wells, nothing particularly original and nothing particularly accurate. Think about what you are saying here.
Creationist says biologists teach X, which is wrong.
Biologists say yes, X is very wrong — which is why we don’t teach it.
You pounce on X and say aha, we were right, you’ve been lying to us, how can we ever trust you?
Biologists say no — we didn’t lie to you anywhere. We threw out X in the 1890s. Creationist lied when he says we teach X. How can you trust him?
I found myself wondering what people have actually learned from the Haeckel drawing and its derivatives. What would a survey reveal for questions like these:
* Have you ever seen this picture before?
* Does it show that human embryos pass through various “animal stages” of devlopment (fish, amphibian, etc.)
* Is that evidence for the truth of evolution?
* Is it evidence against an intelligent designer?
I suspect that most would say “nope, never seen it before”…but most of the rest would answer “yes” to all questions. If my speculation proved correct, that would indicate a problem with biology education, right?
I must admit, I had never seen those photos. And it was indeed a fraud. But to use that fact to try to invalidate evolution as a whole is disingenuous at best.
Get the facts, man!
Joe:
If biologists knew that these illustrations were not accurate why were they used as the basis for subsequent textbook examples?
Because, unfortunately, textbook publishers are not themselves scientists, and woeful inaccuracies creep into textbooks of all stripes.
So my question is, and always has been, why does the similarity between embryos from differrent species have to mean that they have common evolutionary ancestry?
As far as I can tell the only difference between
This shared developmental program reflects shared evolutionary history. It also fits with overwhelming recent evidence that development in different animals is controlled by common genetic mechanisms.”
and
This shared developmental program reflects [a] shared [creator]. It also fits with overwhelming recent evidence that development in different animals is controlled by common genetic mechanisms.
is that you’ve already made up your mind about what the evidence will tell you.
Why is one considered valid science and the other not? Both take it on faith that their view is the right one.
The difference is that “completely different developmental programs” would also be compatible with a “shared creator”. The creator hypothesis is untestable and has absolutely no explanatory power; it fits any situation you can invent, including many that are ridiculously incompatible with how life actually works.
The theory of evolution is valid because it has been tested every step of the way for over 140 years, and has been the best and most powerful explanation available. You’re welcome to come up with a better explanation, and every biologist will gladly jump ship and adopt it. However, inventing super-powerful invisible beings who know everything and can do everything, but for which you have no physical evidence, is not such an explanation.
Actually, I think the point of a lot of people who have questions about evolution is that the theories can not be tested by science either. How do you recreate what evolutionists claim happened to get us to where we are today? The theory of evolution is only the “best and most powerful explaination available” if you’ve already decided that it is the only possible answer. I’ve been wondering why scientists haven’t come up with a better idea themselves for years now.
Go here: http://evolution.berkeley.edu/evosite/evohome.html
It’s a simple tutorial in evolutionary biology. In particular, read the “misconceptions” section — it covers the major errors creationists make, including the ones I see here.
A scientist who came up with a better idea than evolution would be the most thoroughly praised and appreciated biologist of all time. That would be the sure path to glory and fame in the field. I guarantee you that we’ve all been working our brains to the bone trying to find that better idea…and one of the signs that evolution is a really strong, solid idea is that we haven’t been able to beat it.