Modern books that still use Haeckel’s embryo drawings

[Aggie]

This is an offshoot of something that was discussed in this thread, but I’d like to examine one particular aspect of the topic that was discussed there.

In that thread, Marktheblake made the assertion that Enrst Haeckel’s drawings of embryos are still commonly cited as accurately portraying similarities between them, even though it’s well-known at this point that Haeckel exaggerated the similarities in these drawings. Thistlethorn responded that he doubted this was the case:

What prominent museum displays Haeckel's drawings as the truth of how embryos develop? If any museum does that, you could claim that the museum in question is doing the teaching of evolution a disservice. Haeckel's drawings have been oft criticized by evolutionary biologists - such as Steven Gould - for being exaggerated, and are only present in modern textbooks for their historical significance. Embryology is nowadays taught using photographs, not Haeckel's drawings.

I’ve been curious to know whether Thistlethorn was right about this. In that thread, I mentioned one book I could think of offhand that contains Haeckel’s drawings, without mentioning that they’re exaggerated: Donald Prothero’s 2007 book Evolution: What the Fossils Say and Why it Matters, which has them on page 110. Today, I was looking to see whether any of my other books about evolution do the same thing.

So far, I’ve found the same thing in two other books: Douglas Futuyma’s textbook Evolutionary Biology: third edition, which was published in 1998 and has them on page 653, and Ernst Mayr’s book What Evolution is, which was published in 2001 and has them on page 28. Both of these books use Haeckel’s drawings specifically as a depiction of how the embryos of all vertebrates are similar to one another, without mentioning that the drawings exaggerate these similarities. Mayr’s book states that this diagram is taken from Monroe Strickberger’s 1990 textbook Evolution, so that’s at least one other book that uses these images the same way. (I assume that Strickberger’s book doesn’t mention the similarities are exaggerated in these drawings, since Strickberger’s book is being cited by Mayr, and I doubt Mayr would use these drawings in a way that contradicts his source material.)

Split Rock mentioned here that the reason Prothero uses Haeckel’s drawings without mentioning they’re exaggerated might be because as a paleontologist, Prothero isn’t familiar with embryology. But I don’t think Mayr and Futuyma have that excuse. They are (or were, in Mayr’s case) two of the most highly-regarded evolutionary biologists in the world, and Futuyma’s book in particular is the single most oft-cited source about evolution that I’ve ever encountered. I find it kind of surprising that both of them made this mistake.

I would be interested to know if anyone can find any other evolution-related books (or museums, in the case of what Marktheblake was talking about) that continue to use these drawings as a demonstration of similarities between embryos, without mentioning their inaccuracy. The selection of books in which I’ve found this is just based on what books I happen to own (or my girlfriend owns, in the case of the Futuyma book.) Considering that the books which make this mistake include two of them by such highly-regarded authors, including one that’s used a source for a huge number of other books, I suspect that it’s pretty common.

As far as I’m concerned, the claim that these drawings accurately represent similarities between embryos is an evolutionary PRATT. In terms of both how widespread it is and how long ago it was debunked, it’s about as bad as anything we’ve seen from creationists. Does anyone have a theory about why authors as highly-regarded as Ernst Mayr and Douglas Futuyma are still propagating this claim, over 100 years after it was shown to be false?

 

[Alunyel]

As I understand it, the only thing that was actually wrong with Haeckel's drawing, was that they were a gross exaggeration of the similarities.

I guess you could use them simply to illustrate the point, so long as you also point out the exaggerations, but I don't really see why anyone would bother, especially now we can easily take photos of embryological development, which is obviously a lot more accurate.

 

[Aggie]

As I understand it, the only thing that was actually wrong with Haeckel's drawing, was that they were a gross exaggeration of the similarities.

According to Ludwig Rutimeyer, who originally pointed out the exaggeration, Haeckel’s “illustrations” of embryos from some of the animals on that chart are actually made from the exact same woodcut print that he used for the embryos of other animals. In other words, some of them are made from a woodcut that wasn’t even intended to represent the animals that they’re labeled as. Even if that’s “the only thing” wrong with these drawings, it’s a pretty big one.

I guess you could use them simply to illustrate the point, so long as you also point out the exaggerations, but I don't really see why anyone would bother, especially now we can easily take photos of embryological development, which is obviously a lot more accurate.

But these authors don’t point out the exaggerations. They just say that these drawings show how the embryos of all animals are similar to one another, which is false—the embryos of all animals are similar to one another, but not in the way shown by these drawings. I’m looking for an explanation for why well-respected evolutionary biologists are propagating a claim that’s so obviously inaccurate.

 

[AV1611VET]

As I understand it, the only thing that was actually wrong with Haeckel's drawing, was that they were a gross exaggeration of the similarities.

Is that techno-speak for "Haeckel lied"?

 

[plindboe]

Aggie, you might be interested to know that I have Futuyma's "Evolution" (2005) and he doesn't use Haeckel's drawings there, but use photographs instead. So that's an improvement at least.

My guess is that old inaccurate drawings are mainly used out of tradition and nostalgia (though I'm also sure ignorance plays a part). Modern scientists tend to forgive the scientists of the past, who often let their bias creep into their work, because scientists today recognize that we live in a very different time. Today, biased and shoddy science ruins scientists' reputation, and deliberate distortion is considered the ultimate unforgivable crime. 100-150 years ago there wasn't the same awareness and focus on bias.

Mendel's work has also been shown to be practically statistically impossible. But his research is presented in just about any introductory book on genetics out there. If creationists were rejecting genetics, I'm sure they'd make just as much noise about Mendel and his experiments as they do about Haeckel's drawings.

Peter

Edited to add: In Futuyma's case it appears to have been ignorance. Several Google results say that he admitted his error in 2000 after consulting a developmental biologist.

 

[Alunyel]

Is that techno-speak for "Haeckel lied"?

Yes, to an extent.

It's like drawing a caricature of someone, and saying it's an accurate drawing of them.

It's obviously not an accurate drawing, their main features are exaggerated, but it's still a picture of them.

 

[Aggie]

Modern scientists tend to forgive the scientists of the past, who often let their bias creep into their work, because scientists today recognize that we live in a very different time. Today, biased and shoddy science ruins scientists' reputation, and deliberate distortion is considered the ultimate unforgivable crime. 100-150 years ago there wasn't the same awareness and focus on bias.

Apparently it could ruin scientists’ reputation in Haeckel’s time also. In the “false proofs” thread, I quoted a book from 1915 about what eventually happened to Haeckel because of this:

The Zoologists of Germany were, therefore, compelled, much against their will, to throw Haeckel overboard in order to save their own honor.

"A statement signed by 46 professors representing 25 German and Austrian universities and scientific schools discredited Haeckel's work (No. 8, Munchner Allgemeine Zertung) and 36 other scientists representing nineteen universities, botanical laboratories, etc., of Germany, Switzerland and Austria, including the University of Jena agreed in demanding 'that henceforth as in the past, German scientific research shall rest on an uncompromising love of truth.' 'Yet the past holds an ugly record.' In 1868, Haeckel printed off one and the same diagram three times in succession to show the marvelous similarity of the embryos of man, ape and dog. Rutimeyer called attention to this curious device, whereupon Haeckel conceded that he had been guilty of a thoughtless piece of folly. 'The end of his career is therefore worthy of the beginning (Augsburger Post-Zeitung, March 23, 1909)' Repudiation of Haeckel is now unanimous and complete; he is discredited by the signed verdict of eighty-two of the foremost German authorities."

I would like to know what other recent evolution books there are that still use these drawings, but I think I’ve reached the limit of what’s possible with the evolution books that I own. If anyone else has access to some well-known modern books about evolution that I haven’t mentioned, I’d be interested to know what the answer is for them.

In any case, it seems to be a common assertion among supporters of evolution that no modern books about evolution present these drawings as something that’s accurate, but I think I’ve shown that claiming this is the same kind of wishful thinking that Haeckel demonstrated with the drawings themselves. As beneficial as it is that Futuyma realized nine years ago that they were inaccurate, that’s still over 100 years after Rutimeyer first demonstrated this fact; a biologist of Futuyma’s stature never should have made this mistake to begin with. Hopefully after this thread, people here won’t continue to claim that modern books don’t use these drawings.

 

[Split Rock]

Is that techno-speak for "Haeckel lied"?

You're the King of Sophistry here. Maybe you could come up with a better phrase that makes Haeckel seem even less culpable... like you do with "Creation Scientists."

 

[Split Rock]

Split Rock mentioned here that the reason Prothero uses Haeckel’s drawings without mentioning they’re exaggerated might be because as a paleontologist, Prothero isn’t familiar with embryology. But I don’t think Mayr and Futuyma have that excuse. They are (or were, in Mayr’s case) two of the most highly-regarded evolutionary biologists in the world, and Futuyma’s book in particular is the single most oft-cited source about evolution that I’ve ever encountered. I find it kind of surprising that both of them made this mistake.

I have Futuyma's first edition, and I cannot find it there... interesting that he added it in later editions. I actually took a course on Evolution with him at Stony Brook. Although Futuyma is not a developmental biologist or embryogist either, it was sloppy to include it.

As far as I’m concerned, the claim that these drawings accurately represent similarities between embryos is an evolutionary PRATT. In terms of both how widespread it is and how long ago it was debunked, it’s about as bad as anything we’ve seen from creationists. Does anyone have a theory about why authors as highly-regarded as Ernst Mayr and Douglas Futuyma are still propagating this claim, over 100 years after it was shown to be false?

I would say that the use of Haeckel's drawings is a PRATT, but not the argument it is used to support.

 

[Naraoia]

I’ve been curious to know whether Thistlethorn was right about this. In that thread, I mentioned one book I could think of offhand that contains Haeckel’s drawings, without mentioning that they’re exaggerated: Donald Prothero’s 2007 book Evolution: What the Fossils Say and Why it Matters, which has them on page 110. Today, I was looking to see whether any of my other books about evolution do the same thing.

Prothero's book has a lot of details that make me want to throw things

I would be interested to know if anyone can find any other evolution-related books (or museums, in the case of what Marktheblake was talking about) that continue to use these drawings as a demonstration of similarities between embryos, without mentioning their inaccuracy. The selection of books in which I’ve found this is just based on what books I happen to own (or my girlfriend owns, in the case of the Futuyma book.) Considering that the books which make this mistake include two of them by such highly-regarded authors, including one that’s used a source for a huge number of other books, I suspect that it’s pretty common.

I could count the number of times I opened my evolution textbook (Ridley's Evolution, 3rd edition - I could check it for you once I'm back in Scotland) on my two hands, but I've seen the infamous drawings on more than one lecture slide.

As far as I’m concerned, the claim that these drawings accurately represent similarities between embryos is an evolutionary PRATT. In terms of both how widespread it is and how long ago it was debunked, it’s about as bad as anything we’ve seen from creationists.

I think we can agree on that. Thankfully, we have the good examples, too.

Does anyone have a theory about why authors as highly-regarded as Ernst Mayr and Douglas Futuyma are still propagating this claim, over 100 years after it was shown to be false?

My bet is on ignorance. Based on the publication info on wikipedia, Futuyma's research doesn't have a lot to do with vertebrate development.

Something that I can also see as contributing is availability. I'm pretty sure Haeckel's drawings (or derivatives) are very easy to obtain - is the same true of more accurate comparative pictures?

 

[Split Rock]

Prothero's book has a lot of details that make me want to throw things

I have that book... any other examples you would like to share with us?

 

[plindboe]

Apparently it could ruin scientists’ reputation in Haeckel’s time also. In the “false proofs” thread, I quoted a book from 1915 about what eventually happened to Haeckel because of this:

Point taken.

I would like to know what other recent evolution books there are that still use these drawings, but I think I’ve reached the limit of what’s possible with the evolution books that I own. If anyone else has access to some well-known modern books about evolution that I haven’t mentioned, I’d be interested to know what the answer is for them.

The books I have are the aforementioned "Evolution" by Futuyma and "Evolution" by Barton, Briggs, Eisen, Goldstein and Patel, and neither appear to have the drawings.

In any case, it seems to be a common assertion among supporters of evolution that no modern books about evolution present these drawings as something that’s accurate, but I think I’ve shown that claiming this is the same kind of wishful thinking that Haeckel demonstrated with the drawings themselves. As beneficial as it is that Futuyma realized nine years ago that they were inaccurate, that’s still over 100 years after Rutimeyer first demonstrated this fact; a biologist of Futuyma’s stature never should have made this mistake to begin with. Hopefully after this thread, people here won’t continue to claim that modern books don’t use these drawings.

Agreed.

It's not a claim I've ever made myself, but it does indeed pop up from time to time.

Peter

 

[Aggie]

Prothero's book has a lot of details that make me want to throw things

What else is there like this? I was thinking of recommending Prothero’s book in my own book that I’m working on, but if it has a lot of other inaccuracies also, maybe I shouldn’t.

Something that I can also see as contributing is availability. I'm pretty sure Haeckel's drawings (or derivatives) are very easy to obtain - is the same true of more accurate comparative pictures?

Probably not, but that’s mostly just a result of how bad this problem is. Haeckel’s drawings (and especially Romanes’ reproductions of them) have appeared in a huge number of biology books—probably more than any other comparison between embryos, including more accurate ones. And the more biologists continue to reproduce these drawings because they’re well-known, the worse this problem gets.

What Evolution Is is the only book by Ernst Mayr that I own, but I suspect that it’s not the only one of his books to contain these drawings. Mayr was the author of around 25 well-regarded biology books, and What Evolution Is was the second-to-last of them, having been published when Mayr was 97. Unless he discovered the inaccuracy of Haeckel’s drawings between then and the time when his final book was published, it seems like he probably didn’t realize this about them at any point during his life.

 

[Baggins]

Ernst Mayr's book has embryo drawings but they aren't Haeckel's; according to my copy they are drawings of embryos from Strickberger and Monroe's 1990 book Evolution.

If you see pictures of embryos in a modern evolution text why would you assume they were Haeckel's? People didn't stop making drawings of embryos because Haeckle exaggerated his.

I would assume that the other books similarly use drawings of embryos that aren't Haeckels, I find it bizarre that you think all these embryo drawings in modern texts are after Haeckel when he has been known to have been a fraud for over a century

 

[Thistlethorn]

I must say I never thought this was as big a problem as it obviously is. I've never encountered a book reproducing the drawings without describing them for what they actually are: decent approximations, but not scientific, but it seems there are quite a few text-books out there that perpetuate the fallacious drawings.

Thankfully, every time someone takes a look at this and contacts the authors in question pointing the inaccuracies out, we can collectively improve the scientific literature. I hope you're actually taking this step next.

Edit: Reading Baggins' post above, it occurs to me that his scenario is more likely to be true than Haeckel's drawings having been reproduced. Are you, OP, certain that the drawings you have seen are Haeckel's drawings?

 

[Aggie]

By the way, the article by Kenneth Miller that Naraoia linked to gives a fairly good explanation about this problem:

This idea has been pushed back into the news recently by the news that Haeckel's drawings of embryonic similarities were not correct. British embryologist Michael Richardson and his colleages published an important paper in the August 1997 issue of Anatomy & Embryology showing that Haeckel had fudged his drawings to make the early stages of embryos appear more alike than they actually are! As it turns out, Haeckel's contemporaries had spotted the fraud during his lifetime, and got him to admit it. However, his drawings nonetheless became the source material for diagrams of comparative embryology in nearly every biology textbook, including ours!

The emphasis is mine. Apparently, before the publication of Richardson’s 1997 paper about this, most biology books made this mistake, and it’s only within the past 12 years that this has begun to change.

This looks like it’s an example of something that creationists were getting right before supporters of evolution were. I’ve seen creationist material dating back to the 1970s that points out the inaccuracies of Haeckel’s drawings, including tracts by Jack Chick.

Ernst Mayr's book has embryo drawings but they aren't Haeckel's; according to my copy they are drawings of embryos from Strickberger and Monroe's 1990 book Evolution.

If you see pictures of embryos in a modern evolution text why would you assume they were Haeckel's? People didn't stop making drawings of embryos because Haeckle exaggerated his.

I would assume that the other books similarly use drawings of embryos that aren't Haeckels, I find it bizarre that you think all these embryo drawings in modern texts are after Haeckel when he has been known to have been a fraud for over a century

I know Strickberger’s book is what they’re sourced from, but look at the drawings themselves, and compare them to this image at Wikipedia of Haeckel’s embryo drawings. Even though Haeckel isn’t mentioned as the source, it’s the same image.

 

[Aggie]

Edit: Reading Baggins' post above, it occurs to me that his scenario is more likely to be true than Haeckel's drawings having been reproduced. Are you, OP, certain that the drawings you have seen are Haeckel's drawings?

In order to show that these authors are reproducing the same image that’s been shown to be inaccurate, I’m going to post a comparison between them. This is a scan of the embryo comparison in Futuyma 1998:

This is a scan of the diagram in Mayr 2001:

And this is a scan of the diagram in Prothero 2007:

And here’s the original drawing, at Wikipedia. If you go to File:Haeckel drawings.jpg - Wikipedia, the free encyclopedia, that page has some information about this image to verify where it’s from.

They’re all the same image, aren’t they? If they’re not, they’re copies of it that are so exact as to preserve all of the same inaccuracies that are present in the original.

 

[Thistlethorn]

Certainly appears to be the same images. You should contact the individual authors or their publishers and notify them of this error.

 

[Aggie]

Ernst Mayr died in 2005, and according to Plindboe in post #5, Douglas Futuyma found out about this mistake in 2000. I could try contacting Donald Prothero, though. Does anyone know how to contact him?

 

[Naraoia]

I have that book... any other examples you would like to share with us?

The one that literally made me scream was that he confused prokaryotic and eukaryotic flagella (p156, I believe). Let's see a few others (I have like thirty pages of notes, and I'm nowhere near finished with the booka ):

- An entire chapter about the origin of life that doesn't tackle the origin of nucleotides and doesn't even mention the RNA world hypothesis.

- The overconfidence with which he says that the phylogeny of major animal groups is no longer disputed (p136). Admittedly I've only just touched the surface of animal phylogenetics in my reading, but my impression is that the state of the field... um, doesn't warrant such confidence. Not at the phylum level, anyway. And the moment you say things like that to creationists, you can bet someone's going to find out that the solid consensus you're implying doesn't exist.

- Things like this:

"As the DNA is transcribed by tRNA, it interprets each three-letter sequence as the code for one of the twenty amino acids (plus a few codes are used to stop the transcription of DNA)" (p96)

(Well... just... *cringe*.)

- Another bit about DNA that looks thoroughly confused (p98):

More importantly, the fact that 80-97 percent of DNA in most organisms codes for nothing at all (so far as we know) says that evolution and selection must work entirely on that remaining few percent of the DNA that does code for something. Those remaining few genes are known as regulatory genes. They are the master switches that control the reading of the rest of the DNA, some of which is used to make the basic structures of life (structural genes) and therefore does not differ between organisms.

(Who can spot the most mistakes?)

IOW, he seems to muddle molecular biology a lot.

- There's also a thing about the annelid --> mollusc "transition" (pp192-193). Basically, he's saying that annelid-like ancestors to "aplacophores" to monoplacophorans to other molluscs is a neat transitional series. Now, that idea bleeds... For example, "aplacophores" are not that segmented (IIRC, the only segmented thing about them is the nervous system, which shows some seriation in most bilaterians.), and they are certainly not more segmented than Neopilina. I guess we could say that if I had to pick a few convincing transitions for a book, this one wouldn't be among them.

Then there are countless minor issues like calling chitin a protein (p193), most of what he writes about Archaea (calling it Archaebacteria and a kingdom of bacteria, saying that they are the most primitive living things or that they mostly live in extreme environments), calling "worms" a phylum (p123), Pitx1 a Hox gene (p116), pterosaurs pterodactyls (*cringe*)...

Now I look like I'm bashing the book. To be fair, I don't actually think it's a bad book, but there are clearly areas Prothero is not comfortable with, and there are things that, IMO, are... cosmetically modified to make a point stronger.

(I have a distinct feeling that I'm too anal for my own good )