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Author Topic:   Haeckel in Biology Textbooks
Beretta
Member (Idle past 5597 days)
Posts: 422
From: South Africa
Joined: 10-29-2007


Message 31 of 72 (483125)
09-20-2008 5:01 AM
Reply to: Message 29 by Vacate
09-20-2008 4:41 AM


2007 Haeckel's Fraud continues....
Vacate writes:
Beretta writes:
I have found the Haeckel's embryo fraudulent scenario in a 2007 textbook -how more recent would you like it?
What textbook? I would be interested to look this up.
"Focus on Life Sciences" Maskew Miller Longman. First published in 2007. Chapter 7 (on evolution) p 121

This message is a reply to:
 Message 29 by Vacate, posted 09-20-2008 4:41 AM Vacate has replied

Replies to this message:
 Message 34 by Vacate, posted 09-20-2008 6:01 AM Beretta has not replied
 Message 43 by Modulous, posted 09-22-2008 1:54 PM Beretta has replied

  
Dr Jack
Member
Posts: 3514
From: Immigrant in the land of Deutsch
Joined: 07-14-2003
Member Rating: 8.7


Message 32 of 72 (483127)
09-20-2008 5:53 AM
Reply to: Message 25 by Taz
09-20-2008 2:21 AM


Re: Haeckel's Embryos
I'm curious. Do you actually deny that embryos of different species at earliest stages look like each other? Because for one thing they actually are pretty darn similar to each other at the earliest stages. So, are you lying for jesus or just playing dumb?
We should be cautious about overstating the similarity of early embryonic stages; while there are significant similarities in embryonic development both at the macroscopic and biochemical levels; the phylotypic stage as presented by Haeckel (and others) is a simplification.
ref: Richardson, M.K., Hanken, J., Gooneratne, M.L., Pieau, C., Raynaud. A., Selwood, L. and Wright, G.M. (1997): There is no highly conserved embryonic stage in the vertebrates: implications for current theories of evolution and development. Anatomy and Embryology 196(2): 91-106

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 Message 25 by Taz, posted 09-20-2008 2:21 AM Taz has replied

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Dr Jack
Member
Posts: 3514
From: Immigrant in the land of Deutsch
Joined: 07-14-2003
Member Rating: 8.7


Message 33 of 72 (483128)
09-20-2008 5:57 AM
Reply to: Message 26 by Beretta
09-20-2008 4:07 AM


Re: Haeckel's Embryos -fake or not?
No, once again, that is not what he was doing. He was fraudulently representing the earliest stages of embryonic development as the most similar and again, this is not true. The midstages are the most similar -so he lied, selected only those cases that supported his case and represented the midstages as the early stages.
Can you identify a single labelled feature in Haeckel's drawings that is not present in the real embryos?
You throw around terms like 'lie' and 'fraud' with casual abandon, yet the central point that there is not a single feature in Haeckel's drawings not present in real embryos remains.

This message is a reply to:
 Message 26 by Beretta, posted 09-20-2008 4:07 AM Beretta has replied

Replies to this message:
 Message 56 by Beretta, posted 09-24-2008 6:56 AM Dr Jack has replied

  
Vacate
Member (Idle past 4600 days)
Posts: 565
Joined: 10-01-2006


Message 34 of 72 (483129)
09-20-2008 6:01 AM
Reply to: Message 31 by Beretta
09-20-2008 5:01 AM


Re: 2007 Haeckel's Fraud continues....
quote:
vacate writes:
What textbook? I would be interested to look this up.
"Focus on Life Sciences" Maskew Miller Longman. First published in 2007. Chapter 7 (on evolution) p 121
Well, I have the interest but I was thinking university level as I have access to most all the texts. I will give it a shot at the local grade school and hope they have the same edition. Thanks.

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 Message 31 by Beretta, posted 09-20-2008 5:01 AM Beretta has not replied

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 35 of 72 (483139)
09-20-2008 9:07 AM
Reply to: Message 28 by Beretta
09-20-2008 4:24 AM


Re: Haeckel and Darwin
Beretta writes:
A quote from your article on developmental biology that says they are most similar during the phylotypic stage rather than during the earlier or later stages of development. So obviously by the reckoning of your own article, the phylotypic stage is not the earliest stage and that is my repeated point.
This thread is about Haeckel's embryo drawings, and Haeckel was not focused on the "earliest stage" of embryonic development. Haeckel's drawings are not of the "earliest stage". They're all of embryos that have developed beyond the phylotypic stage.
The "phylo" portion of "phylotypic" derives from the word phylum. "Phylotypic stage" is a stage of embryonic development where it is common for embryos of animals of the same phylum to most resemble each other. Here is a set of Haeckel drawings illustrating multi-species embryo development:
Every organism in the top row, from fish to salamander and on across to human, already has a spinal chord (because they're all in the chordates phylum), so they are all obviously beyond the phylotypic stage.
In other words, Haeckel is silent on what you're calling the "earliest stage" of embryonic development, so it's not possible that he could be lying or fraudulent about it. If you're truly focused on this "earliest stage" prior to the phylotypic stage then you cannot be talking about Haeckel's embryo drawings. If you want to discuss earlier stages of embryonic development then you really should be posting to a different thread, or proposing a new one.
--Percy

This message is a reply to:
 Message 28 by Beretta, posted 09-20-2008 4:24 AM Beretta has replied

Replies to this message:
 Message 38 by Beretta, posted 09-20-2008 10:12 AM Percy has replied

  
Taz
Member (Idle past 3291 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 36 of 72 (483148)
09-20-2008 9:58 AM
Reply to: Message 32 by Dr Jack
09-20-2008 5:53 AM


Re: Haeckel's Embryos
Mr Jack writes:
We should be cautious about overstating the similarity of early embryonic stages
Of course we do. It all depends on the context of its mention in beretta's text book. He/she/it made it out to sound like the book said "everything looks like each other at the earliest stages of embryonic development therefore evolution is proven haw haw haw."
Notice how beretta hasn't stated anything specific about the supposed mention in the book or the text book itself. For now, we are still left with a bare mention.

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 Message 32 by Dr Jack, posted 09-20-2008 5:53 AM Dr Jack has not replied

  
Taz
Member (Idle past 3291 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 37 of 72 (483150)
09-20-2008 10:04 AM
Reply to: Message 27 by Beretta
09-20-2008 4:15 AM


Re: Haeckel's Embryos
beretta writes:
They are not most similar in the earliest stages as Haeckel clearly said they were -they are clearly distinguishable and only become more similar in the midstages.
I see that percy has already answered this.
So, again, are you lying for jesus or just playing dumb? Answer the the question.
Are you playing dumb or are you deceived OR are you lying for the cause of evolution and it's propogation as truth?
And exactly what statement by me are you referring to or do you just want to sound poetic?

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 Message 27 by Beretta, posted 09-20-2008 4:15 AM Beretta has not replied

  
Beretta
Member (Idle past 5597 days)
Posts: 422
From: South Africa
Joined: 10-29-2007


Message 38 of 72 (483151)
09-20-2008 10:12 AM
Reply to: Message 35 by Percy
09-20-2008 9:07 AM


Re: Haeckel and Darwin
They're all of embryos that have developed beyond the phylotypic stage.
The problem is that Haeckel presented the earliest stage (in his drawings) as the most similar but they are not most similar in the early stages -they actually start out looking very different, then converge somewhat in appearance midway through development before becoming more different again as adults.So the entire point of the 'ontogenic recapitulation of phylogeny' is lost if the embryos start out looking very different instead of looking very similar.
He represented the phylotypic stage as the early stage that looks most similar but obviously in order to press his point, left out the earlier stages where they look very different.
Haeckel is silent on what you're calling the "earliest stage" of embryonic development, so it's not possible that he could be lying or fraudulent about it.
It is fraud if he misrepresents midstages as early stages and fails to mention that they start out very different - which means the common ancestor imagination thing goes right out the window. They have to start out most similar and work through the supposed ancestral stages if what he was trying to say was actually true -which it isn't.

This message is a reply to:
 Message 35 by Percy, posted 09-20-2008 9:07 AM Percy has replied

Replies to this message:
 Message 39 by Percy, posted 09-20-2008 1:37 PM Beretta has replied

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 39 of 72 (483170)
09-20-2008 1:37 PM
Reply to: Message 38 by Beretta
09-20-2008 10:12 AM


Re: Haeckel and Darwin
Beretta writes:
He represented the phylotypic stage as the early stage that looks most similar but obviously in order to press his point, left out the earlier stages where they look very different.
Animal embryos begin as a single cell and then become two cells, four cells, eight cells and so forth, and over the next few days become a blastocyst of maybe a hundred or so cells. Inter-species differences during this stage cannot be great. In humans this stage is reached around day 5, and the phylotypic stage is reached around day 20, which is from 2% of gestation up until 8% of gestation. So your claim is that inter-species embryonic differences are significant between 2% and 8% of the gestational period. This seems unlikely given the short time period, the presence of few structures, and the small number of cells involved, but your welcome to try to support your position.
It is fraud if he misrepresents midstages as early stages...
Where did Haeckel ever claim that his drawings in the top row represented the earliest stage of embryonic development?
...and fails to mention that they start out very different...
This is something that you've failed to demonstrate yet. The textbook Principles of Developmental Biology says (and you quoted this yourself), "They are more similar to each other during the phylotypic stage than during earlier or later times of development." That the phylotypic stage is the point at which they are most similar does not support your claim that they are "very different" prior to that point.
The fact of the matter is that they are very, very similar, and I suspect that many would beg to differ with the textbook's description that the phylotypic stage is the point where they are most similar. Remember, that page is a summary of the chapter 's contents and was necessarily glossing over details. Since "phylotypic" is based on "phylum", the point it was most likely trying to communicate is that the phylotypic stage is the stage where embryos are most similar with respect to signature phylum characteristics, like spinal chords for chordates like ourselves. Anyway, embryos not much beyond the "clump of cells" stage don't have many significant ways in which they can differ. If you think they're significantly different prior to the phylotypic stage you'll have to demonstrate this.
They have to start out most similar and work through the supposed ancestral stages if what he was trying to say was actually true -which it isn't.
It is true that Haeckel's theory that embryological development represented a rather precise recapitulation of evolutionarily earlier adult forms was incorrect. We all agree on that, and this never became an accepted view within science anyway.
What is true is that embrylogical development across different species has many shared characteristics that are reflective of a shared evolutionary history, and any photographs or diagrams of equivalent embryonic stages across different species very effectively make this point.
--Percy

This message is a reply to:
 Message 38 by Beretta, posted 09-20-2008 10:12 AM Beretta has replied

Replies to this message:
 Message 40 by Beretta, posted 09-21-2008 9:27 AM Percy has replied
 Message 42 by Beretta, posted 09-22-2008 11:25 AM Percy has replied

  
Beretta
Member (Idle past 5597 days)
Posts: 422
From: South Africa
Joined: 10-29-2007


Message 40 of 72 (483266)
09-21-2008 9:27 AM
Reply to: Message 39 by Percy
09-20-2008 1:37 PM


Gastrulation
So your claim is that inter-species embryonic differences are significant between 2% and 8% of the gestational period. This seems unlikely given the short time period, the presence of few structures, and the small number of cells involved, but your welcome to try to support your position.
Cleavage is the stage of division during which the fertilized egg subdivides into hundreds of thousands of separate cells.
At the end of cleavage, the cells begin to move and rearrange themselves in the stage known as 'gastrulation'.
Apparently gastrulation even more than cleavage is responsible for establishing the animal's general body plan. and for generating basic tissue types and organ systems.
British embryologist Lewis Wolpert wrote that "it is not birth, marriage, or death, but gastrulation which is truelly the important event in your life."
It is only after cleavage and gastrulation that a vertebrate embryo reaches the stage which Haeckel labelled the 'first'.
Jonathan Wells writes :"If it were true that vertebrates are most similar in the earliest stages of their development (as Darwin and Haeckel claimed) then the various classes would be most similar during cleavage and gastrulation. Yet a survey of five classes (bony fish, amphibian, reptile, bird and mammal)reveals that this is not the case.Differences among the five classes are evident even in the fertilized eggs.Zebrafish and frogs eggs are about 1mm in diameter; turtles and chicks start out as discs about 3-4mm in diameter that rest on top of a large yolk; while the human egg is about 1/10th mm in diameter.The earliest cell divisions in zebrafish, turtle and chick embryos are somewhat similar, but in most frogs they penetrate the yolk.Mammals are completely different however,since one of the second cleavage planes is at a right angle to the other. Continued cleavage in the other 4 classes produces a stable arrangement of cells, but mammalian embryos become a jumbled mass.
At the end of cleavage, the cells of the zebrafish embryo form a large cap on top of the yolk; in the frog they form a ball with a cavity; in the turtle and chick they form a thin 2-layered discon top of the yolk; and in humans they form a disc within a ball.
Cell movements during gastrulation are very different in the five classes: in zebrafish the cells crawl down the outside of the yolk; in frogs they move as a coherent sheet through a pore into the inner cavity; and in turtles, chicks and humans they stream through a furrow into the hollow interior of the embryonic disc.
If the implications of Darwin's theory for early vertebrate development were true, we would expect these five classes to be most similar as fertilized eggs; slight differences would appear during cleavage and the classes would diverge even more during gastrulation. What we actually observe however, is that the eggs of the five classes start out noticably different from each other; the cleavage pattern in 4 of the 5 classes show some general similarities, but the pattern in mammals is radically different. In the gastrulation stage, a fish is very different from an amphibian, and both are very different from reptiles, birds and mammals, which are somewhat similar to each other.Whatever pattern can be discerned here, it is certainly not a pattern in which the earliest stages are most similar and the later stages are more different."
Embryologist Adam Sedgwick said in 1894 -"it is not necessary to emphasize further these embryonic differences -every embryologist knows that they exist and could bring forward innumerable instances of them. I need only say with regard to them that a species is distinct and distinguishable from its allies from the very earliest stages all through the development."
In 1987 Richard Elinson reported that frogs, chicks and mice "are radically different in such fundamental properties as egg size, fertilization mechanisms, cleavage patterns and gastrulation movements."
Jonathan Wells also says: "Surprisingly, after developing quite differently in their early stages, vertebrate embryos become somewhat similar midway through development. It is this midway point that Haeckel chose as the "first" stage for his drawings.Although he greatly exaggerated the similarities at this stage, some similarities are there."
Jonathan Wells again:
"The actual pattern -early differences followed by similarities, then differences again- is quite unexpected in the context of Darwinian evolution. Instead of providing support for his theory, the embryological evidence presents it with a paradox."
If one were to start with the evidence, then follow Darwin's reasoning about the implications of development for evolution, one would presumably conclude that the various classes of vertebrates are not descended from a common ancestor, but had separate origins. Since this conclusion is unacceptable to people who have already decided that Darwin's theory is true, they cannot take the embryological evidence at face value, but must reinterpret it to fit the theory.
What is true is that embrylogical development across different species has many shared characteristics that are reflective of a shared evolutionary history, and any photographs or diagrams of equivalent embryonic stages across different species very effectively make this point.
????

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 Message 39 by Percy, posted 09-20-2008 1:37 PM Percy has replied

Replies to this message:
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Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 41 of 72 (483290)
09-21-2008 1:37 PM
Reply to: Message 40 by Beretta
09-21-2008 9:27 AM


Re: Gastrulation
That's all very interesting but seems to have nothing to do with Haeckel in biology textbooks. Unless I misunderstand, what you wrote and quoted was about the stages from the bonding of sperm and egg up through cleavage and gastrulation, and Haeckel's drawings were all of stages after that point, so I again think you're posting to the wrong thread. Why don't you propose a new thread, and you can include Jonathan Wells' claims that Darwin and Haeckel believed that evolutionary theory predicts that the very earliest stages of embryonic development should be the most similar.
In the Chapter 13 (Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs) of the Origin of Species is a section on embryology, and in it Darwin states that he is skeptical of the views of Agassiz that are eerily similar to those Haeckel proposed a decade or so later:
As the embryonic state of each species and group of species partially shows us the structure of their less modified ancient progenitors, we can clearly see why ancient and extinct forms of life should resemble the embryos of their descendants,--our existing species. Agassiz believes this to be a law of nature; but I am bound to confess that I only hope to see the law hereafter proved true. It can be proved true in those cases alone in which the ancient state, now supposed to be represented in many embryos, has not been obliterated, either by the successive variations in a long course of modification having supervened at a very early age, or by the variations having been inherited at an earlier period than that at which they first appeared. It should also be borne in mind, that the supposed law of resemblance of ancient forms of life to the embryonic stages of recent forms, may be true, but yet, owing to the geological record not extending far enough back in time, may remain for a long period, or for ever, incapable of demonstration.
Thus, as it seems to me, the leading facts in embryology, which are second in importance to none in natural history, are explained on the principle of slight modifications not appearing, in the many descendants from some one ancient progenitor, at a very early period in the life of each, though perhaps caused at the earliest, and being inherited at a corresponding not early period. Embryology rises greatly in interest, when we thus look at the embryo as a picture, more or less obscured, of the common parent-form of each great class of animals.
In other words Darwin says that while he hopes it will be shown true and clearly understands it would be supportive of his theory, he doesn't think it likely, and he definitely makes no claim that evolutionary theory predicts that this is what we should see.
--Percy

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 Message 40 by Beretta, posted 09-21-2008 9:27 AM Beretta has not replied

  
Beretta
Member (Idle past 5597 days)
Posts: 422
From: South Africa
Joined: 10-29-2007


Message 42 of 72 (483446)
09-22-2008 11:25 AM
Reply to: Message 39 by Percy
09-20-2008 1:37 PM


Re: Haeckel and Darwin
Where did Haeckel ever claim that his drawings in the top row represented the earliest stage of embryonic development?
That was Haeckel's whole point and that is the point illustrated in every textbook where it appears -embryos start out looking pretty much the same (heavily exaggerated and carefully selected to illustrate the non-point)and become less similar as they develop.The fact that he left out the big differences in the earliest stages shows that he purposefully misrepresented the actual picture. The fact that he was charged with fraud shows that I am not the only one that appears to understand the problem. If you don't see the relevance as per your last post then there is really no point in carrying on discussing it. We've said all we need to say.I'd like to get back to the other icons but can't find that topic. Was it erased when we were diverted to this thread or can you direct me there?
Thanks

This message is a reply to:
 Message 39 by Percy, posted 09-20-2008 1:37 PM Percy has replied

Replies to this message:
 Message 44 by Percy, posted 09-22-2008 3:12 PM Beretta has replied
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Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 43 of 72 (483461)
09-22-2008 1:54 PM
Reply to: Message 31 by Beretta
09-20-2008 5:01 AM


Re: 2007 Haeckel's Fraud continues....
I have found the Haeckel's embryo fraudulent scenario in a 2007 textbook
I have seen this from Michael Padilla et al., Focus on Life Science: California Edition. This is published by Pearson, which is the parent company of Maskew Miller Longman.
Is there some specific element about the pictures in the above, and the associated text, that you object to?

This message is a reply to:
 Message 31 by Beretta, posted 09-20-2008 5:01 AM Beretta has replied

Replies to this message:
 Message 46 by Beretta, posted 09-23-2008 7:14 AM Modulous has replied

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 44 of 72 (483466)
09-22-2008 3:12 PM
Reply to: Message 42 by Beretta
09-22-2008 11:25 AM


Re: Haeckel and Darwin
The accusation against Haeckel is that he drew false representations of embryos to make them appear more similar than they really were. That these drawings may still appear in modern textbooks is the topic of this thread.
You're offering a totally different and weird accusation that has Haeckel trying to hide the fact that embryos with eyes and tails do not represent the earliest stages of embryonic development, and you contend that embryos in the earliest stages are very different, that Haeckel knew it, and that he was trying to hide that fact, too. If you really want to pursue this totally odd idea, which apparently originates with Jonathan Wells, then I think you're right, you should probably do it back in the original thread, Icons of Evolution.
--Percy

This message is a reply to:
 Message 42 by Beretta, posted 09-22-2008 11:25 AM Beretta has replied

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Syamsu 
Suspended Member (Idle past 5590 days)
Posts: 1914
From: amsterdam
Joined: 05-19-2002


Message 45 of 72 (483467)
09-22-2008 3:32 PM
Reply to: Message 42 by Beretta
09-22-2008 11:25 AM


Re: Haeckel and Darwin
Heackel had this theory calked the biogenetic law which says that the heritable material develops in sequence, and that things can be added to it at the end, but not inserted in the middle. So ABCDEF can, ABCEF with a missing D can also, but ACBDEF where C is an historical evolutionary addition after B cannot. So the development of the organism to adulthood repeats its evolutionary history
He made the drawings more consistent with the biogenetic law, was convicted of fraud by a university committee, and a denunciation of Heackels findings appeared in Origin of Species. He himself said it was normal practice in science, to make the evidence fit neater.
The biogenetic law was later said by Gould and several historians to originate racial pseudoscience, however the innocent alphabetic theory I explained above seems to have no racism inherent, the link to racist pseudoscience is obviously from natural selection theory.

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