Haeckels' Drawings Part II

And indeed those textbooks which did contain exact reproductions of Haeckel's drawings were using them in a historical context to discuss the development of evolutionary thought including dead ends such as Lamarckian inheritance and recapitulation, with perhaps one eception.TTFN,WK

I think you have hit the nail on the head here. It was neat and catchy and people thought that it would explain everything, to the point where they ignored the numerous exceptions which kept turning up. But catchiness of a slogan, or an idea, is not enough to sustain it permanently. You didn't for instance read Gould's 1977 book 'Ontogeny and Phylogeny' which gives a very detailed history of the recapitulationist movement and its subsequent fall from grace and eclipse by those interested in the actual mechanics of development. I'm not even sure what this encyclopedia is talking about, the biogenetic law is very specifically Haeckel's theory. In fact given that the encyclopedia talks about humans being more advanced in the evolutionary process than fish, a pretty untenable claim without distinguishing between ancient and modern fish, I'm thinking that I won't be going to the Columbia Encyclopedia as a source of knowledge. No, it suggests the still highly credible notion that the embryos of fish and humans display a number of highly similar features, including the developing pharyngeal structures. Well it would be since they are both based on the Columbia Encyclopedia.Since the dictionary definition is just that it can hardly be expected to provide the sort of information one expects from an encyclopedia. This is simply your own interpretation, the 'modifications' to the relationship between ontogeny and phylogeny in Haeckel's theory and that of modern evolutionary and developmental biology are considerable. This is only true if you believe that to explain these all evolutionists do is say, "it evolved that way". The problem is that they aren't explained by design. Certainly 'they were designed that way' is given as an explanation, but it explains no more than simply claiming that 'Goddidit' but we can't understand his reasons for doing it. Modern evolutionary theory has a mechanism for both the genesis of evolutionary features, in terms of mutation, and the spread of such feature through populations and the selective maintenance of specific populations or sub populations on the basis of these features.What exactly does 'Design' do to explain anything? What mechanisms does it propose? How was a 'designed' trait brought into being? The best answer I have ever come across are those such as Randman's interference at a quantum level, for which there is absoloutely no evidence, which might at least be amenable to some sort of experimental validation.TTFN,WKThis message has been edited by Wounded King, 08-03-2005 05:10 AM

Or so you claim. In fact Haeckel's theory has been entirely discredited, what is not discredited is that there are numerous similarities between developing embryos and that enumeration of these can produce phylogenetic data consistent with that from other sources. Similarly analysis of the genetic basis of development is highly consistent with the mechanisms held to be important in evolutionary biology. Well that is because all of those online dictionaries take the definition from the same hard-copy encyclopedia, so of course they are going to be the same. That is like the Bellman's fallacy, if the same erroneous material is repeated three times then it must be true.How on earth can you claim that one article in an encylopedia, no matter how often it is parroted, is somehow the 'official representation'?PaulK is welcome to his own opinions, but he seems to be agreeing with me that Von Baer's theories should not be connected to the term biogenetic law. More literal rather than tangible perhaps, to the point where it was clearly wrong, embryonic human pharyngeal arches and pouches never resemble the adult gills of fish. But of course this wasn't neccessarily an ongoing assumption it was an assumption which Haeckel himself made but not one that he was neccessarily simply elaborating, I don't know the exact origin of the usage of 'gill slits' to describe the pharyngeal pouches in all vertebrates, do you? Isn't Webster's a dictionary rather than an encyclopedia? The only encyclopedias that Webster's seem to offer are an encyclopedia of literature and the Encyclopedia Britannica, which doesn't have the same article.

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biogenetic law

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also called Recapitulation Theory, postulation, by Ernst Haeckel in 1866, that ontogeny recapitulates phylogenyi.e., the development of the animal embryo and young traces the evolutionary development of the species. The theory was influential and much-popularized earlier but has been of little significance in elucidating either evolution or embryonic growth.

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Unfortunately I don't have access to the full article. You can still stay it, but it still isn't true and it was never valid to say it, although it may have been thought to have been. But you haven;t posted anything actually refelcting the current status of evolutionary-developmental biology, so all you are doing is producing what Haeckel said and then claiming that that is effectively still what is being said today. Even the one clear distinction that is made in the encyclopedia article, between embryonic and adult stages, is such a significant one that it completely changes the character of the proposition. Well if you claim that all similarities are a result of 'design' then sure, but that is only a tenable argument if there is any reason to favour design over simply evolution, which there isn't. It doesn't stop being evidence consistent with evolution just beacuse you also claim it is consistent with design. Wow, how strange that in the couple of hundred years we have been studying evolution, and the hundred or so we have had some reasonable grasp of genetics and the 60 or so we have had some understanding of the molecular basis of genetics we haven't yet observed any radically morphologically novel species evolving.Do you have any idea how weak an argument that is? What we do see is all these mechanisms in operation and acting to produce discrete species and produce differing morphologies. We also see a number of patterns reflected in the genomes of various animals which form a basis for larger morphological differences and in a number of case seem linked to such evolutionary mechanisms, i.e. gene duplication and neo-functionalisation. As easily perhaps, but not as well.TTFN,WKP.S. Could you fix the quote tags in your post, at the moment it is very confusing.