Tracy P. Hamilton
Posts: 1239
Joined: May 2006
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| Quote (Daniel Smith @ Oct. 03 2007,02:52) | | Quote (Richard Simons @ Oct. 02 2007,08:48) | It is interesting that, when asked questions, those who accept the theory of evolution answer in their own words, with links to sources, while those who don't accept it cut and paste more or less lengthy excerpts of other people's writings.
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I can't win! First I'm told to bring it back to the subject - which was Schindewolf's take on horse evolution - then I'm chided for quoting Schindewolf!
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You want me to explain Schindewolf's position without quoting Schindewolf?
OK, basically, Schindewolf believed that a lineage's evolutionary path was set from the first saltational event that created that type. He documented what he interpreted as evolutionary patterns throughout the fossil record - which he then used to construct the framework of his "typostrophic theory". This theory consisted of three stages; "typogenesis", which was the saltational evolution of types; "typostasis", which was a period of gradual development in a way that was constrained by the original typogenetic phase; and finally, "typolysis" which was a period of over-specialization that would usually end in the extinction of the species.
He did not believe that anyone was guiding these processes, he believed them to be totally self-contained.
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Grasshopper, now you show comprehension. A kindergardener can cut and paste Einstien's writing - what does that show about their understanding of relativity?
I was talking to my son about his AP history class, and he said that his instructor discouraged the use of quotes. I told my son that I approved such an attitude.
Why is that? It places the burden of what you claim on you. You can't make excuse that because you use some of Einstien's prose that the meaning of that prose read in isolation is something Einstein "said".
Now we can ask: what do we know now about genetics and development that Schindewolf did not? We know about HOX genes, and that saltation (the simultaneous multiple mutation model) doesn't work nor is it needed to explain radical morphology changes.
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Schindewolf was familiar with the relatively new science of genetics:
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I.E. Schindewolf knew as little as everybody else, joined a school of thought that turned out to be wrong. An excellent reason NOT to quote him, eh?
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That does not address the question. The question was "How do these 'internal factors', whatever they might be, get translated into mutations and changes in gene frequences?" In other words, how do the required changes in the DNA (that he could not have known about) take place? What makes a specific alanine change to leucine? Please answer in your own words.
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He believed that these saltational changes took place during ontogeny. He cited the many ontogenetic phases documented in the fossils of ammonites, corals, and other lineages in the fossil record as evidence of this. |
So there is no genetic mechanism that explains why the specific mutations (of which many at once are required for saltation) can be ensured.
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| Quote | Linnaeus first published his Systema Naturae in 1738. How could it not be flawed by today's standards? Hierarchies and evolutionary trees are still hotly disputed amongst those who classify organisms.
You are right that he formed no new hypothesis based on his hierarchy, but he was an adherent to natural theology - so that would be his "hypothesis" I suppose.
The point is that a nested hierarchy was postulated before Darwin's time so how could it be a prediction? |
Hierarchies are hotly disputed? Perhaps at some level, but they are being refined all the time. There is general agreement about the broad outlines and many of the finer details. Could you give an example of a hot dispute in taxonomy?
A nested hierarchy was postulated before Darwin's time? Could we please have a reference.
I think you still have not grasped the significance of a nested hierarchy and are confusing it with Linnaeus' use of a nested hierarchy in his classification scheme. The crucial thing as regards evolution is that it predicts the nested hierarchies will all be the same and that is what is observed. |
You just said Linnaeus used a nested hierarchy to classify organisms. Linnaeus did this more than 100 years before Darwin. Yet you want me to show that a nested hierarchy was postulated before Darwin's time?
As for your second point. Maybe you're right. I'm assuming that nested hierarchies based on morphological characters, or homologous characters, or analogous characters, or genetic sequences will all be different. I haven't seen how they all line up. |
I believe it is I, not Simons who said that Linnean taxonomy is a nested hierarchy.
If you wish to see how they line up, go to www.tolweb.org. There is text that describes the characteristics used for that level of the family tree.
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"Following what I just wrote about fitness, you’re taking refuge in what we see in the world." PaV
"The simple equation F = MA leads to the concept of four-dimensional space." GilDodgen
"We have no brain, I don't, for thinking." Robert Byers
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