You are correct that common ancestry is not strictly the same thing as
evolution, but I think you are picking nits here, Stephen. I don't think
many people would confuse Terry's use of common ancestry in a context of
evolution as a parent-child relationship.
>SJ>How do you know that "primates all share a common ancestor"? Why
>could not their observed similarities be due to common design
>and/or convergence?
>
>TG>Primates are a separate branch: all member share the deficiency.
>>Guinea pigs are in a completely different branch (independent loss of the
>>Vitamin C "gene").
>
>SJ>How do you know that they were not originally designed without this
>vitamin C `gene'.
>
>SJ>On the other hand, if Guinea pigs can independently lose this
>vitamin C `gene', why could not the primates?
Additional information about the nature of the primate pseudogene that
renders them unable to synthesize vitamin C would be useful for answering
several questions here.
If the pseudogene contained much of the coding information for making the
necessary enzyme, but lacked some crucial regulatory sequence, or had a
fremework mutation, then one might ask why would a designer create a gene
that contained much of the required information, then insured that it wasn't
expressed? Why not just ignore the whole gene?
What are the characteristics and structures of the pseudogenes that prevent
expression of a functional gene product in different primates and guinea
pigs? Do all primates have an identical defect in the gene that prevents
its expression? If so, this would be strong evidence for a common ancestor,
especially if guinea pigs failed to express the gene via a different defect.
Does anyone know the answer to this question?
>
>"Despite these difficulties, many scientists consider molecular
>classification to be not only possible, but, in principle, more
>objective than classification based on visible characteristics.
>Molecular studies have also produced claims having important
>philosophical implications, particularly on the sensitive topic of
>human evolution, because by some molecular measurements chimps are
>much more similar to humans than they are to other non-human primates.
>This degree of similarity may call the importance of molecular
>comparisons into question, because it does little to explain the
>profound dissimilarities between humans and animals of any kind.
There are also quite striking differences between individual humans as well,
even though the DNA information is almost identical. Consider the
difference between men and women based on only one chromosome or the
difference between persons with and without Down's syndrome who only differ
genetically by having 2 or 3 copies of chromosome 21, or more striking, the
Elephant man syndrome which arises from a single mutated gene. I'm not sure
that one can make a simple correlation between genomic relatedness and
morphological similarity.
>
>Because Darwinists take for granted that ''relationship is equivalent
>to common ancestry, they assume that the molecular classifications
>confirm the "fact of evolution" by confirming the existence of
>something which by definition is caused by evolution. They also tend
>to assume that the particular relationships determined by taxonomists
>were "predicted" by Darwin's theory. When these fallacious
>assumptions are made, it seems that a 99 per cent" molecular
>similarity between men and apes confirms Darwinism decisively.
>
>The misunderstanding is fundamental. Darwin did not invent
>classification or reform its practice. His contribution was to
>provide an explanation in materialistic terms of how the categories
>Came about and why the classifiers were right in their instinct that
>the "types" are real natural entities and not arbitrary sorting
>systems (such as a library uses for books). Pre-Darwinian classifiers
>also were aware that humans are physically very much like the
>anthropoid apes. That is why the creationist Linnaeus, the father of
>taxonomy, unhesitatingly included humans among the primates. The
>genetic similarity confirms Linnaeus, not Darwin.
This seems to be a marginal point. Does it really matter who began the
field of taxonomy? It is quite remarkable that genetics provides
significant corroboration of taxonomic schemes.
It tells us once
>again that apes and humans are remarkably similar in some ways, just
>as they are remarkably different in others, but it does not tell us
>how either the similarities or the dissimilarities came to exist.
Yeah ok. But genetic similarities that confirm an evolutionary model are
valuable. The model could have also been falsified by genetic data.
Shalom,
Steve
____________________________________________________________________________
Steven S. Clark, Ph.D. Phone: (608) 263-9137
Associate Professor FAX: (608) 263-4226
Dept. of Human Oncology and email: ssclark@facstaff.wisc.edu
UW Comprehensive Cancer Ctr
University of Wisconsin "It is the glory of God to conceal a
Madison, WI 53792 matter, but the glory of kings to
search out a matter."
____________________________________________________________________________