From: Keith Henson (hkhenson@rogers.com)
Date: Wed 11 Jun 2003 - 03:15:58 GMT
At 05:51 PM 10/06/03 -0700, Dace wrote:
><Keith>
>
> > "Until recently, the interactions that constituted these fields could not
>be
> > identified. However, the discovery of the homologous pathways of
>development
> > has given us new insights into how these fields are established and
> > maintained."
>
>Okay. And what determines the "homologous pathways of development?" Genes
>or fields?
"Homologous pathways of development" = similar pathways of development
between insects and mammals. I.e., body plan genes that "instruct" (via
chemical gradients) a hollow ball of cells into becoming an animal go back,
*way* back, to the common ancestor.
>Whatever answers researchers come up with cannot help but be
>provisional. Every answer merely moves the question back a step.
>Ultimately, the information is either particulate or holistic. Ontogenesis
>is either bottom-up or top-down. Since biochemists are no closer than they
>were forty years ago to providing a detailed picture of how genes build
>bodies, there's no reason not to explore other possibilities. Indeed, this
>is the general trend of contemporary biology.
>
> > I really wish you would use Google more.
>
>You're playing a trick on yourself-- digging up a little sliver of
>information that confirms your prejudice and then imagining you've solved
>the case.
I am citing web locations we can both locate to show that what I understand
from decades of reading details about these areas of science is commonly
accepted knowledge. Also, I don't have the time to type in all the
supporting details, so I cite others who say what I would say if I had time.
> > > > Sample articles
> > > >
> > > > Reference: Scientific American February 1994 PAGES 58-66
> > > > Articles Name- The Molecular Architects of Body Design.
> > > > By William McGinnis and Michael Kuziora
> > > > Jest of Article- Putting a human gene into a fly may sound like the
> > basis
> > > > for a science fiction film, but it demonstrates that nearly identical
> > > > molecular mechanisms define body shapes in all animals.
> > >
> > >If the molecular mechanisms are the same, and the organisms are radically
> > >different, doesn't that demonstrate that organisms are not a product of
> > >molecular mechanisms? This is a huge problem for the mechanistic theory
>of
> > >life.
> >
> >
> > Hardly. "Body shapes" at the level of having a head to tail, left to right
> > and front to back are common from insects to elephants and they all start
> > from a single cell. That the same mechanism (hox genes) lays out the
> > developmental axis only indicates animals with bilateral symmetry had a
> > common ancestor.
>
>It says we have a common ancestor, and there's no discernible reason why we
>don't look like flies.
Your above conclusion convinces me (as to the usefulness of further
discussion).
snip
Keith Henson
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