On Fri, 22 Sep 2000 10:01:45 -0400, Ben Balzer <[log in to unmask]>
wrote:
>.. As for U-turns- they are very difficult- as you
>say, it is easy to lose a gene, but to reproduce it is awesomely difficult.
>
>For a 30 amino acid protein (takes a 90 DNA sequence) to be randomly
>produced - with 4 different DNA codes, this makes 4 to the power of 90= 10
>to the 54 = a billion billion billion billion billion billion. Makes the
>odds of being hit by an asteroid look good.
It appears to me that most genetic changes change more the adjustments
of shape and extent in which already existing metabolic mechanisms are
used.
We share 84% of our genes with cows.
We have identical genes to over 93% with mice
and some 97% idendity with chimps.
The primary mammal metabolism, particularly which enzymes are used,
which nutrition pathways are possible, how cells are built and
destructed
is not so much different.
But some genes -which weren't necessary for long- may have been *lost*
during the time. Like the ability to synthesize Vitamin C or some
function
with folacin (as you noted). As you outline, the probability that a
*new*
enzyme or smallest components of our digestion apparatus emerge, is
*very*
small.
What does differ significantly is the size of various organs.
Brain of course which increased our intellect and glucose requirement.
Muscles, liver, kidney, pancreas, gall have smaller differences
and tend to adapt short term and to individual needs.
The length of various parts of the gut (intestine, ileum, stomach)
have been stressed much by both the veg*an and meatatarian believers.
As gut length doesn't change during the life gorillas, cows, cats and
humans are variedly fit for varying food sources. A longer gut is
capable to
house more of the symbiont bacteria which break down cellulose walls.
Longer guts exploit heavy cellulose food (like leaves) better than
shorter
guts. Shorter guts protect better from putrefying bacteria in quick
digested
food. I leave it to scientists or to some charts where humans should
be
classified in. Humans are somewhere between gorilla and cat, but much
nearer
to gorillas as far as i recall.
Maybe someone can provide a chart with gut lengths of more animals as
just
wolfs and sheep (e.g. cats and chimps).
But in general all these animals (and our animal body) are capable to
rely
on the most food sources. Cows *can* be fed meat (and are), chimps eat
baby
monkeys.
As a conclusion of all this, I think it's wise to keep more attention
on the
*real* physiological constraints.
1.The essentials (vitamins) are known most effective constraints.
The most striking field in this area are for me the energy vitamins -
the vitamins necessary to metabolize food fuel (Vitamin b1, b2, b3).
They are *guaranteed* in all paleolithic and pre-industrial food
items.
And unavailable in *most* food items of today.
2.The varying capability to cope with disturbing substances (toxins)
too.
Cats are capable to deal with purin and botulinus, humans less or not.
Some birds can easily deal with phytin, humans much less.
Btw.... this was from the paleo-religion thread....
Something I'd like to say.
I personally never felt a big contradiction between creationists and
evolutionists. If God has created the earth why shouldn't he do it
by means of evolution. And the 7 days... What is a day of God anyway?
Especially before the sun and earth was created, which defines a
"day".
Cheers
Amadeus S.
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