This is one of the few "good" things I have seen go through the very busy
supertraining list. I have not looked back through the previous posts to
see what prompted this response but it still strikes me that an evolutionary
approach to health and fitness is unique and considered "fringe".
Message: 5
Date: Thu, 20 Feb 2003 15:50:33 -0500
From: "James Krieger" <[log in to unmask]>
Subject: Re: Evolution, endogenous retrovirus, and pseudogenes
James Krieger wrote:
<<...Modern day apes share a common ancestor....Two
pieces of evidence that I consider to be the "smoking guns" are:
1. Shared endogenous retroviruses at the exact same chromosomal locations
between chimps and humans
2. Shared vitamin C pseudogene between apes and men>>
Yehoshua Zohar wrote:
> I have no idea what you are referring to. Can you please put it in layman's
> terms?
Certainly.
First, let's discuss point #1.
An endogenous retrovirus is a virus that makes a copy of its own genome and
inserts that copy into its host's genome. The HIV virus is an endogenous
retrovirus. The HTLV1 virus is also an endogenous retrovirus and causes a
form of leukemia. Now, if a virus like this inserts a copy of itself into
the germ cell line (the sperm or egg cells), that copy will be passed along
to all future generations of the host. This process is extremely rare.
It's also random, meaning the point in the genome in which the virus inserts
itself varies randomly each time.
Now, imagine a common female ancestor between chimps and humans is infected
with this virus, and the virus inserts itself into the germ cell line. I'm
going to use arbitrary numbers here, but let's say that the virus inserts
itself at position #1000 in the genome. Now, all descendants of that female
will have the virus at position #1000. So, if we find this virus at
position #1000 in both chimps and humans, the only explanation is descent
from a common ancestor, because the chances of a virus inserting itself
randomly at the exact same location in huge genome of two different species
is exceedingly small.
Chimps and humans not only share one retrovirus insertion...they share
seven, all at the same locations. It is practically impossible for seven
viruses to be inserted in the exact same chromosomal locations if it were to
happen by chance. The only plausible explanation is common descent.
Cats give another example of shared retroviral insertions. Small cats, like
domestic cats, share a retroviral insertion with big cats such as lions.
Other carnivores don't have this retroviral insertion.
This also brings up another point about evolutionary theory. Evolutionary
theory, like all scientific theories, are potentially falsifiable. Dogs and
humans don't share a common ancestor (well, at least not a recent one). If
dogs had three retroviral insertions that were unique to humans, then
evolutionary
theory would be falsified. But no evidence such as this has ever turned up.
All
known evidence of shared endogenous retroviruses in living organisms is
consistent with the idea of common descent.
Now let us discuss point #2.
Most species have the capability to make their own vitamin C, so it doesn't
need to be supplied in the diet. Primates do not have this ability. The
reason is that they lack a functional gene that produces an enzyme called
L-gulono-gamma-lactone oxidase (GLO), which is needed to make vitamin C.
However, primates DO have the gene...but a mutation in the gene makes it
non-functional. You and I have the gene to make vitamin C...it just doesn't
work, which is why it's called a "pseudogene." The chances of all the
different species of primates (orangutans, chimps, gorillas, humans, etc.)
all having this exact same mutation is exceedingly small. Again, the only
plausible explanation is that this mutation occurred in our common ancestor,
and the mutation was passed along to all future generations.
I hope this is more clear. Please let me know if it's not and I will try to
illustrate it further.
James Krieger
Graduate Assistant, Nutrition
University of Florida
Webmaster, WSU Strength and Conditioning
http://www.wsu.edu/~strength
Science Editor, Pure Power Magazine
http://www.purepowermag.com
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