Re: Evolution: A few questions

Peter Ruest, wrote:

> The spontaneous generation of information by means of natural selection
> of random mutations does occur, but each such step of selection is just
> a yes/no "answer" of the environment to the "question", "Is this ok?" of
> the organism.

I believe it is entirely possible that environment factors play an active
role in eliciting change in the genetic mix upon which selection can act.
This was in my book:

Antibiotics experts have long recognized the adaptive capacity in microbes
that have developed immunities to the drugs designed to wipe them out.
Penicillin was introduced in the early 1940's. Soon after the infectious
disease-causing bacteria were exposed to penicillin, they began producing an
enzyme called beta-lactamase, which destroys penicillin and related
antibiotics.

In the early 1980's broad-spectrum beta-lactams were launched to kill
drug-resistant bacteria. But the bacteria responded by mutating the gene
encoding its defensive enzyme so that it now can ward off these drugs too.
George Jacoby, a specialist in infectious diseases at Massachusetts General
Hospital, remarked, "Bugs are always figuring out ways to get around the
antibiotics we throw at them. They adapt and come roaring back."

Researchers also know that certain genes have a DNA repair function. They
even know there are several DNA repair pathways. Some genes are capable of
repairing DNA without making error, while other genes, in their words, "are
prone to make mistakes." It is suspected strongly that these latter genes
that repair DNA with new coded information cause mutations which contribute
to genetic change.

Recent outbreaks of tuberculosis have fostered new research into this
disease. It has been demonstrated that due to a mutation, the bacterium
causing TB is now resistant to isoniazid, the main drug used in treatment.
Thanks to a hard-working research community, a genetic basis has been
identified for TB drug resistance.

What has been recognized already at the level of the microbe can also be
witnessed at the highest levels of life. Among human populations, skin
color affects the absorption of vitamin D from sunlight. Higher latitudes
have decreased sunlight, lighter skin improves absorption, and
lighter-skinned peoples are found at higher latitudes.

Sickle cell anemia is a genetic disease affecting some black populations.
This gene is recessive and appears to afford enhanced resistance to malaria.
The sickle cell trait may have been a genetic response to an environmental
danger.

There is an increased risk of inheriting the genetic disorder, Tay-Sachs
syndrome, among Ashkenazi Jews, and this has been traced to Polish ghettoes
in World War II. Though, like sickle cell, the disease is fatal where one
inherits the gene from both parents, yet the Tay-Sachs gene has been
correlated to an increased resistance to tuberculosis, the scourge of the
ghettoes in those days.

Researchers have begun preliminary investigations in this general area of
inheritance affected by environmental factors. A conference was held in
Pittsburgh in September, 1992, on "male-mediated toxicity."

After 3 days, the consensus was that there is an

urgent need for studies to elucidate mechanisms

underlying tantalizing evidence that many different

types of paternal exposure induce changes in sperm

or semen that could affect children's health.

In the not too distant future we may discover how adaptive genetic mutations
may be shaped by environmental forces, something that was postulated an
early pioneer of evolution theory, J. B. Lamarck.

Dick Fischer - Genesis Proclaimed Association
Finding Harmony in Bible, Science, and History
www.genesisproclaimed.org
Received on Mon Jun 14 14:48:58 2004