Natural Selection and Evolution
Name: Mark D.
Natural selections is based on competition for limited
resources, mainly food. Since almost no one starves to death in developed
countries, what is the primary selecting factor now?
Also, since most of our "best and brightest" are having smaller, more
economical families, while many rural and impoverished people are having
larger families, does this suggest "de-evolution"? I know that poor does
not equal inferior, but it does for most of our capitalist society.
Where can I find more info on this subject?
I think your assumption that natural selection is generally based on any one
thing is wrong...food or other limiting resources. Think of it....every
single protein we have is a product of evolution. From time to time
anything can be a selective pressure and the trait that it finds
advantageous is not so easy to assess. I tend to work backwards...a finch
with a long beak...a red cell with the sickle cell variant, hyoid cartilage
and bones... ...they all have their advantages...the first is food retrieval
one is disease resistance and the last is a complex related to speach.
Peter Faletra Ph.D.
Office of Science
Department of Energy
Natural selection and evolution occur on a time scale of >10^6 years or
more. I would throw out the challenge that given homo sapiens brief
participation in this process(es), that we can even identify what the
selecting factors are. Or that the factors that are operative in the past
several thousand years have anything to do with natural selection.
Some examples: We are the first species in all eon-ic history that has the
technology to wipe ourselves out by nuclear, biological, and/or chemical
means--that is a certainty. But, there are all those issues surrounding
global warming and ozone layer brought about in only the last few hundred
years. Are these but insignificant blips on the time line of history, or are
they our doom. I submit that no one knows.
It is not self-evident that food will be an important factor if genetic
manipulation allows an essentially unlimited supply of food, and the
eradication of disease by "treating" diseases genetically becomes possible,
as it appears it may. These two human interventions could have a large, or
an insignificant part to play on the million and billion year scale. Perhaps
we are just filled with our own self-importance. Perhaps a catastrophic
meteorite will change the whole equation, as it has apparently done so in
the past. Or perhaps a solar belch may end life on earth, but that is a
terra-centered view of existence. On the scale of the Universe our best
guess is that there must be many stellar systems capable of supporting
intelligent life. If earth disappears, we may not even be missed in terms of
the grand scheme of the Universe.
Just a few thoughts for your consideration.
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Update: June 2012