Re: Natural Selection - Question

Greg Stevens (stevens@prodigal.psych.rochester.edu)
Tue, 24 Jan 95 22:20:59 GMT

In <3g3gil$n1l@triton.unm.edu> mycol1@unm.edu (Bryant) writes:
>In article <23JAN199521145209@jane.uh.edu>,
>JAMES BENTHALL <st26h@jane.uh.edu> wrote:
>>In article <bswanson-2201951823040001@macg417d.bio.purdue.edu>, bswanson@bilbo.bio.purdue.edu (Brad Swanson) writes...
>>>In article <rspear.168.0023A01F@primenet.com>, rspear@primenet.com
>>>(Richard Spear) wrote:
>>>> In article <1995Jan22.114417.83388@kuhub.cc.ukans.edu> Brian Doyle
>>><bdoyle@falcon.cc.ukans.edu> writes:

>>>>>If a species forces another species into extinction,
>>>>>i.e. Humans hunting animals, either by pollution
>>>>>or other conventional means, into extinction,
>>>>>Is this considered Natural Selection??

>No; natural selection is about differential reproduction within a
>population. It acts on inidividuals, not species. Extinction is not
>selection in the sense that it shapes a genome.

Really? Now, I have no expert knowledge in this area, but I would have thought
that natural selection acts on individuals as much as individual humans
killing off individual animals acts on individuals. In a situation with
non-humans, one species can push another to extinction through "hunting."
That would be natural selection, so why would it with humans be less so?
Killing things off with pollution is slightly different, but it still seems
like a natural selection process: we change the environment, the environment
changes the survival criteria of the environment, and so natural selection
selects some other species out of the system. We aren't killing them
off directly. But it's the same natural process that happened when the
oxygen producing plants "polluted" the atmosphere with so much oxygen
that many things died... you know, a few million years ago....

>>I would argue that it is not natural merely because with the advent of
>>culture and technology humans have become "unnatural." Natural selection is
>>the differential reproduction and survival of a species...[in a natural
>>environment].Since we have violated the norm of a "natural environment" it is
>>not natural selection.

But we are a part of the natural environment. Differential reproduction is
a function of ability to utilize resources in the environment, and if we
use technology to not only advance our reproduction but alter the
environment in a way that is unfavorable for other species, is it
different than predators killing off prey or beavers endangering fish
specias by damming up migration routes?

Greg