Are we "special"?
Paul Crowley (Paul@crowleyp.demon.co.uk)
Sun, 01 Dec 96 00:32:59 GMT
In article <329CF39A.3BD9@scn.org> bh162@scn.org "Phillip Bigelow" writes:
> Also note one other thing in my list: not a *single* question regarding
> how "special" our hominid lineage is. That is because, philosophically,
> I don't believe that our lineage is that "special" in the first place.
[from thread: "An alternative to ST and AAT"]
Why can't this question be scientific rather than
philosophical? While it has nearly always been posed and
answered in a philosophical sense, I can see no reason why it
should not be a scientific one.
Much will hang on the answer. If we conclude that we are
"special" then we will be asking a very different range of
questions about human evolution. We will want to explain
the origin of those features that make us "special".
Phillip has opted for a particular philosophical stance - in
line with the whole profession. I suggest that he (and it) may
well be utterly wrong, and that this is the source of much of
the deep unhappiness that many laymen feel about the answers
(or more precisely, the lack of answers) produced by the
profession. In a sense, we all know that we are "special",
whereas the profession has, almost perversely, decided
otherwise and is determined not to provide the answers we all
want.
Our "specialness" is manifest in the extent of our culture by
comparison with that of animals, but that may not be a good
enough for a scientist. We must be be able to show that we are
"special" in our physiology. This is entirely possible.
Apparently our central nervous system, including our brain, is
governed by ~40,000 genes. Each gene is made of about 600
codons and each codon of 3 bases. That amounts to
40,000 x 600 x 3 which is 72 million bases. It is in this area
that we would differ most from chimpanzees. The major changes
in morphology, mostly those that concerned bipedalism, would
have happened quickly. It is in the CNS that selection
operated over millions of years on millions of mutations to
produce the distinctive H.s.s. characteristics.
No account of human evolution can begin to be satisfactory
unless it addresses the process and cause of these mutations.
I firmly believe that the only possible explanation has to be
based on a very tight localisation in the core habitat of the
species and a highly particular mechanism that explains how all
these millions of beneficial mutations could, in a very short
timescale, spread throughout the entire hominid population.
The traditional view of bands of H/G of about 50 individuals
scattered thoughout Africa (or later: Africa, Europe and Asia)
provides no possible mechanism.
Another way of looking at our "special" nature is that of Prof
Frank Tipler: We've good reason to believe that life is common
throughout the galaxy and the universe. If _intelligent_ life
was present, it would be here already. Since it is not, we
should accept that we are alone; and the likelihood of
intelligence developing on any one planet is *astronomically*
low.
In other words, we could not be more "special".
Paul.
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