From: Billy Brown (bbrown@conemsco.com)
Date: Mon Jan 25 1999 - 09:53:08 MST
Scott Badger wrote:
> Huh? If all lfe is destroyed by the GRB, _and_ life starts up again on
> the planet, a few hundred million years isn't going to be enough
> time for space faring levels of intelligence to arise, is it?
>
> Surely this fact did not escape him. So what aspect of his theory am
> I not getting?
A GRB won't destroy *all* life. It would cause a mass extinction, killing
all land-dwelling life on one hemisphere of the planet and (through indirect
effects) a lot of other life in other areas. It might or might not manage
to kill off land animals on the shadowed side of the planet (by suddenly
destroying the ozone layer and atmospheric composition). In any case, a
great deal of life will survive in the oceans.
If GRBs occur every few million years, complex animal life probably can't
evolve. If it happens every few tens of millions of years, it evolves but
doesn't have time to get very far. According to the theory, the gap between
successive bursts has only recently become long enough for life forms like
us to evolve.
I'm not sure if I buy all this or not.
> Besides, Jay Gould once stated that the contingency based character of
> natural selection was such that if evolution were replayed millions of
> times, intelligence would not appear on the planet. This was in
> stark contrast to my up-till-then cherished theory that attributes such as
> increased levels of awareness, neural complexity, and consciousness would
have
> good survival value. Point being, Dr. Annis seems to assume that
> if life appears on a planet, intelligent life is a highly probably
outcome.
> Gould assumes the opposite.
Combining 'rare intelligence' with GRB extinctions would certainly make us
rare, though.
I don't think I but Jay Gould's idea, however. Look around. Recently
evolved types of life (mammals, avians) seem to be much smarter than older
ones (reptiles, fish). There are lots of unrelated species that are smart
enough to make people worry about whether they are sentient or not (apes,
whales, dolphins, elephants, and a couple of species of birds). The
combination of tool use, intelligence and a capacity for large-scale social
organization might be unusual, but there seems to be a clear trend towards
increasing intelligence.
Billy Brown, MCSE+I
bbrown@conemsco.com
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