Hal Finney wrote:
>> My thought is that this indicates that evolution of complex SAS is
>> exteremely unlikely, a rather pessimistic view compared with the
>> optimism of Sagan, or for that matter most Alife theorists.
>
>You might want to take a look at Robin Hanson's paper at
>http://hanson.berkeley.edu/greatfilter.html, specifically the section
>http://hanson.berkeley.edu/greatfilter.html#biology, which identifies as
>many as four separate "hard steps" in the evolution of intelligence, of
>which the last is the Cambrian explosion. Robin also proves that hard
>steps should be roughly equally spaced regardless of their intrinsic
>difficulty.
The up to date and technical discussion of this is in
"Must Early Life Be Easy? The Rythm of Major Evolutionary Transitions"
at
http://hanson.berkeley.edu/hardstep.pdf or .ps
Robin Hanson
hanson.domain.name.hidden
http://hanson.berkeley.edu/
RWJF Health Policy Scholar FAX: 510-643-8614
140 Warren Hall, UC Berkeley, CA 94720-7360 510-643-1884
Received on Tue Nov 17 1998 - 09:01:54 PST