The Great Filter

Robin Hanson (
Wed, 21 Aug 96 15:07:37 PDT

I wrote:
>prokaryotic cells are much less robust to extreme environments, and
>much better tuned to the particulars of Earth now.

but meant to say "eukaryotic" instead of "prokaryotic". Thanks to
John K Clark for pointing this out.

I also wrote:
>guess I need to read up on yet another relevant field

Since then, I found and read:

J. William Schopf (1995) "Disparate Rates, Differing Fates: Tempo and
Mode of Evolution Changed from the Precambrian to the Phanerozoic", in
<i>Tempo and Mode in Evolution, Genetics and Paleontology 50 Years
After Simpson</i>, ed. Walter M. Fitch, Francisco J. Ayalya, National
Academy Press, Washington D.C.

There indeed seems to have been a long period of relatively little
evolutionary change - good new from the Great Filter point of view.
Prokaryotic cells were relatively general and unspecialized, each
species having large populations able to work well in a wide variety
of environments.

This raises an interested thought about future upload evolution.
Maybe humans will continue to be general thinking machines, working
well for many different thinking tasks, and so we won't see that much
radiation into different forms.

Robin Hanson