Re: The Great Filter

From: Twirlip of Greymist (phoenix@ugcs.caltech.edu)
Date: Wed Aug 21 1996 - 21:39:03 MDT


On Aug 21, 2:55pm, CurtAdams@aol.com wrote:

} Actually the ribosome RNA sequences indicate eukaryotic and prokaryotic life
} are approximately equal in age. Eukaryotic life, with its hodgepodge of
} interacting and varied systems and vast amounts of apparently useless baggage
} is a much more plausible model for spontaneous self-organization a la
} Kauffman than efficient, minimized prokaryotic life.

Um. I'm not an expert, but I'm not sure how useful rRNA is here. One
model of eukarya is that a magnetobacterium swallowed an archaean and
turned it into its nucleus, with similar swallowings for famously the
mitochondria and chloroplasts. I mean, I know rRNA is used for the
phylogenetic trees but I'm not sure how it would distinguish here. Also
that there may be some assumptions of uniformity, and I'm not sure how
robust the method is to some past deviation we couldn't see.

And given that eukarya certainly _do_ contain prokaryotic mitochondria I
cannot see the validity of the "self-organization" statement. Prokarya
possibly require an RNA replicator hijacking a fat globule, or
coacervate. Eukarya build on that.

Merry part,
 -xx- Damien R. Sullivan X-) <*> http://www.ugcs.caltech.edu/~phoenix

Leave Calvin and the Bible to the parish o' Dunbar.
Give a blind man back his eyes to find the brightest o' the stars.
Then lead him to the altar of a better God by far
In the vale of the redwood cathedral.



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