Was: Woese Now: Origin of life and Karl Popper

[Curtis Clark]

At 08:15 PM 10/20/97 -0200, Thomas Schlemmermeyer wrote:
>So what about this tree of evolution, formulated by Popper in
1974?
>Is it today possible to decide how many different forms or
groups exactly gave rise to evolution?

It is clear to me that all organisms alive on earth today have a
common origin: they all share the synapomorphy of the genetic
code. I've heard no evidence that the actual genetic code is in
any way adaptively superior to any other possible genetic code,
so parallel evolution of identical codes seems unlikely. Thus,
the parsimonious explanation is that all living organisms come
from the first organism (or population of organisms) to have the
genetic code that we know today.


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