The genetic evidence pretty conclusively excludes the possibility of multiple unique evolutionary origins for extant species. I wonder if we could figure out a way to go over that evidence in an on-line discussion. There's a couple biologists here. WK?
I seem to remember a couple of threads on sequence analysis from a while back, I don't know if either of those would be suitable or if we would need a whole new topic.
We could also touch on Doug Theobald's recent work which tried to assess the likelihood of multiple vs. singular origins of life (
Theobald, 2010).
TTFN,
WK
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