Basics of Evolution: Koonin's calculations (Evolution)

by dhw, Sunday, January 03, 2016, 13:55 (3035 days ago) @ David Turell

dhw: For evolution to take place, it's the variations that are essential. Otherwise the process will stick at replication. I would have thought the variety of environments was also essential, since a single uniform environment would limit potential ways of life, and hence the potential variety of species. I'm not sure where this is heading!-DAVID: This is smaller chance than Morowitz 10^40,000 estimate of many years ago. It directly supports my initial response to Romansh's post. Life MUST start with accurate replication. Varying environmental locations offer a tiny hope to improve chances, but no much at the odds quoted.
Of course we are stuck at replication, no matter what the environmental variations!
-There seems to have been a misunderstanding here. I thought Romansh was dealing with the basics of evolution, not with the odds against chance. By ”stuck at replication” I meant that evolution would never have taken place: the first cells would have stayed as they were. The ability to vary is therefore the key to evolution (as opposed to the existence and survival of one type of cell) - but of course you are right that first you have to have the ability to replicate. Environmental variations also seem to me to be an essential factor, for the reason given above. But I wrote that I didn't know where this was heading, and your subsequent exchange with Romansh suggests that his concern is indeed with the odds for and against chance.
 
ROMANSH: dhw...all three are required for evolution to occur.-Agreed.