More about how evolution works; stasis (Evolution)

by David Turell , Wednesday, October 14, 2015, 15:42 (3326 days ago) @ dhw


> dhw:The mystery is not stasis but innovation, and this might well happen if there are changes in the environment that allow for improvement. That doesn't mean innovations will always happen when the environment changes, and why should we expect it to? Each innovation has to take place within individual organisms, and that will require exceptional individuals. Once the “invention” works, it establishes itself, and if it's optimal, it won't change (= stasis).-All we know is environmental changes cause modifications, which are reversible when the environment changes again. We do not know how complexity advances, as in the appearance of humans, and also illustrated by the non-change in bacterial complexity.
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> DAVID: Comment. Voje is struggling for an answer that sounds real. We know the Earth has had enormous changes as evidenced by hot periods ( palms in the Arctic), glacial periods, and continental drift, and so many species show no change. they arrive full-blown and disappear millions of years later looking the same, or are still here laughing at us because we do not understand the process of evolution.
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> dhw: “...and so many species show no change” is not really logical: if the environment changes, you would expect species to change, and in many cases they do - the biggest change being that they die! Others, however, adapt. The mystery is why new species arrive. See above.-We've had glacial periods, hot periods, etc, and species survive unchanged. They must be perfectly adapted to total survival. This does not explain increasing complexity which must be a very specialized process, relegated to only certain groups of organisms. Smells of a designed evolutionary plan.