[VadeRetro]

Sure, cells have mechanisms to "limit change". But so bloody what? Enough change still occurs anyway to drive evolution, since no repair-and-maintenance process is ever 100% accurate.

I can see where the mechanism mentioned limits--as in "somewhat suppresses"--the rate of mutation. I don't see where it would over vast amounts of time completely cap the total number of mutations which do get through. The latter sort of limit was what Patrick was asking Ditto about. Without such a cap, once two populations have speciated, mutational differences just keep on accumulating. Everything we know about mutational clocks says that this idea works.

[VadeRetro]

mutational clocks

Molecular clocks. Time for a break.

[DittoJed2]

You still have to have your vast amounts of time. Scientists today have not observed Macro evolution occuring. They just assume because "micro evolution" or natural variations within a species occurs then macro is possible. If you don't have time, then macro is absolutely out. If you do have time, macro is still a major stretch because it assumes things like personal coming from impersonal, an extremely complex original source out of nothing with the DNA in it to create everything we see, and of course that random chance mutations could somehow organize themselves and form highly complex living beings. I've got a lot of faith, but not that much!