Does Neo-Darwinian evolution require change ?

Faith used to back her affected agrument by incredulity with specious appeals to "genetic meltdown". Her favorite example was the amazing cheetah.

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He's had it rough as the poster-child for reduction of genetic diversity. Due to depopulation, isolation and inbreeding his genetic variability is so low that skin grafts between unrelated animals do not result in immunological rejection! And so on, there are a lot of lovely fables in this area.But contrary to popular belief, this is nothing new for the cheetah. It began thousands of years ago, toward the end of last ice age, in a fairly ordinary genetic bottleneck. And as result of this process, the cheetah has become the least "feline" of all the big cats. In another million years or so, he may look something like this: Or this: The misadventures of these fellows actually provides the key to your whole puzzle. You see, when the gene pool is large and conditions remain stable, the overwhelming majority of even the effective, non-neutral mutations are quickly lost in the shuffle. They are outnumbered and as they provide no selection advantage, there is no reason for them to be preserved.When the gene pool is greatly reduced however, either due to large-scale changes in the environment in terms of selection factors or to the spreading out of outliers of a population into a new area or niche, this changes. The cow's primary source of genetic diversity is, other cows with somewhat different genes. The cheetah's, though, is mutation. Each new trait produced by mutation is valuable to a reduced species and likely to be preserved, resulting in large-scale morphological changes over a relatively short period of time. Still in the high thousands and millions though.And this is the main factor underlying Gould's "punctuated equilibrium". For ten million years, everything is fine. Then things change; and when they do, things change. Eerie. But not mysterious, simple statistics. Message 18As I've demonstrated, Paul has already given you the answer to both longterm stability and rapid change. Why can't you see it? Cleopatra.