[Titus Quinctius Cincinnatus]

So, as if by magic, in order to prevent evolution, they just stop?

And what has mulism got to do with it.

Er, well, if they can't breed anymore, then they can't pass on genetic heritage.

[From many - one.]

No, the whole point of the invented “macro-evolution” is that changes cannot accumulate far enough that the new popuation has lost its ability to interbreed with the ancestral one.