Oops, sorry, that was in the other big thread. Although nobody had answered it there, either.
Do you have a source on dogs being bred from a starting population of 50 wolves, or did you just pull that number out of your hat?
I wish I could find a good source on the extent of human diversity. What made me think of this point was actually a Discovery channel show I saw a couple years back. Some scientists had used some clever sort of genetic analysis to determine that the human population had most likely gone through a population "bottleneck," in prehistoric times. But their idea of a "bottleneck" was more like 10,000 individuals, not <I>two.</I>
It's just common sense. You can't take two individuals, have 'em breed, then have their <I>kids</I> breed, etc. and so on, for a couple hundred incestuous generations, and get the population and genetic diversity we've got.
And unless you are willing to provide historical or anthropological evidence to show that the human species has "degraded" from some original state of perfection, I'm going to give the idea exactly as much credence as I give any myth.