So are these mutated individuals significantly and morphologically different from the rest of the group, as the fossil record indicates?
Or is this one-individual-in-several-thousand-generations minutely different from the rest of the herd?
In the former case, the odds of a male and female mutating similarly and simultaneously is effectively zero.
In the latter case, we have the problem of the abscence of transitional forms in the fossil record and the lack of any plausible mechanism for the development of staggeringly complex biological systems.
Or is this one-individual-in-several-thousand-generations minutely different from the rest of the herd?
The mutations within any given generation are never going to be so great as to prevent the individual with them from mating within his population -- otherwise the mutation immediately disappears from the gene pool. The mutation may be something very tiny, such as a different colored spot on a wing, or it may be something not physically noticeable, such as the ability to digest cow's milk. If the gene aids in survival it will eventually (several generations later) come to be possessed by the entire population. I don't quite understand your inability to grasp this fairly simple concept; it's almost as if you are poking around attempting to find some flaw or chink that can be exploited to allow you to maintain a belief that God zapped it all into existence in situ, instead of the somewhat messy-but-effective method of mutation and selection.
Gore3000's reticence I can understand. He's dug himself a hole so deep with his constant bearing of false witness that he's got to prove to God that it was all in a good cause if he's to avoid problems once he shuffles off this mortal coil. You, on the other hand, have up until just a short while ago, evinced an open mind with regards to learning what the Theory of Evolution really means. This was similar to a situation we had with a young fellow about a year ago named PatrioticTeen. He started off asking fairly intelligent questions about the theory and seemed to be picking up on what it really meant rather than what he'd been told it meant, but then suddenly he began to parrot the standard fundamentalist line that evolution was evil, satanic, atheistic and caused tooth decay -- it was almost as if someone had flipped a switch. I don't want to see our conversations here descend to such a level.
Besides, with a tag like Aquinasfan, you've got to be a thinker...