Individual evolution vs population evolution: I'd find it easier to believe a few individuals possessed the rare alterations at different times in the chain that eventually lead to a true species rather than a mass of creatures simultaniously changing in the same way without something violent enough happening to kill them.
You didn't understand what I wrote. What I wrote was "evolution happens to populations, not individuals."
Not "evolution happens to all the individuals in a population simultaneously." That's not what I said, because that's not what happens.
Individuals don't evolve. They don't change, except through the normal course of maturation through life stages. They're born with all the adaptations they'll ever have; they don't generate new ones on the fly, on demand.
You need to look at populations the way biologists do. Imagine a population of ducks, or something. They're all standing there in the barnyard, and they all have their own set of genes. Ok?
Now, imagine the ducks are gone, or are just there in outline. All you're looking at is the genes. You're looking at a barnyard full of alleles of those genes. Which individual has what allele isn't relevant; what you're looking at is the gene pool of the population, and how many copies of each different allele are sitting there in your barnyard.
If you could fast forward in time, you would see, for each allele, its number wax or wane, until either that allele was evenly spread throughout the pool to every individual, or it was eliminated from the population. And you would see old alleles turn into new ones, be changed.
That's evolution, and it's happening to the
population, not any of the individuals. Individuals don't evolve, no matter what you've seen in the
X-Men.