I'm not talking about evolution in the traditional sense. That's part of it, but a higher level of evolution exists now that we are capable of modifying our environment. It's hard to explain, but consider what would happen if the earth pushed back in a way we didn't expect or foresee. If chickens and cows became infertile in captivity, we would die off pretty quickly I think and, frankly, I'd have a hard time feeling bad for us. We treat other living things on this planet like shit, so we kind of deserve it. It's not necessarily evolution, but then it kinda is.
Evolution doesn't require long periods of time for significant changes to propagate. Case in point, we could intentionally and artificially introduce selection pressure(s) onto the population to drastically and immediately change our evolutionary trajectory. What if you started neutering everyone who didn't have green eyes? Nature typically plays this game over millennia as you suggested, but we unfortunately have the power to accelerate it.
The other evidence for fast evolution is the bacteria article posted earlier in the thread showing how quickly antibiotic resistance was accumulated in a population. That happened in weeks, not eons. My point is we're disrupting the slower, long term evolutionary trajectory of this planet and that's going to have a long-term impact. How isn't clear, but we'd be naive to not recognize that it's probably coming.