Beyond some point, make the amount of time you;re talking about short enough, and you're clearly no longer talking about evolution at all; you're talking about re-engineering and design changes such as we see from Detroit every year.
An examination of recent evidence involving dinosaurs indicates that the millions of years and tens of millions of years we've been reading about all our lives which supposedly separate our own age from the age of dinosaurs is a bunch of BS.
Readers may do their own google search on "Ica Stones" or check out this link. As I see it, despite the fact of locals producing the things once they discovered that gringos would pay for them, there's basically no possibility that the originals were all fakes.
There is no possibility that the state park systems of Utah and Ontario are both perpetrating the same fraud on the public without even realizing they are doing so. The basic reality is that Indian ancestors dealt with dinosaurs on a regular basis a few thousand or a few tens of thousands of years ago, and not 70 million years ago. Vine DeLoria in particular has no use for Christianity or any other form of western religion, making this line of evidence pretty much immune from being written off as Christian propaganda. Indian legends and oral traditions describe the stegosaur as having red fur and the characteristic saw-blade back and "great spiked tail" which it used as a weapon. The petroglyphs we find around lakes and rivers are warnings, meaning "One of these lives here, be careful"
In fact, aside from the one or two accurate depictions of Mishipishu such as at Agawa Rock, there are other more symbolic pictographs, and yet they all show the dorsal spines of the stegosaur:
Once you realize that the time span separating Ancient Greece, say, from the age of dinosaurs is no more than a couple of times that separating us from Plato and Socrates, then you have to ask yourself a question. Evolution amounts to a claim that all changes in our biosphere occur via processes which we can observe at work in the world today. Given that all of these changes have occurred within the last few thousand or the last couple of tens of thousands of years, then why has nothing resembling macroevolution ever been observed in recorded history? What is it which used to cause such changes which has simply been shut down and turned off in our own age of the world?
Why would it be impossible to evolve flight feathers? The feathers were already there, and flight feathers are a simply modification of them. As for time, archaeopteryx, who already had feathers lived 150 million years ago. There is more time between archaeopteryx and the demise of the dinosaurs (85 million years) than between the demise of the dinosaurs and us (65 million years). Look at all the changes life has undergone in the last 65 million years -- there is plenty of time for feathers, flight feathers and flight to have developed.
You base your claim on there not being enough time for evolution on your (out of thin air) claim that all of history and prehistory is only a few thousand years old, which is based upon the twisting of a few ancient myths and a couple of petroglyphs of uncertain pedigree? You have absolutely no physical evidence to back up your claim and the physical evidence there is completely contradicts it. How wonderful it must be to hold onto one's delusions in the face of reality.