That was one point detailed in "Alien Interview".
Given the number of really old civilizations that have been discovered recently, out of place artifacts, and plain old intuition, I believe our history is mostly unknown and quite complicated. Finding humans to be an ongoing college biology experiment wouldn't cause my eyebrows to twitch.
“Finding humans to be an ongoing college biology experiment wouldn’t cause my eyebrows to twitch.”
Yes, we are Genetically Modified Organisms.
We did not evolve. We were modified one stage at a time. Each stage was given time to weed out the weak before the next modification stage. This is why each stage was unchanged for hundreds of thousands of years and then overnight became a newer advanced species out of nowhere and the previous disappeared at the same time. There was no “Gradual change” to it.