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About 20 years ago, I read a sci-fi short story that was at least 40-50 years old itself, where an alien race has contacted Earth to let the human race know that the alien race is the creator of all life on Earth and the early ancestors of humans. This race is returning because their experiment concerning creating a new planet is over and they have decided that humans have become too dangerous and need to be reassimilated back into the original alien race. The story ends with the race telling humans that all of them will once again become the same "color" and for those who find they are the "wrong" color, not to worry as they will be made into the "right" color of the alien race. The aliens reveal the color as a bit of a bombshell in the last line. I'm hoping this is enough information to go off of. I can't remember the name of the book I saw the story in or the name of the author, unfortunately. I do remember looking at a picture of the author and he kind of looked like Buddy Holly.