I suspect that had the answer been that the sky was a different color a bazillion years ago, the followup question would have been something like "But how could chlorophyll have evolved when the sky was a different color?"
Reductionist and proud of it.
Being ignorant is not so much a shame, as being unwilling to learn. Benjamin Franklin
Chase after the truth like all hell and you'll free yourself, even though you never touch its coat tails. Clarence Darrow
A person who won't read has no advantage over one who can't read. Mark Twain