1578
Sea Level
(imgs.xkcd.com)
Alt text: They're up there with coral islands, lightning, and caterpillars turning into butterflies.
Earth's orbital distance has pretty much always been "perfect" though. It hasn't really changed much since it's formation 4-5 billion years ago.
Unless you mistyped and you're talking about the moon's orbital distance? In which case, it's actually kind of the opposite of what you're claiming. It's estimated that life first popped up pretty close to when the planet and moon finished forming, at which point the moon's orbital distance would have made it appear larger than the sun and probably fully obscure the sun + it's corona during an eclipse.
I did mean the distance between earth and moon, thanks for correcting!
It's the ratio of orbital distances being perfect for total solar eclipses, so it's technically both orbital radii