[joshuahedlund]

> Life on earth evolved in the oceans, so the oceans had to exist for eons before life evolved

I can't intelligently contribute to the overall discussion here, but I know one of the most interesting things about the currently understood timeline is the apparent lack of eons between the earliest conditions conducive to life after its initial cooling and the earliest evidence of life. Don't quote me on exact numbers, but within margins of error, as I understand it, it's like in the range of millions of years, not billions (which has all sorts of interesting implications for both the Fermi paradox and religious thinkers) Though, as far as I know, you'd still be correct on the distance to photosynthesis.