It would have the Moon's mass added, the Orpheus mass subtracted (assuming an impact formed the Moon). Maybe a wash? But lots more water. So a few peaks & mountain ranges, the rest ocean. And up to 90 degrees of polar wobble over time. Now suppose this Moon-less Earth were currently at the same tilt as our own Earth--about 23 degrees as I recall. <br /><br />I'm guessing life would have evolved. Those benthic vent biota point to life being pretty determined, after all. So we get an atmosphere with oxygen, eventually? The violent climate shifts would be buffered to some extent by the vast ocean, which would also also living creatures to migrate as reguired by that axial wobble. And you could have land animals, though limited by the much smaller available land masses and the lack of shallow continental shelves I'm also guessing. And right now on Moonless Earth there'd be a roughly similar climate, though very Albatross-friendly with big, steady winds in the 40s--north and south. And wouldn't such a place have highly robust life forms, though perhaps nothing very advanced, especially on land?<br /><br />Thoughts?