No Moon, no life on Earth, suggests theory: “A billion years later when life is thought to have arisen, the Moon was still much closer to us than it is now. That, plus the Earth’s much more rapid rotation, led to tidal cycles every two to six hours, with tides extending several hundred kilometres inland, says Lathe. Coastal areas therefore saw dramatic cyclical changes in salinity, and Lathe believes this led to repeated association and dissociation of double-stranded molecules similar to DNA.”