THROUGHOUT GEOLOGIC TIME, THERE HAVE BEEN SEVERAL SUPERCONTINENTS. WHEN LIFE ON EARTH WAS SINGLE-CELLED, THERE WAS A LARGE LANDMASS CALLED RODINIA. RODINIA FORMED ABOUT ONE BILLION YEARS AGO, DURING THE PRECAMBRIAN ERA. ON LAND, MICROBES AND BACTERIA COVERED SURFACES. IN THE OCEANS, PROKARYOTIC LIFE SWARMED AND STREAMED. LIFE WAS LIQUID, AND IN MANY WAYS, IT STILL IS. ALL WATER IS THE SAME WATER, MOVING AROUND IN PERPETUAL SWIRL INSIDE US, INSIDE ROCKS.