Good point. Perhaps we ourselves originated from von Neumann probes in the form of single cell organisms, flung into space in all directions by a long gone, hig

Good point. Perhaps we ourselves originated from von Neumann probes in the form of single cell organisms, flung into space in all directions by a long gone, highly developed civilization? We don't know how long intelligent life lasts on average. Looking at our current trajectory i'd say chances are that technical civilizations are rather short-lived. PS The Paleozoic began with the Cambrian explosion 541 million year ago, that's quite a long timespan with intelligent life (not a technical civilization, however) even in galactic timescales.