"If". What if the substance is abundant? I suspect (here again, just an intuition) that our planet is actually exceptionally good, not for life to appear, but

"If". What if the substance is abundant? I suspect (here again, just an intuition) that our planet is actually exceptionally good, not for life to appear, but for evolution to occur. One theory of abiogenesis supposes that life started in hydrothermal vents, in conditions that are very far from what is considered "habitable" for the current life (very hot water, high pressure and, IIRC hard acidity) Maybe these are the only conditions for life to start, but does not offer a lot of room for improvement. Maybe there is just so much things you can do to efficiently colonize interstices of volcanic rocks. But then you have a whole host of conditions offered to you: a gradient of temperatures and pressures, light, storms, changing currents, varied geology. And then later on, dry lands, of a varied range of temperatures. If the conditions for abiogenesis and evolution to occur are very different, Earth could be unique in that aspect: how many oceanic planets on a stable orbit will still have days, tides, seasons, storms AND hydrothermal vents of the correct type to generate life?