I still doubt it would have been a "hot" puddle. Or even a puddle at all. Too fleeting, too unreliable. "Warm ocean" is more likely. It took millions, if not billions of years to move to the land, which at the time must have looked just as "extreme" as the Yellowstone hot spring is now.

That in no way contradicts what I said. Extremes are colonized as the last resort, not first.