On the one hand, (primitive) life appeared on Earth almost as soon as conditions allowed it. On the other, the early universe — this particular "warm bath" era

On the one hand, (primitive) life appeared on Earth almost as soon as conditions allowed it. On the other, the early universe — this particular "warm bath" era — had approximately zero oxygen with which to make water. Right temperature, just (IIRC, but I'm not certain) zero stars yet, so nothing to make things heavier than what came out of Big Bang nucleosynthesis.