Re: Rare Earth Debate Part 5: Elusive ET
Thanks for part 5
I think that comment of McKay's about rapid evoloution of life without PT is a Red Herring. That phase of planetary evolution can only last for a few tens to hundreds of Ma. After that, everything gets locked up and even if the bugs did evolve fast to the oxygen stage, they're still starved of precious nutrients and the atmosphere begins to decay. Plus, they're still only bugs unless you posit orders of magnitude faster evolution than on Earth.