u/LordOfPies

Just a weird random thought

So I recently heard Brian Cox talking about the Fermi Paradox, and he mentions that we might be alone in the universe as far as intelligent life goes because of the rare earth theory. Very briefly put, Earth has had complex life sustaining conditions (beyond bacteria) that have gone uninterrupted for 4 billion years, without the presence of several truly major cataclysmic events like the cosmic rays or earth destroying asteroid hits.

The only one that comes close to that was the asteroid that wiped off the dinosaurs 66 million years ago. It wiped out the dinosaurs and basically reset Earth’s ecosystem. That allowed mammals to take over, and eventually led to humans.

But it got me wondering:

Maybe the “rare earth” conditions are even more rare because we were hit by that asteroid. If that asteroid never hit, would intelligence like ours still have eventually evolved anyway… or did we basically need that extinction event to “clear the way”? Or did it “speed things up”, as if, if it didn't hit, maybe intelligent life would have taken much longer since it would have had to form in reptiles, avian dinosaurs or another species.

Were dinosaurs basically blocking the path for something like humans? Is intelligent life something that would probably show up eventually no matter what dominant animals existed? (Possibly much later?)

How “necessary” are mass extinction events in the story of intelligence?

I know this is counterfactual, but I’m curious how scientists actually think about this—whether humans were kind of a lucky accident of a reset button, or just one inevitable outcome of evolution given enough time

So going back to the Fermi Paradox, in the case of earth, having a major cataclysmic event like the asteroid hit in the right timing may have been a necessity for intelligent life to "speed it up" given the conditions we were in. So we are like, super duper rare