Since the question is about the extinction(ie the death of ALL humans)...if we are including anything from space under natural disaster, then my money is on that.
As i see it space has way more ways to get us, where as all mankind being wiped out by humans only has 1 really plausible method: A huge unforeseeable catastrophic accident.
It would have to be something Physics related since we are talking of something so powerful it would get everyone everywhere in nearly the blink of an eye. I rule virus' out because virus' takes time to spread and there would always be people smart enough to hole and keep working on a cure ala Will Smith in I Am Legend.
As i see it space has way more ways to get us, where as all mankind being wiped out by humans only has 1 really plausible method: A huge unforeseeable catastrophic accident.
It would have to be something Physics related since we are talking of something so powerful it would get everyone everywhere in nearly the blink of an eye. I rule virus' out because virus' takes time to spread and there would always be people smart enough to hole and keep working on a cure ala Will Smith in I Am Legend.
