As I understand it, just about the only way to generate free atmospheric oxygen, is by photosynthesis. There has to be a whole lot of green plant activity over a long period of time, continually producing new O2 to replace what gets trapped in silicon oxides, iron oxides, you-name-it oxides on the earth's surface.
Detecting atmospheric O2 on some other planet would be a very strong marker for the presence of tons of plant life.
Or so I'm told.
Smart FReepers? Does this make sense?
Having a lot of carbon around gives you a reducing environment (consumes oxygen). The world definitely has both carbon and oxygen.
One thing I do know. Clever wordsmithing does not equal science. It may be rhetoric, it may be poetry, but it does not equal science. Science would care about everything, not just a narrow line of narrative.
And my favorite OEC’er, Hugh Ross, points out quite a few things about the situation of the earth that have made it hospitable to life (something which would have to happen before it could even be the tiniest bit plausible that it would be able to host any kind of “evolution”).
This little speck is quite a rare little speck, to all appearances. We do not have a plethora of worlds in this universe that look enough like this one to live on, Star Wars and fictional places like Tatooine with their herds of blue milk bovines notwithstanding.