I was wondering, what would it be like if instead of an oxidizing atmosphere like earth has, if an ecosystem had a reducing atmosphere instead? My professor told us that a system like that could be chemically/biologically possible. But didn't explain how. What would interaction between organisms and their reducing surroundings be like? How would these organisms survive?
I know that this means there would be an extreme lack of oxygen, and as far as I can tell, most everything on earth needs oxygen to survive. There are complex organic molecules that can be created in a reduced atmosphere, right? What are they?