Because the discovery and control and use of fire seemed to have played a big role in our evolution, I came to think how that would play out on a world were the atmosphere did not contain oxygen. 

Assuming live is possible without (great quantities of ) oxygen - oxygen being a poison - how would the dominating species of a world without oxygen have evolved? Are there any other gasses that can make a fire burn and could likely be present in such an alien atmosphere? What would they burn? Would there also be some sort of plant-matter? Would it be possible for any species to evolve to more or less our level without the controlled use of fire? Or would that simple not work and would they remain 'animals' forever...?