Where consciousness arises is not the interesting question. Why is. Biologically, brain structures spend a lot of effort predicting what state they will be in soon. Essentially they are always trying to predict the future. As minds evolved this ability separated from processing what was going on to what could be going on (dreams in more advanced creatures). The next important concept is self versus not-self. If you can change the world around you via intelligence you'll want to avoid unnecessary energy inefficient feedback loops. Being able to model your actions and their effects is the first step of defining 'you'.