Edit- I was thinking about this today.. Since animals are mobile, perhaps the brain has evolved because it's beneficial to one of our survival methods- flight. If an asteroid were headed towards Earth, bacteria would have to adapt to the new environment in order to survive, whereas we could use our brains to move. Can the differences between how plants and animals react to an environmental change be compared to how intelligent life versus say, bacteria, would react? Is consciousness in life forms just a structure, like eyes or a mouth, but one that lets them have greater mobility across the universe?