I believe that Ellen Frisbie's post Religion and Spirituality in Prehistory is an excellent way of thinking about the difference between paleolithic spirituality and the later organized religion. Before the creation of symbolic language, it would have been almost impossible to communicate the deeply abstract and personal views on "religion." Each would have ideas based on their own life experiances and they would not be able to fully express the details of these ideas to each other. With the invention of language came the ability to spread a single personals ideas, in full, to others.
Ellen's idea of the change between individual focused the group focused is also interesting. at first is seemed semi counterintuitive. wouldn't one be focused on a group while struggling to survive and relying on each other for the hunt, and then self focused in the comparative surety and safety of a city? but no. after greater thought, one is focused purely on survival and how others immediately relate to you in pre-settlement times. once you live in a city, you all relly on each other not just for raw survival, but as a solid identity when you encounter another group. Also, specialization takes away the autonomy of the individual. it needs the group now to achieve it's task. survival is no longer an individual option.