The author says we used to think that increased agriculture moved humans from a nomadic society to one using cities. An archaeological dig in Turkey makes those assumptions suspect, though.
The dig's implications lead him to conclude that wonder at the changes in the natural world led to religion. The earth's warming after the last ice age led to this wonder. The author suggests that gathering together for worship created a need for food. This in turn led to increased farming and cities.
- The Birth of Religion article (National Geographic)