The study of civilizational collapse is an important topic in anthropology (see, for example, Jared Diamond's book Collapse, Joseph Tainter's work on The Collapse of Complex Societies, and Norman Yoffee's Myths of the Archaic State). In that tradition, a paper Norman Yoffee (of UMich's Near Eastern Studies program) was gracious enough to enlist my collaboration on, and which he then presented at the Santa Fe Institute, is now online:

Collapse in Early Mesopotamian States: What Happened and What Didn't Norman Yoffee and Paul Hartzog

It was presented for The Co-Evolution of Behaviors and Institutions project.