West Mexico has long been recognized as a region of shaft tombs and beautiful ceramic sculptures—both of which were manifestations of a reverence of ancestors and a belief in the afterlife. Today, these traits, among many others, are recognized as characteristic of the cultural development of this region during the period from 300 B.C. to A.D. 400 (generally identified as the Late Formative and Early Classic eras). Recent studies have brought to light evidence of complex social systems that …