In Maya Political Science: Time, Astronomy, and the Cosmos, Prudence M. Rice proposed a new model of Maya political organization in which geopolitical seats of power rotated according to a 256-year calendar cycle known as the May. This fundamental connection between timekeeping and Maya political organization sparked Rice's interest in the origins of the two major calendars used by the ancient lowland Maya, one 260 days long, and the other having 365 days. In Maya Calendar Origins, she presents a provocative new thesis about the origins and development of...