In 1969, Ford offered a comprehensive model for the diffusion of ceramic production and Formative lifeways in the New World. Although criticized as simplistic, it was echoed by other “unitary” models, such as Lathrap's spread of Tropical Forest culture outward from a lowland South American hearth. Radiocarbon dates suggest that the earliest American pottery appears in the Amazon basin as early as 6000 B.C. However, there is little support for an “ex Amazonas lux” spread of pottery technology. Diffusionary models predict early complexes will resemble one another at first and then diverge over time, but comparative analysis reveals substantial variability even at the earliest time level. Heterogeneity among the earliest complexes indicates several likely hearths for the independent evolution of ceramic production, including (1) lowland Brazil, (2) northern Colombia, (3) coastal Ecuador, (4) coastal Peru, (5) central Panama, (6) southern Mesoamerica, (7) the southeastern United States, and (8) the central United States.