LOS CAMBIOS AMBIENTALES DEL HOLOCENO MEDIO/ HOLOCENO TARDÍO EN EL DESIERTO DE SONORA Y SUS IMPLICACIONES EN LA DIVERSIFICACIÓN DEL YUTO-AZTECANO Y LA DIFUSIÓN DEL MAÍZ

Abstract

in this paper we present a model to explain the initial bifurcation of the linguistic uto-aztecan family, its subsequent diversification of the sonoran/southern branch and the initial diffusion of maize to northwest mexico and the southwest of the u.s. the middle holocene (also known as the altithermal) is aproximately dated to the years between 7500 and 4500 before the present (5500-2500 bce). this period is characterized by adverse climactic conditions during which time the sonoran desert remained almost abandoned. We sugest that these uto-aztecan groups were the first northerners to obtain maize (via west mexico). additionally, we propose that these groups of proto-sonoran-uto-aztecan speakers left their altithermal refuge, located in the foothill/mountain zone of northeastern sinaloa, southeastern sonora and southwestern chihuahua and recolonized the sonoran desert.