Early human occupation of Uruguay: Radiocarbon database and archaeological implications

The early human occupation of the territory between the Uruguay River and the Atlantic Coast occurred from ca 11 ka to 7 ka BP. In four millennia, environmental and cultural changes occurred, with better conditions for human life and the end of the megamammal extinction process. The climate became warmer and more humid. The lowlands covered very extensive areas, and the sea level and coastlines changed, producing ecotonal zones with high productivity. This process originated the La Plata River of today.Environmental conditions and social processes are well combined in this successful human colonization. Corporate groups of dynamic hunter–gatherers built an extended social interaction sphere and produced new tool kits for human work. The emergence of variability in lithic projectile points is the material correlation of the technological adaptation to a new environmental condition.The radiocarbon database for Uruguay is adequate, although a little limited for the Atlantic coast. There are several independent lines of evidence toward discussion of hunter–gatherer modes of production and a dispersal model for the Atlantic side of South America. This paper explores information about covariant transformations (in landscape occupation and in way of life) as well as analyzing the role played by the Atlantic coast in human expansion.