The sky on earth: first archaeoastronomical approach to the pre-hispanic mounds of the uruguayan lowlands (Rocha, Uruguay)

Abstract

The development of different mound architectures in South America appears in distant ecological regions and with clear ethnic differences. We could highlight the Amazonia, the Moxos lowlands, the Paraná delta, the Uruguay and southern Brazil wetlands and the southern Atlantic coast and sierras. It is generally understood that this phenomenon materialized the establishment of communal ways of organization, the emergence of social complexity and the increase of population. These changes have been interpreted as a part of the domestication process of their environment that rendered singular archaeological landscapes. Different social, productive and economic hypothesis have been put forward to explain the complex location, distribution and orientation patterns that these architecture displays. Recently, the recurrent and consistent spatial orientation found at the groups of mounds in Uruguay paved the way to new hypothesis that recognize other knowledge related to their ecologic environment, location and distribution. The present study shows the result of an archaeoastronomical investigation on the orientation and location of the mounds in five sites at the Rocha department (Uruguay). We discuss the coherent orientation of these groups of mounds in relation with certain asterisms such as the Southern Cross or the Milky Way and celestial bodies such as the full moon after winter solstice. The results allow discussing how the perception and knowledge of celestial phenomena c. 3000 BP could have played a key role in the organization of space and time among these pre-Hispanic societies. Besides, some results gain particular relevance when contrasted with ethnographic, ethno-historic and archaeological information for other groups in the Southern Hemisphere. This preliminary approach prompt us to conclude that the skylore and the particular perception of time and Nature’s cycles linked with flood and drought periods were part of a holistic technology that allowed these peoples to live in these wet ecosystems.