Southern Jê mobility landscape of the Ribeira de Iguape Valley [Paisagem de mobilidade Jê Meridional do Alto Vale do Ribeira de Iguape]

Abstract

In this paper, we discuss the Southern Jê occupation of the Ribeira de Iguape Valley in Adrianópolis (Paraná, Brazil), located between the states of Paraná and São Paulo, one of the few valleys in southern Brazil that connects the sea to the hinterland and which was occupied by many different cultures such as hunter-gatherers, shellmound builders, Jê and Tupiguarani ceramics producing groups. These characteristics of long periods of occupation by different groups of people and geographical location provide the possibility of studying human mobility and its relation to the landscape. The analysis of lithics and ceramics found in two sites (Margem I and Margem II) dated between 1304 cal CE (Common Era) and 1440 cal CE, has raised specific questions about the mobility of Jê groups in the Ribeira de Iguape Valley. It was inferred that the Margem II site could have been used as a residential area, due to the large amount of ceramic fragments (more than 5000) and lithic artifacts. Meanwhile, the Margem I site was interpreted as an area of specific tasks such as the production of ceramic vessels due to the discovery of more than twenty fire pits and several clay nodules. The analysis of the lithic artifacts identified a preferential choice of the raw material for tool production and was able to identify the transport of the raw material along the valley, especially from the lower portion of the river where a source of chert is known. It was also possible to verify conservation strategies such as maintenance and recycling of tools. These analytical results suggested that the site area was a convergence point in the landscape and therefore could help to understand the mobility of Southern Jê groups. To test this hypothesis, we applied a spatial model of mobility using Geographic Information Systems (GIS) to calculate routes and the energetic cost of movement in the landscape using hydrological tools. In the archaeological literature this type of model is commonly used to assess the mobility of groups in relation to monumental sites such as mounds and enclosure complexes, but it can be used in relation to a residential site as well. The final model resulted in the definition of a series of routes and six different mobility areas, these areas were defined using GIS watershed tools, but refer not to water drainage but rather to movement within the landscape. Within the model, we can visualise which are the most likely routes to take when going to the Margem II site from different portions of the valley. Using the hydrology tools to define routes made it also possible to classify the routes in a hierarchy and by doing so we were able to define five main routes that concentrate the greatest amount of movement in direction to the Margem II site. One of the nodal points that connects two of these main routes coincided with the exact location of an important proto-Jê funerary site, indicating that the site location might be related to its position within the movement network of the valley. This study has demonstrated the viability and advantages of employing spatial modelling in the interpretation of the archaeological landscape, highlighting the mutual relations between the physiographic, social, political, and symbolical aspects that together make up the landscape.