GUAYAS BASIN

The Guayas Basin has long been a significant locus of intensive agricultural production and the remnants of raised fields and drainage canals offer visible evidence of preHispanic landscape management on a broad scale. When first observed from the air these were compared with other extensive raised field systems in the tropical lowlands that are subject to annual inundation, ranging from the San Jorge Basin in Colombia to the Llanos de Mojos in eastern Bolivia (see discussion of raised fields in Chapters 11, 12, 13, 16 and 46 in this volume) and even including the high altitude Titicaca Basin complexes in Peru and Bolivia (e. g., Carney et al. 1993; Erickson 1993; Janusek and Kolata 2004; Parsons 1969). Although many of the Guayas Basin field systems have been obliterated in recent decades by modern agricultural production, some nine main surviving concentrations of raised fields covering roughly 500 sq km have been identified (Denevan 1985).

On the Rio Daule the initial construction of raised field systems is thought to have been underway by the late first millennium B. C. and to have been progressively elaborated in the course of the long Yumes phase (AD 400-1600) (Stemper 1993). Stemper infers that the mobilization of the labor force required to maintain the continuously expanding cycle of agricultural infrastructure and production would have reinforced local chiefly authority and power and that this finds material expression in the appearance of a two-tiered settlement pattern with the construction of the first earthen platform mounds (tolas) beginning around AD 400-600 (Stemper 1993:168). Research in the upper Guayas Basin (Guillaume-Gentil 1988, Guillaume-Gentil et al. 1999), at Samborondon (Denevan and Mathewson 1983) and at Penon del Rio at the mouth of the Babahoyo River (Marcos 1987, Dominguez 1990) and in the adjacent Milagro-Yaguachi-Taura area (Delgado-Espinoza 1992) demonstrates further evolution in the settlement hierarchy among Milagro-Quevedo polities from AD 800-1500. The Milagro-Yaguachi-Taura raised field complexes are associated with a three-tier site hierarchy in which domestic households are located in or immediately adjacent to raised fields while the local elite are based at the larger, higher order sites (Delgado-Espinoza 2005). Some of these are organized around single tolas while others have groups of tolas forming conspicuous landmarks visible from afar in the riverine flatlands. From these centers local lords oversaw deployment of the labor force, managed production and controlled access to exotic materials such as spondylus beads, metalwork, obsidian and textiles (Delgado-Espinoza 2006). Delgado (2002) surmises that there was a progressive expansion of the raised field systems and their accompanying settlements from the upper and middle basin towards the mouth of the Guayas drainage where most of the mound construction took place during the

Late period (Acuna 1996; Stemper 1988). This is marked by stacked urn burials in tolas and a distinctive widespread pottery style whose notable feature is the use of applique zoomorphic designs to embellish ceremonial vessels (Estrada 1957; Zevallos 1995).

The Penon del Rio site is ideally positioned to regulate the flow of resources coming into the Gulf of Guayaquil from further afield. The late Milagro-Quevedo occupation at Penon del Rio features the construction of mounds around open public spaces (Dominguez 1990). Faunal remains recovered from the main mounds and adjacent plazas indicate consumption of domesticated duck (cairina moschata), delicacies such as guinea pig (cavia porcellus) and llama (lama) as well as coca (Stahl 2005; Stahl, Muse and Delgado 2006).

Muse (1981, 1991) proposes that the site functioned as a kind of entrepot to which products were brought to be stored and exchanged and that the power of local lords derived from their capacity to organize and regulate this exchange via regional trading contacts and alliances. Local elites at this and other nearby sites had access to imported copper alloy objects including “money-axes” while some hammered sheet metal objects also seem to have been produced locally (Sutliff 1989). Balsa wood (ochoroma sp.) is native to the coastal lowlands and the riverine societies of the lower Guayas basin used balsa and cane rafts as well as canoes to trade upriver, linking with terrestrial routes that facilitated exchange between highlands and lowlands (Zevallos 1995). Thus, local lords seem to have been instrumental in extracting and utilizing the surplus from agricultural production in order to participate in exchange networks to obtain a range of sumptuary goods including marine shells and obsidian flakes to be worked by specialized artisans (Suarez 1991; see also Lopez 2005).