Both freshwater pearly mussels and fish are resources that remain abundant year after year of harvesting. Such subsistence is associated with the earliest pottery in the Americas and may have been the setting that later led to planting of food crops as staples (Oliver, 2008, Piperno and

Pearsall, 1998, Roosevelt, 2014, Roosevelt et al., 1991 and Roosevelt et al., 2012). Although it is sometimes assumed that permanent villages required agriculture (Clement et al., 2010 and Piperno and Pearsall, 1998), there is no evidence for agriculture at the Archaic villages. The offsite pollen sequences from lakes in the general region show distinct patterns of human disturbance from cutting Tofacitinib nmr and burning at the time, but no crop pollen (Piperno, 1995:153; Piperno and Pearsall, 1998:230–232). The sedentary foragers check details of the pottery-Archaic cultures built large shell mounds that cover many hectares up to heights of 5–20 m, creating calcareous soils and attracting calcimorphic vegetation. Away from the main floodplains and coasts, Archaic sites are later, smaller middens that lack pottery

and have more diverse faunal assemblages that include small mammals (Imazio da Silveira, 1994 and Lombardo et al., 2013a). But by ca. 5000 years cal BP, some Amazonian villagers turned to shifting forest horticulture for their calorie supply, relegating fishing, hunting, and collecting to accessory roles (Oliver, 2008:208–210; Pearsall, 1995, Piperno, 1995 and Piperno and Pearsall, 1998:244–265, 280–281). Their cultures have been dubbed Formative (Lathrap, 1970), as presumed precursors to complex societies. Formative sites have been found in many parts of Amazonia, though the cultures, their ages, and character are still poorly known. Many lie buried meters under the surface, making them elusive in site surveys. Some cultures were already complex socially. The Formatives were the first Amazonians to build earthen mounds and make elaborately decorated artifacts

(see Sections ‘Terra Firme mound complex at Faldas de Sangay in the Ecuadorian Oriente’ and ‘Wetland earth mounds of Marajo Island at the mouth of the Amazon’) (Neves, 2012:137–139, 168–171; Roosevelt, 2014:1173–1177; Roosevelt et al., 2012:269–278). They were in constant contact with one another throughout the lowlands and even DNA ligase into the Andes and soon migrated by boat to the Caribbean, taking cultivated tree species with them (Newsom and Wing, 2004 and Pagan-Jimenez and Carlson, 2014). Repeated slash and burn cultivation is considered to have produced the fire-magnetized, lightly charcoal-stained anthropic brown soils called terra mulata, found widely in the Amazon (see Section ‘Anthropic black soils’) ( Arroyo-Kalin, 2012, Lehman et al., 2010 and Rostain, 2013:48). Several such soils have been dated to the Formative (e.g., Neves, 2012:134–151; Roosevelt et al., 2012:275).