JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.Recent archaeological investigations along the louver Negro and upper Xingu Rivers in the Brazilian Amazon provide important new evidence bearing on long-standing debates about the size and permanence of Amerindian settlements in the region. Preliminary regional surveys and more in-depth study of selected large (30-50 ha) sites, particularly analyses of the associations betuveen structuralfeatures, anthropogenically altered soils, and artifact distributions, lead us to conclude that large, permanentsettlements, likely associated withfairly dense r egionalpopulations, existed prehistorically in both areas. Thesefindings cast doubt on the view that environmental limitations prevented sedentism and demographic growth among Amerindian populations througSlout much or all of the region. Specifically, we conclude that fully sedentary and relatively large populations emerged in a variety of Amazonian settings prehistorically, not necessarily cor)elated uvith the distribution of one or another narrowly defined ecological variable (e.g., 11igh fertility soils). Thus, a critical evaluation of core concepts in Amazonian anthropology, such as the varzealterra f rme dichotomy or tropicalforest culture, is advised. lnvestigaciones arqueologicas )ecientes a lo largo de los rfos bajo Negro y alto Xingu, en la Amazonia brasilena, proporcionan nuevas e importantes evidencias para los prolongados debates acerca del tamano y la permanencia de los asentamientos amerindios en la region. Relevamientos preliminares realizados en la region y estudios mas profundos de sitios de 30 a 50 hectareas, particularmente un analisis de la asociacion entre rasgos estructurales, suelos antropoge'nicamente alterados y distribuciones de artefatos, nos llevan a concluir que estos asentamientos de gran tamano y permanentes, probablemente asociados a poblaciones regionales bastante densas, existieron prehistoricamente en ambcxs areas. estos hallazgos plantean serias dudas a la vision, sostenida por mucho tiempo, de que limitaciones medioambientales habrfan impedido el sedentarismo y el crecimiento demografico entre las poblaciones amerindias de la region. ConcluAmos, especificamente, que poblaciones plenamente sedentarias y relativamente amplias emergieron prehistoricamente en una variedad de escenarios amazonicos, no necesariamente correlacionadas con la distribucion de ninguna variable ecologica estrechamente definida. Por consiguiente, se requiere una evaluacion crftica de ciertos conceptos in corporados en la an tropolog fa amazona tales como la dicotom fa valleltierra firme o la cu ltura de la floresta tropical.A merindian settlement patterns in Amazonia have been a source of considerable debate, particularly focusing ...