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The beginning of plant cultivation is one of the most important cultural transitions in human history 1 – 4 . Based on molecular markers showing the genetic similarities between domesticated plants and wild relatives, south-western Amazonia has been proposed as one of the early centres of plant domestication 4 – 6 . However, the nature of the early human occupation and the history of plant cultivation in south-western Amazonia are still little understood. Here, we document the cultivation of Cucurbita at ca. 10,250 cal yr BP, Manihot at ca. 10,350 cal yr BP and Zea mays at ca. 6,850 cal yr BP in the Llanos de Moxos. We show that, starting ca. 10,850 cal yr BP, pre-Columbians created an anthropic landscape made of approximately 4,700 artificial forest islands within a treeless seasonally flooded savannah. Our results confirm the Llanos de Moxos as a hotspot for early plant cultivation and demonstrate that ever since their arrival, humans have caused a profound alteration of Amazonian landscapes, with lasting repercussions for habitat heterogeneity and species conservation.

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The scale, spatial variability and implications of pre-Columbian human-induced changes in the Amazon basin are controversial. While some scholars believe that large settlements and complex societies were limited to areas with favourable environmental conditions and human disturbance was localized, others propose that social complexity developed regardless of environmental constraints and opportunities and that human disturbance was widespread. In order to understand the extent to which environmental preconditions influenced the development of pre-Columbian societies, research is needed that integrates both environmental reconstructions and archaeological data. The present study explores past human–environment interactions in the Llanos de Moxos (LM) in the Bolivian Amazon. Combining extensive fieldwork and remote sensing image analysis, we reconstruct mid- to late-Holocene fluvial activity in the southeastern LM and the formation of a sedimentary lobe left by the Grande River. The lobe deposition created the conditions for the development of fertile, drained soils. We also show how pre-Columbian inhabitants adapted to the sedimentary lobe and managed to maximize the area of land suitable for agriculture by building a drainage/irrigation infrastructure. Our results provide an interpretative framework for the diversity of archaeological remains in the LM and suggest that people reached high levels of social complexity as a result of two necessary factors: favourable environmental conditions and human ingenuity.

We report on previously unknown early archaeological sites in the Bolivian lowlands, demonstrating for the first time early and middle Holocene human presence in western Amazonia. Multidisciplinary research in forest islands situated in seasonally-inundated savannahs has revealed stratified shell middens produced by human foragers as early as 10,000 years ago, making them the oldest archaeological sites in the region. The absence of stone resources and partial burial by recent alluvial sediments has meant that these kinds of deposits have, until now, remained unidentified. We conducted core sampling, archaeological excavations and an interdisciplinary study of the stratigraphy and recovered materials from three shell midden mounds. Based on multiple lines of evidence, including radiocarbon dating, sedimentary proxies (elements, steroids and black carbon), micromorphology and faunal analysis, we demonstrate the anthropogenic origin and antiquity of these sites. In a tropical and geomorphologically active landscape often considered challenging both for early human occupation and for the preservation of hunter-gatherer sites, the newly discovered shell middens provide evidence for early to middle Holocene occupation and illustrate the potential for identifying and interpreting early open-air archaeological sites in western Amazonia. The existence of early hunter-gatherer sites in the Bolivian lowlands sheds new light on the region’s past and offers a new context within which the late Holocene “Earthmovers” of the Llanos de Moxos could have emerged.

The long term response of ancient societies to climate change has been a matter of global debate. Until recently, the lack of integrative studies between archaeological, palaeoecological, and palaeoclimatological data had prevented an evaluation of the relationship between climate change, distinct subsistence strategies, and cultural transformations across the largest rainforest of the world, Amazonia. Here, we review the most relevant cultural changes seen in the archaeological record of six different regions within Greater Amazonia during late pre-Columbian times. We compare the chronology of those cultural transitions with high-resolution regional palaeoclimate proxies, showing that, while some societies faced major reorganisation during periods of climate change, others were unaffected and even flourished. We propose that societies with intensive, specialised land-use systems were vulnerable to transient climate change. In contrast, land-use systems that relied primarily on polyculture agroforestry, resulting in the formation of enriched forests and fertile Amazonian Dark Earths in the long term, were more resilient to climate change.

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