Understanding past population dynamics in lowland South America relative to changes in subsistence is crucial for drawing comparisons with global processes. Here, we use aggregated radiocarbon data as a palaeodemography proxy for in the eastern La Plata Basin and adjacent Atlantic coast, southeastern South America. Our results show that population dynamics in the study area are best explained by a three-phase model consisting of exponential growth ~6000-4000 cal BP, linear decrease ~4000-2000 cal BP and further exponential growth ~2000-500 cal BP. Local deviations from the regional trend show a heterogeneous landscape, with the first phase of exponential growth mainly driven by activity in the coast. Although the first adoption of domesticated plants occurs during that period, a causal relationship with population growth cannot be established, as plant cultivation may have been incorporated into the economy of already large and settled populations approaching carrying capacity. The second phase of exponential growth follows the arrival of new cultural traditions, bringing with them a more diverse package of cultivated plants and landscape management practises. Our results highlight the complexity of the relationships between population dynamics and changes in economy in South America, with a delayed transition attested in our study region.

了解南美洲低地过去与生存变化有关的人口动态对于与全球进程进行比较至关重要。在这里，我们使用汇总的放射性碳数据作为东部拉普拉塔盆地和南美洲东南部相邻大西洋沿岸的古生物学代表。我们的研究结果表明，研究区域内的人口动态可以最好地用一个三阶段模型来解释，该模型由指数增长〜6000-4000 cal BP，线性下降〜4000-2000 cal BP和进一步指数增长〜2000-500 cal BP组成。与区域趋势的局部偏差显示出不同的景观，指数增长的第一阶段主要由沿海地区的活动驱动。尽管在此期间首次采用了驯化植物，但无法建立与种群增长的因果关系，因为植物栽培可能已经纳入已经庞大且定居人口接近承载能力的经济。指数增长的第二阶段是随着新文化传统的到来，随之而来的是更多的栽培植物和景观管理实践。我们的研究结果突出了南美人口动态与经济变化之间关系的复杂性，在我们的研究区域证明了转型的延迟。