Based on dental morphology, it was recently suggested that the Southeast Coast of Brazil was inhabited by different biological groups throughout the Holocene. Among those that inhabited São Paulo state, coastal shellmound builders seem biologically distant from riverine shellmound builders. Additionally, individuals that later built ichthyological sites are also biologically distant from both early coastal or riverine populations. However, mainly due to low sample sizes, such conclusions may not be reliable, and require further inquiry. Here, we explore the confidence interval of biological affinities among five archaeological series (Piaçaguera, Buracão, Tenório, Mar Virado and Moraes), composed by 128 individuals from different chronological and archaeological backgrounds. We use a bootstrapping analysis of biodistances, which illustrates the expected error that results from sample sizes, by generating density estimations based on the observed biological affinities among series. Our results contradict previous claims based on dental analyses by showing that individuals from ichthyological sites cannot actually be considered distinct from Southeast coastal and riverine shellmound builders. On the other hand, it shows that early coastal and riverine shellmound builders are not biologically related, thus supporting prior assumptions of high phenotypic variation among Southeast shellmound builders, at least within the scope of São Paulo state. Finally, although shellmound builders are related to individuals from ichthyological sites to some extent, early and later coastal shellmound builders of this area do not appear to be biologically related, which further highlights the complex dynamics of population movement in the area.

根据牙齿形态，最近有人提出巴西东南海岸在整个全新世居住着不同的生物群。在居住在圣保罗州的那些人中，沿海贝丘建造者似乎在生物学上与河流贝丘建造者相距甚远。此外，后来建造鱼类学遗址的个体在生物学上也远离早期沿海或河流种群。然而，主要由于样本量小，这样的结论可能并不可靠，需要进一步调查。在这里，我们探讨了五个考古系列（Piaçaguera、Buracão、Tenório、Mar Virado 和 Moraes）之间生物亲缘关系的置信区间，这些系列由来自不同年代和考古背景的 128 个人组成。我们使用生物距离的自举分析，它通过基于观察到的系列之间的生物亲和力生成密度估计来说明由样本大小导致的预期误差。我们的结果与先前基于牙科分析的主张相矛盾，因为它表明来自鱼类遗址的个体实际上不能被视为与东南沿海和河流贝丘建造者不同。另一方面，它表明早期的沿海和河流贝丘建造者在生物学上没有相关性，因此支持了东南贝丘建造者之间高表型变异的先前假设，至少在圣保罗州范围内。最后，虽然贝丘建造者在某种程度上与鱼类遗址的个体有关，但该地区早期和后期的沿海贝丘建造者似乎没有生物学相关性，