PALEODIET: Calibration and application of novel stable isotope (Ca, Sr and Zn) proxies for paleodietary reconstructions

我们吃什么就是什么：饮食可以从人类骨骼和牙齿的稳定同位素组成中推断出来，40年来一直在研究这些组成，以重建过去人口的饮食。利用氮、碳同位素研究人类古食物已取得了很大进展。然而，这些经典的饮食代理，特别是胶原蛋白为基础的氮同位素，是由于成岩偏见往往难以适用于超过50,000年BP。因此，旧石器时代人类的饮食不容易评估。PALEODIET研究项目的目标是：1）校准和联合收割机新的非传统的稳定同位素（锌，钙，锶）代理能够评估目前无法获得的饮食信息，2）应用这个新的同位素工具箱，以提供对尼安德特人饮食的最新见解，使我们能够测试流行的喂养假设。锌，钙和稳定的锶同位素组成的变化可以用来指纹的食物来源，不能确定与目前的饮食代理和量化的消费不同的食物类别。该提案主要关注三个主题：1）描述重要人类食物来源的锌同位素组成，2）评估旧石器时代食物网和尼安德特人饮食中的骨髓和脂肪消耗，3）确定巴西和葡萄牙史前人群的鱼类和贝类开发。通过校准和应用Zn，Ca以及稳定的Sr同位素在现代和上/中旧石器时代动物群和人类遗骸，我们将开发新的饮食代理，有可能被应用到古代化石骨骼遗骸。这将为主要饮食转变（即第一次动物蛋白和贝类消费）与人类谱系的主要进化步骤之间的联系提供新的见解。

We are what we eat: diet can be inferred from stable isotope compositions of bones and teeth of humans which have been studied since 40 years to reconstruct the diets of past populations. Much progress has been made in the field of human paleodiet research using nitrogen and carbon isotopes. However, these classical dietary proxies, especially the collagen-based nitrogen isotopes, are due to diagenetic biases often difficult to apply beyond 50,000 years BP. Paleolithic hominin diets can therefore not be easily assessed. The objectives of the PALEODIET research project are to: 1) calibrate and combine new non-traditional stable isotope (Zn, Ca, Sr) proxies capable of assessing dietary information currently beyond reach, 2) apply this new isotope toolbox to provide uprecedent insights into Neanderthal diets and enable us to test prevailing feeding hypotheses. Variations in Zn, Ca and stable Sr isotopic compositions can be used to fingerprint food sources that cannot be identified with current dietary proxies and quantify the consumption of different food categories. This proposal focuses on three main topics: 1) characterize the zinc isotope compositions of important human food sources, 2) assess bone marrow and fat consumption in Paleolithic food webs and Neanderthal diets, 3) determine fish and shellfish exploitation of protohistoric populations from Brazil and Portugal. By calibrating and applying Zn, Ca as well as stable Sr isotopes on modern and upper/middle Paleolithic faunal and human remains, we will develop new dietary proxies that have the potential to be applied to ancient fossil skeletal remains. This will provide new insights into the link between major dietary transitions (i.e. first animal protein and shellfish consumption) and main evolutionary steps of the human lineage.