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Bone collagen is an important material for radiocarbon, paleodietary, and paleoproteomic analyses, but it degrades over time, making such analyses more difficult with older material. Collagen preservation between and within archaeological sites is also variable, so that much time, effort, and money can go into the preparation and initial analysis of samples that will not yield meaningful results. To avoid this, various methods are employed to prescreen bone for collagen preservation (e.g., %N, microporosity, and FTIR spectroscopic analyses), but these are often destructive and/or require exportation for analysis. Here, we explore near-infrared spectroscopy as a tool for gauging the collagen content of ground and whole bone from about 500 to 45,000 years ago. We show that a portable spectrometer’s ability to quantify collagen content and classify specimens by preservation status is comparable to that of other popular prescreening methods. Moreover, near-infrared spectroscopy is non-destructive and spectra can be acquired in a few seconds.

International audience; The ritual human burials and scattered fragments of human bones excavated from Dolni Vestonice II and Pavlov I (Czech Republic) in the 20th century provide a large body of evidence on morphology and funerary practices in the Gravettian as well as the population history of European Homo sapiens during the Upper Palaeolithic. A series of radiocarbon dates on charcoal and animal bone places the occupation of the sites predominantly between 31,000-29,000 cal BP (Early-Evolved Pavlovian) but direct radiocarbon dating of the human remains has not been previously undertaken. In 2013, human bones from Dolni Vestonice II and Pavlov I were sampled for aDNA analysis, including three skeletons from a triple burial (DV13, DV14, DV15), two skeletons from single burials (Pav1, DV16) and two unarticulated human bones (DV42, DV43). Small amounts of bone material were left over from the aDNA sampling, providing the first opportunity to directly date seven of the human individuals. Non-destructive pre-screening with near-infrared (NIR) spectroscopy indicated that sufficient collagen was preserved in the bone material for radiocarbon dating. We sampled very small amounts (32-202 mg) of bone material for collagen extraction, ultrafiltration and accelerator mass spectrometer (AMS) dating. Each collagen extract was dated multiple times using both graphite targets (ca. 800 mu g C) and the gas ion source (< 100 mu g C) of the AixMICADAS to obtain accurate and precise radiocarbon ages. The direct dates confirm the Pavlovian origin of the human remains and indicate that several of the radiocarbon dates carried out in the 1980s on associated charcoals were likely affected by low-level contamination of modern carbon. The results add seven individuals to the small collection of reliably dated Upper Palaeolithic humans in Europe.