Who were the Neanderthals and what caused their demise? To answer these questions, the classic approach in archaeology relies on the analysis of the Neanderthals' stone-tool assemblages and the mineralized bone remains of their dietary intake. Although this approach has yielded a great deal of important information about the Neanderthals’ fate, it is also limited in the sense that the only evidence that is considered is in-organic in nature. The PALEOCHAR Project attempts to answer these questions by considering microscopic and molecular evidence that is organic in nature. By studying the organic sedimentary record at such fine scales, we are able to extract information about, for example, the fat contents of the Neanderthal food, the way they made fire, the arrangements of their living spaces, their surrounding vegetation and the climatic conditions where they lived. By combining these different sources of information we aimed to provide a more complete picture of the Neanderthals and the reason of their disappearance.
Specifically, the PALEOCHAR project examines how Neanderthal diet, fire technology, settlement patterns, and surrounding vegetation were affected by changing climatic conditions. To do so, the project integrates methodologies from micromorphology and organic geochemistry. A key and innovative aspect of the proposal is the consideration of microscopic and molecular evidence that is both organic and charred in nature. Climatic changes and behavioural responses were examined at two Iberian sites which represent two key points along the Neanderthal timeline, finding significant climatic fluctuation and revealing a diversity of adaptations in fire technology.
The results of this project made important contributions to the development of new methods for archaeological research, trained a new generation of skilled geoarchaeologists knowledgeable in microstratigraphy and applied chemistry, and yielded new insights into the Neanderthals and their demise. Regarding the Neanderthals, we achieved a millennial-scale paleoclimatic reconstruction of the regional conditions at El Salt and Abric del Pastor sites that bring us closer to understanding the palaeoenvironmental context for the disappearance of Neanderthals in Eastern Iberia. We also discovered and characterized previously undocumented pit-fire Neanderthal technology and investigated Neanderthal settlement patterns at very narrow time frames. On the methodological side, we developed a method to carry out in-situ, high-resolution identification of archaeological lipid biomarkers on resin-impregnated sediment slabs, and a method to characterize charred organic matter in micromorphological thin sections by means of Raman spectroscopy. We discovered anatomical part differences in plant wax lipids and their different transformations at different burning temperatures, identified animal fat pyromarkers (lipid compounds that form during burning) and their isotopic signatures for the distinction between different species, characterized the effects of burning in the lipid content of animal dung, moss and Hydrogen isotope ratios in alkanes, and established a QuEChERS-based method combined with gas chromatography-mass spectrometry for the analysis of alkanes in sediments.
At present, the AMBILAB (Archaeological Micromorphology and Biomarkers Research Lab) has a prestigious reputation within the international scientific community as an important international hub for training and research in microcontextual geoarchaeology focusing on the organic record.
