Understanding formation processes is crucial for interpreting sites with complex sedimentary histories and exceptional archaeological records, such as Level 3 of Des-Cubierta Cave. This Middle Paleolithic unit contains an assemblage of anthropically modified ungulate horned crania, Mousterian lithics, and evidence of fire use, all preserved in a clast-supported gravel deposit shaped by successive rockfalls. This study integrates geostatistical analyses with traditional spatial and taphonomic methods to examine the cone-shaped sedimentary structure that dominates the level and its influence on the spatial distribution and preservation of archaeological materials. The results reveal distinct spatial patterns for geological and archaeological materials, indicating separate formation dynamics. Size-based spatial analyses of boulders characterize the morphology of the conical structure, highlighting size sorting and intensity variations that may indicate sedimentary hiatuses. Bone refitting analysis suggests limited post-depositional movement, with material distribution shaped by the conical sedimentary structure and karst gallery morphology. Variability in crania preservation correlates with proximity to the cone’s apex and elevation, with better-preserved specimens in central areas and more fragmented remains in zones affected by erosive and edaphic processes. These findings underscore the value of integrating geostatistical and traditional archaeological approaches to advance interpretations of spatial and temporal patterns in karst environments and provide a methodological approach for examining sites with similar sedimentary histories. Moreover, the results support the interpretation of a recurrent, culturally motivated Neanderthal behaviour centred on the deliberate accumulation of large ungulate crania, pointing to a symbolic dimension in these practices.
Proteins are highly susceptible to degradation at high temperatures, and it is thus generally assumed that ancient proteins do not preserve in burned materials. So far, research has mainly focused on structural, mechanical, and chemical changes in bone upon heating, while investigations into the degradation and recovery of bone protein from heated bones are more limited. In this study, we experimentally heated pig ribs up to 750°C. To also assess the impact of subsequent resin impregnation on protein recovery, samples were impregnated with resin following heating. We used Fourier Transform Infrared Spectroscopy (FTIR) to assess structural and chemical changes to the bone. Zooarchaeology by Mass Spectrometry (ZooMS) utilising MALDI-ToF-MS was then applied to examine until what temperature heated bones can successfully be identified using a peptide marker-based approach. Our results show that bones heated up to ~ 200°C can be successfully identified with ZooMS. Resin-impregnation leads to a decrease in the number of recovered peptide marker peaks, at times impacting successful taxonomic identification. These findings provide new insights into the effects of heating and resin impregnation on protein preservation and highlight the potential and limitations of palaeoproteomic approaches for the analysis of burned bones from archaeological contexts.
ABSTRACT Paleoenvironmental records indicate that Neotropical regions near the Equator experienced reduced rainfall during the Last Glacial Maximum (LGM). However, some records show conflicting environmental signals. To address these discrepancies, previous studies have proposed two demographic/genetic scenarios for cloud forests based on contrasting precipitation regimes. Here, we apply a multiproxy approach to extinct proboscideans, commonly referred to as gomphotheres, from Ecuador to assess the extent to which wet‐ and dry‐forest models shaped environmental conditions on the coast and in the Inter‐Andean Valley during the Late Pleistocene. Fossil molars were analyzed using stable isotope analysis, dental microwear analysis, and radiocarbon dating. Radiocarbon dates obtained from the sampled gomphotheres span ca. 31,820–23,830 cal yr. BP. Enamel bioapatite δ13C values, ranging from −14.82‰ to −0.78‰, indicate that these proboscideans occupied a broad range of environments, although the overall isotopic signal points to a predominance of more open and relatively dry habitats. Dental microwear data support this interpretation, indicating substantial grass consumption. Reconstructed meteoric water δ18O values derived from enamel bioapatite reveal a clear altitudinal effect on gomphothere distribution. Moreover, these values are comparable to those recorded at present‐day meteorological stations in Ecuador. We therefore infer that, at least during the lifetimes of the sampled individuals, there were no major differences in the δ18O signature of atmospheric circulation between the Late Pleistocene and today in this region. Although substantial chronological gaps remain in paleoenvironmental reconstructions, our results suggest that processes consistent with the Dry Refuge Model (DRM) had a strong influence on Ecuadorian landscapes during the Late Pleistocene. In this scenario, cloud forests were displaced and compressed into refugia due to the combined effects of aridity and cooling.
This article presents the first systematic assessment of ethical concerns specific to archaeobotanical research, focusing on principles and values. Conducted by an international group of archaeobotanists, the study used an anonymous online survey to document experiences and perceptions within the archaeobotanical community with the aim of raising awareness, identifying prevalent good practices and noting points for improvement. The questionnaire included ten thematic blocks and 63 main questions that covered regulations and guidelines, archaeobotany in excavations, funding, credit and authorship, intellectual property and right to access material, engagement with local communities, research obstacles, misconduct, ecological footprint, and dissemination of research results. We received responses from 114 participants, and the results highlight key challenges, including limited systematic recovery and study of plant remains, scarce funding, unclear decision-making authority, recurrent research misconduct, insufficient benefits for local communities, and low visibility of archaeobotanical research in dissemination and outreach. Building on these findings, we propose a declaration of principles tailored to archaeobotany, outlining the collective commitments of our community. This framework emphasizes safeguarding archaeological plant remains, ethical and rigorous research practices, and equitable participation. By adhering to these principles, archaeobotanists can promote scientific knowledge whilst fostering inclusivity, transparency, and respect for all individuals and communities involved or affected by our research. In this way, the initiative aims to strengthen archaeobotany as a discipline and cultivate a more ethical, inclusive, and collaborative research culture for both current and future generations of archaeobotanists.
