Substantial biases affecting Combe-Grenal faunal record cast doubts on previous models of Neanderthal subsistence and environmental context

Posted on April 26, 2017 by ARCAS

Publication date: Available online 4 April 2017Source:Journal of Archaeological Science Author(s): Emmanuel Discamps, Jean-Philippe FaivreThis short contribution presents faunal data from new fieldwork at the Middle Palaeolithic site of Combe-Grenal (Dordogne, France). This important sequence continues to serve as both a reference sequence to which other Western European Middle Palaeolithic sites are often compared and the basis of several models of Neanderthal subsistence and environmental context. However, several researchers have highlighted the likelihood that skeletal part profiles were biased as a consequence of the incomplete recovery methods used during previous excavations at Combe-Grenal. A comparison of faunal remains recovered during new excavations with data from the original collections allows recovery bias induced by previous excavation protocols to be quantified. The unreliability of the original skeletal part profiles is confirmed by our study, while, more importantly and unexpectedly, radical biases in species frequencies were equally identified. These results cast doubts on several interpretive models held to account for variability in Mousterian industries, the evolution of Neanderthal hunting strategies, as well as Pleistocene environmental changes. Furthermore, Combe-Grenal provides an instructive example to archaeologists working on sites with less than ideal recovery methods of faunal material. In such cases, recovery biases may be so substantial than even basic faunal data, such as species lists, prove unreliable.

Read more

Use of space and site formation processes in a Neolithic lakeside settlement. Pollen and non-pollen palynomorphs spatial analysis in La Draga (Banyoles, NE Iberia)

Posted on April 14, 2017 by ARCAS

Publication date: May 2017Source:Journal of Archaeological Science, Volume 81 Author(s): J. Revelles, F. Burjachs, N. Morera, J.A. Barceló, A. Berrocal, O. López-Bultó, C. Maicher, M. Le Bailly, R. Piqué, A. Palomo, X. TerradasSeveral taphonomic factors influence the composition of the palynological record especially in archaeological deposits, where human activities alter the representation of taxa. Spatial analysis by a taphonomic approach to the distribution of pollen and non-pollen palynomorphs (NPP) provides useful information about intra-site spaces and environments in the Early Neolithic lakeside settlement of La Draga (Banyoles, NE Iberia). The spatial correlation of algae, lakeshore and aquatic plants and herbs with an economic value, together with eggs of intestinal parasites and spores of coprophilous fungi, evidence a humid and organic environment beneath a hut, where consumption waste is concentrated. In contrast, high values of arboreal pollen (AP) and spores of fungal indicators of soil erosion show a sub-aerial environment strongly altered by taphonomic processes in outside areas. Finally, the association of the highest values in Cerealia-t and the spatial distribution of grinding stones within Sector D identifies an area of cereal processing, proving the suitability of spatial analysis in archaeopalynology as a powerful tool for reconstructing activity areas within archaeological settlements.

Read more

Dents in our confidence: The interaction of damage and material properties in interpreting use-wear on copper-alloy weaponry

Posted on April 13, 2017 by ARCAS

Publication date: May 2017Source:Journal of Archaeological Science, Volume 81 Author(s): Christian Horn, Isabella C.C. von HolsteinThe presence or absence of use-wear marks on copper (Cu)-alloy weaponry has been used since the late 1990s to investigate the balance between functional (combat) and symbolic (value, status, religious) use of these objects, and thus explore their social and economic context. In this paper, we suggest that this work has not taken sufficient account of the material properties of Cu-alloys. We discuss mechanisms of plastic deformation, incremental repairs and corrosion in detail to show how these can obscure use-wear traces. In a survey of Cu-alloy weaponry from the Nordic Bronze Age (1800/1700–550 BCE) from Denmark, Sweden and Germany, we show that corrosion of Cu-alloy objects is strongly linked to depositional context, being greater in burials (both inhumations and cremations) than hoards or as single objects. A relative paucity of use-wear marks on burial weapons should therefore not be used to argue that these were purely symbolic objects, e.g. in contrast to the better preserved hoard material. We propose that use-wear traces on Cu-alloy weaponry, particularly on blade edges, is significantly more elusive than previously realised, and that undamaged objects have been over-identified.

Read more

Reconstructing Ancestral Pueblo food webs in the southwestern United States

Posted on April 10, 2017 by ARCAS

Publication date: Available online 9 April 2017Source:Journal of Archaeological Science Author(s): Stefani A. Crabtree, Lydia J.S. Vaughn, Nathan T. CrabtreeAnalyzing how humans interacted with (and within) their greater ecosystems facilitates a more nuanced understanding of past lifeways. In this aim, we use food web modeling to reconstruct the biotic environment of Ancestral Pueblo people living in the central Mesa Verde region between A.D. 750 and A.D. 1300. This framework enables an investigation into the effects of species introductions and removals by linking humans to the species they consumed. We combine a diachronic examination of multiple archaeological assemblages with a database of every modern non-invasive species and their feeding links in a 4,600 square kilometer area of southwestern Colorado. Although human omnivory provided some flexibility, high population density likely curtailed the ability to prey switch. Ultimately, these factors combined to decrease the resilience of Ancestral Pueblo people to environmental changes.

Read more

Fecal biomarker imprints as indicators of past human land uses: Source distinction and preservation potential in archaeological and natural archives

Posted on April 4, 2017 by ARCAS

Publication date: May 2017Source:Journal of Archaeological Science, Volume 81 Author(s): Renata Zocatelli, Marlène Lavrieux, Typhaine Guillemot, Léo Chassiot, Claude Le Milbeau, Jérémy JacobThis paper presents the potential of 5β-stanols and bile acids to act as fecal source biomarkers in order to identify and characterize past agropastoral activities in archaeological and natural archives. First of all, a molecular inventory of 5β-stanols and bile acids was made on fresh fecal human and domestic animal samples, using the same methodology to define the specificity of these molecular biomarkers. The selected species were cow, horse, pig and sheep as they are the major domestic species present in European archaeological sites. To our knowledge, our work constitutes the first report on fecal biomarkers in sheep feces. Bile acids can distinguish diet regime and species having the same diet with greater specificity than 5β-stanols. Fresh human fecal material and historical/archaeological fecal material were analyzed to assess their stability through time by calculating the coprostanol/epi-coprostanol (Cp/epi-Cp) and deoxycholic acid/cholic acid (DOC/C) ratios. Results show that bile acids are more resistant to diagenesis than 5β-stanols, at least on a 700-year time scale. Human and domestic animal fecal molecular imprints were then compared to the molecular content of 65 samples retrieved from archaeological sites, soils and lacustrine sediments to test their ability to trace past land-use dynamics. This study is the first to combine bile acids and 5β-stanols to identify a source of fecal material in lacustrine sediments. The combination of sterols and bile acids can be used in a variety of natural archives and archaeological contexts to define the origin of fecal material, to specify land-use, and to reconstruct past pastoral practices at various spatio-temporal scales.

Read more