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Stable isotopes of mammoths and mastodons have the potential to illuminate ecological changes in late Pleistocene landscapes and megafaunal populations as these species approached extinction. The ecological factors at play in this extinction remain unresolved, but isotopes of bone collagen (δ13C, δ15N) and tooth enamel (δ13C, δ18O, 87Sr/86Sr) from midwestern North America are leveraged to examine ecological and behavioral changes that occurred during the last interglacial-glacial cycle. Both species had significant C3 contributions to their diets and experienced increasing levels of niche overlap as they approached extinction. A subset of mastodons after the last glacial maximum exhibit low δ15N values that may represent expansion into a novel ecological niche, perhaps densely occupied by other herbivores. Stable isotopes from serial and microsampled enamel show increasing seasonality and decreasing temperatures as mammoths transitioned from Marine Isotope Stage (MIS) 5e to glacial conditions (MIS 4, MIS 3, MIS 2). Isotopic variability in enamel suggests mobility patterns and life histories have potentially large impacts on the interpretation of their stable isotope ecology. This study further refines the ecology of midwestern mammoths and mastodons demonstrating increasing seasonality and niche overlap as they responded to landscape changes in the final millennia before extinction.

In 2018 Pearson et al. published a new sequence of annual radiocarbon (14C) data derived from oak (Quercus sp.) trees from Northern Ireland and bristlecone pine (Pinus longaeva) from North America across the period 1700–1500 BC. The study indicated that the more highly resolved shape of an annually based calibration dataset could improve the accuracy of 14C calibration during this period. This finding had implications for the controversial dating of the eruption of Thera in the Eastern Mediterranean. To test for interlaboratory variation and improve the robustness of the annual dataset for calibration purposes, we have generated a replicate sequence from the same Irish oaks at ETH Zürich. These data are compatible with the Irish oak 14C dataset previously produced at the University of Arizona and are used (along with additional data) to examine inter-tree and interlaboratory variation in multiyear annual 14C time-series. The results raise questions about regional 14C offsets at different scales and demonstrate the potential of annually resolved 14C for refining sub decadal and larger scale features for calibration, solar reconstruction, and multiproxy synchronization.

Stable isotopes of mammoths and mastodons have the potential to illuminate ecological changes in late Pleistocene landscapes and megafaunal populations as these species approached extinction. The ecological factors at play in this extinction remain unresolved, but isotopes of bone collagen (δ13C, δ15N) and tooth enamel (δ13C, δ18O, 87Sr/86Sr) from the Midwest, USA are leveraged to examine ecological and behavioral changes that occurred during the last interglacial-glacial cycle. Both species had significant C3 contributions to their diets and experienced increasing levels of niche overlap as they approached extinction. A subset of mastodons after the last glacial maximum (LGM) exhibit low δ15N values that may represent expansion into a novel ecological niche, perhaps densely occupied by other herbivores. Stable isotopes from serial and micro-sampled enamel show increasing seasonality and decreasing temperatures as mammoths transitioned from Marine Isotope Stage (MIS) 5e to glacial conditions (MIS 4, MIS 3, MIS 2). Isotopic variability in enamel suggests mobility patterns and life histories have potentially large impacts on the interpretation of their stable isotope ecology. This study further refines the ecology of midwestern mammoths and mastodons demonstrating increasing seasonality and niche overlap as they responded to landscape changes in the final millennia before extinction.

Lime lumps and bulk mortars show different 14C contamination when analyzed in several CO2 fractions isolated from the effervescence of an ongoing hydrolysis reaction. Age profiles of both materials are therefore highly complementary and together they can provide a reliable date. Furthermore, they can also reveal the complexity of the radiocarbon (14C) distribution within the mortar and thus prevent over-interpretation of the data. The lime lump versus bulk mortar dating data presented here has been collected over 22 years, with only a small fraction of the results so far published internationally. Since there has been an increasing interest in mortar dating over recent years with a special focus on lime lumps, and since many laboratories have just begun mortar dating experiments, we wish to present some of the extensive data that already exist. Previously published data from 15 lime lumps (including 34 14C measurements from sequential dissolution) and 43 new 14C measurements from 17 lime lumps are presented here. The samples are from medieval Finland and Sweden, classical Rome and medieval Italy, and the Roman Jerash (Gerasa), Jordan.

In this study, we review the history of proboscideans in the Great Lakes region (Ontario and western New York) in the context of local glacial and vegetational histories. Further, we investigate mammoth ( Mammuthus ) and mastodon ( Mammut ) environmental niche partitioning using stable isotope analysis of bone and dentin collagen (δ 13 C col , δ 15 N col ) and structural carbonate in tooth enamel bioapatite (δ 13 C sc , δ 18 O sc ), and demonstrate that stable isotopes can be used to identify non-locals among museum specimens with no contextual records. New radiocarbon dates suggest that Ontario mastodons lived in tundra-like environments as well as their more common spruce forest habitat. Local Ontario/New York mammoths and mastodons consumed 100% C 3 -plant diets and drank low- 18 O waters, consistent with colder-than-modern climates and proximity to glacial meltwater sources. Mammoths and mastodons occupied distinct environmental niches, characterized by different oxygen- and nitrogen-isotope compositions and geographical locations. This suggests that direct competition for resources was not a major factor in their local extinction. We suggest that both mammoths and mastodons obtained water from sources formed primarily from precipitation rather than glacial meltwater. We describe how high δ 15 N values in mammoths could have been caused by a combination of preferences for dry environments, consumption of low-nutrient forage (particularly stems and stalks), coprophagy, geophagy, and dung fertilization. We argue that low δ 15 N values in mastodons could have been caused by consumption of trees and shrubs (including nitrogen-fixing taxa) and a preference for recently deglaciated landscapes and/or spruce environments. Finally, we raise the possibility that mastodons contributed to the spruce-pine transition by browsing directly on spruce trees.

Geophysical techniques have been widely employed for the noninvasive location of burial sites in archaeological and forensic investigations. This approach has met with varying degrees of success, depending on factors such as equipment choice, survey methodology, burial type, and geological setting. This paper reports the results of a multitechnique geophysical survey carried out immediately prior to the salvage excavation of two Indigenous burials from an eolian dune in coastal South Australia. Ground-penetrating radar was not successful in defining the location of the burials owing to the disturbed nature of the local stratigraphy. Magnetic field intensity and apparent magnetic susceptibility surveys identified discrete anomalies that coincided with the location of skeletal material revealed during excavation, which we hypothesize to be due to burning or ochre use during funerary practices. Despite the spatial association of these features, subsequent laboratory analyses of the mineralogy and magnetic properties of sediments collected from the site failed to find a definite cause of the anomalies. Nevertheless, the association between them and the primary interment locations has implications for archaeological surveys carried out in the Australian coastal zone, as it highlights the potential of magnetic field intensity and apparent magnetic susceptibility geophysical techniques undertaken with a more refined survey methodology to afford a noninvasive, culturally appropriate means through which to detect Indigenous burials. This approach may prove particularly useful in areas with disturbed stratigraphy where ground-penetrating radar is less effective. © 2010 Wiley Periodicals, Inc.

This paper presents new AMS radiocarbon dating results of six ungulate bones from the current excavation of Isturitz Cave, France, layer C 4c4. The assemblage from this layer exhibits a suite of traits closely aligned with the Early Aurignacian, but with some aspects that bear strong similarities with the Protoaurignacian, with possible in situ technological transformation. Accurate and precise dating of the late Middle Palaeolithic and the early Upper Palaeolithic periods is critical to our understanding of the possible relationship between final Neanderthals and early modern humans in Europe. As such, a rigorous set of sample selection and evaluation protocols was developed and used in this research. Among these, only cutmarked bones were selected and a total of 31 targets were made, giving a weighted average of 37,180 ± 420 BP for this assemblage and providing a terminus ante quem for the ornaments, decorated artefact and amber pendants beneath it. The implications and importance of these results to debates concerning the chronological relationship between the Châtelperronian, Protoaurignacian and Early Aurignacian and associated debates regarding hominin dispersal, interaction and the timing of technical and cultural innovations are discussed.

The impact of cyclododecane on the carbon-14 dating of archaeological materials was investigated using accelerator mass spectrometry. Two conservation-grade and two laboratorygrade cyclododecane samples were determined to be radiocarbon-free, indicating that the chemical is synthesized from petroleum-derived, rather than modern hydrocarbon sources. Radiocarbon dating of modern and archaeological gourd rind samples that were treated with cyclododecane produced the same results as for untreated samples. While the study does not demonstrate that residues are absent from cyclododecane-treated artifacts, it showed that the stringent sample cleaning protocols specifically designed to remove both burial and laboratory contaminants were sufficient to reduce cyclododecane residues to levels that would not interfere with radiocarbon dating.

INTRODUCTION Caves are natural traps and as such are important repositories for both animal and human remains. Hominid remains dating to >4 Ma have been recovered from breccias in South African caves such as Sterkfontein, Swartkrans, and Kromdraai (e.g. Brain, 1981). Uncemented remains of animals are commonly found in the caves of arid lands. For example, bones of a Giant Ground Sloth (Glossotherium harlani), that may have weighed 900 kg, were recovered from a chamber ca. 64 m underground in Grand Canyon Caverns, in western Arizona. The Giant Sloth became extinct between 20 and 11 ka. In the same cave a mummified bobcat was found ca. AD 1950 and was presumed to be about 100 years old at that time (www. desertusa.com). In fact, naturally mummified animals are frequently encountered in arid land caves due to localized dry microclimates that prevent decay. Commonly, the animal falls into the cave or enters via steep or slippery slopes and cannot escape. A difficult entry also denies access to scavenging animals, thus preserving the carcass. In arid areas, animals trapped in caves can Hodgins G., Brook G.A. and Marais E. 2007. Bomb-spike dating of a mummified baboon in Ludwig Cave, Namibia. International Journal of Speleology, 36 (1), 31-38. Bologna (Italy). ISSN 0392-6672.

Preliminary experiments were carried out on archaeological wood to investigate methods of cellulose hydrolysis and carbohydrate monomer purification for the purpose of compound-specific radiocarbon dating. The Chelford log, a known 14C dead source of wood cellulose, was selected for study in order to investigate the levels of contamination introduced during sample purification. Two methods of hydrolysis were examined, mineral acid hydrolysis and enzyme hydrolysis using cellulase from Penicillium funiculosum. Under the conditions described, enzymolysis was far superior to acid hydrolysis in terms of the glucose monomer yield. Glucose monomer purification was accomplished using high pH anion exchange chromatography with pulsed amperometric detection. This high performance liquid chromatography (HPLC) method does not require sample derivatization and the chromatography products can be collected in water. These characteristics make it potentially well suited to carbon dating applications. 14C dating of chromatographically purified glucose fractions revealed significant levels of contamination had accumulated during both protocols. Glucose contamination from the cellulase enzyme preparation was a major source of contamination within the enzymatically hydrolyzed samples. Ultrafiltration of the enzyme removed some but not all of this contamination. The contamination must be reduced 10-fold before the methodology could be viable for dating. This hydrolysis/HPLC method is also being investigated for 14C dating of other carbohydrate polymers such as chitin.

Goats were among the first farm animals domesticated, ≈10,500 years ago, contributing to the rise of the “Neolithic revolution.” Previous genetic studies have revealed that contemporary domestic goats ( Capra hircus ) show far weaker intercontinental population structuring than other livestock species, suggesting that goats have been transported more extensively. However, the timing of these extensive movements in goats remains unknown. To address this question, we analyzed mtDNA sequences from 19 ancient goat bones (7,300–6,900 years old) from one of the earliest Neolithic sites in southwestern Europe. Phylogenetic analysis revealed that two highly divergent goat lineages coexisted in each of the two Early Neolithic layers of this site. This finding indicates that high mtDNA diversity was already present >7,000 years ago in European goats, far from their areas of initial domestication in the Near East. These results argue for substantial gene flow among goat populations dating back to the early neolithisation of Europe and for a dual domestication scenario in the Near East, with two independent but essentially contemporary origins (of both A and C domestic lineages) and several more remote and/or later origins.

The development of radiocarbon dating for degraded bone samples collected at Korean archaeological sites has been successful through the characterization of raw bone C/N ratios and application of an ultrafiltration method. It was found that the C/N ratios of raw bone samples are inversely proportional to the carbon content and residue amount after gelatinization. We have examined a few dozen Korean archaeological bone samples for this study. Well-preserved bone samples are found to be physically dense. The range of C/N ratios of Korean raw bone samples ranged from 3.4 to 74. We found that the C/N ratios of degraded raw bone samples can be used to determine whether 14C samples are acceptable for normal pretreatment processing and eventual dating. The results of this study support that even if the C/N ratio of a degraded raw bone sample is 11, extraction of collagen for bone dating is feasible by a carefully designed ultrafiltration process. Our preliminary 14C dating results of a depth profile of Gunang-gul Cave, an archaeological site in Danyang, Korea, indicate that this site has been either geologically or anthropologically disturbed in the past, with 14C ages ranging from 28,910 ± 200 to 48,090 ± 1050 yr BP. The C/N ratios of the collagen samples of Gunang-gul were determined to be 3.2–3.6. Our study establishes a new guide for the pretreatment of degraded bone samples such as those collected in Korea for 14C dating.

The relationship between temperature and time required for collagenization using modern bone samples was investigated. Gelatinized samples of bone collagen were filtered to selectively collect different molecular weight fractions. The results of this study suggest that heating to 70 ° for a duration of 12 hr provides the optimal conditions for gelatinization.