Previous dating of the Vi-207 and Vi-208 Neanderthal remains from Vindija Cave (Croatia) led to the suggestion that Neanderthals survived there as recently as 28,000–29,000 B.P. Subsequent dating ...yielded older dates, interpreted as ages of at least ∼32,500 B.P. We have redated these same specimens using an approach based on the extraction of the amino acid hydroxyproline, using preparative high-performance liquid chromatography (Prep-HPLC). This method is more efficient in eliminating modern contamination in the bone collagen. The revised dates are older than 40,000 B.P., suggesting the Vindija Neanderthals did not live more recently than others across Europe, and probably predate the arrival of anatomically modern humans in Eastern Europe. We applied zooarchaeology by mass spectrometry (ZooMS) to find additional hominin remains. We identified one bone that is Neanderthal, based on its mitochondrial DNA, and dated it directly to 46,200 ± 1,500 B.P. We also attempted to date six early Upper Paleolithic bone points from stratigraphic units G₁, Fd/d+G₁ and Fd/d, Fd. One bone artifact gave a date of 29,500 ± 400 B.P., while the remainder yielded no collagen. We additionally dated animal bone samples from units G₁ and G₁–G₃. These dates suggest a co-occurrence of early Upper Paleolithic osseous artifacts, particularly split-based points, alongside the remains of Neanderthals is a result of postdepositional mixing, rather than an association between the two groups, although more work is required to show this definitively.
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Genetic analysis of Paleoamerican human remains suggests that people first entered the Americas sometime between ∼14,000 and ∼16,000 years ago. Evaluation of these data requires unequivocal ...archaeological evidence in a solid geological context that is well dated. Accurately determining the age of late Pleistocene sites is thus crucial in explaining when and how humans colonized the Americas. There are, however, significant challenges to dating reliability, especially when vertebrate fossils (i.e. bones, teeth and ivory) are often the only datable materials preserved at sites.
We re-dated vertebrate fossils associated with the North American butchering sites of Wally's Beach (Canada), La Prele also known as Fetterman (Wyoming), Lindsay (Montana), and Dent (Colorado). Our work illustrates the crucial importance of sample chemical preparation in completely removing contaminants derived from sediments or museum curation. Specifically, our work demonstrates that chromatographic methods, e.g. preparative High Performance Liquid Chromatography and column chromatography using XAD resins, are currently the only efficient methods for removing environmental and museum-derived contaminants. These advanced techniques yield demonstrably more accurate AMS 14C measurements that refine the ages of these four sites and thereby contribute to advancing our understanding of human dispersals across North America during the late Pleistocene.
•The arrival time for humans into North America is still an extremely debated topic.•Butchering sites can reveal the presence of humans even if stone artifacts are absent.•Radiocarbon dates can be inaccurate because of incomplete removal of contaminants.•Chromatographic methods are the most efficient to remove contaminants from bones.•These new dates help to build stronger chronologies for the peopling of the Americas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A skullcap found in the Salkhit Valley in northeast Mongolia is, to our knowledge, the only Pleistocene hominin fossil found in the country. It was initially described as an individual with possible ...archaic affinities, but its ancestry has been debated since the discovery. Here, we determine the age of the Salkhit skull by compound-specific radiocarbon dating of hydroxyproline to 34,950-33,900 Cal. BP (at 95% probability), placing the Salkhit individual in the Early Upper Paleolithic period. We reconstruct the complete mitochondrial genome (mtDNA) of the specimen. It falls within a group of modern human mtDNAs (haplogroup N) that is widespread in Eurasia today. The results now place the specimen into its proper chronometric and biological context and allow us to begin integrating it with other evidence for the human occupation of this region during the Paleolithic, as well as wider Pleistocene sequences across Eurasia.
Red-fleshed fruit occur in a small number of distantly related taxa in different sections of the genus Actinidia (kiwifruit). We describe and identify the anthocyanin profile of fruit of several ...Actinidia species. Differences in the relative amounts of cyanidin- and delphinidin-based anthocyanins determine whether the fruit appear red or purple. Cyanidin derivatives have been found in all Actinidia species that contain anthocyanins, whereas delphinidin derivatives are limited to two taxa: A. melanandra and A. arguta var. purpurea. The fruit of these not only contain a wider range of anthocyanins, but they also have greater concentrations. Anthocyanins of most Actinidia species are usually conjugated with either xylosyl-galactose or galactose, whereas A. deliciosa anthocyanins are conjugated with glucose and galactose.
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Denisova Cave, a Pleistocene site in the Altai Mountains of Russian Siberia, has yielded significant fossil and lithic evidence for the Pleistocene in Northern Asia. Abundant animal and human bones ...have been discovered at the site, however, these tend to be highly fragmented, necessitating new approaches to identifying important hominin and faunal fossils. Here we report the results for 8253 bone fragments using ZooMS. Through the integration of this new ZooMS-based data with the previously published macroscopically-identified fauna we aim to create a holistic picture of the zooarchaeological record of the site. We identify trends associated with climate variability throughout the Middle and Upper Pleistocene as well as patterns explaining the process of bone fragmentation. Where morphological analysis of bones from the site have identified a high proportion of carnivore bones (30.2%), we find that these account for only 7.6% of the ZooMS assemblage, with large mammals between 3 and 5 more abundant overall. Our analysis suggests a cyclical pattern in fragmentation of bones which sees initial fragmentation by hominins using percussive tools and secondary carnivore action, such as gnawing and digestion, likely furthering the initial human-induced fragmentation.
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Four ellagitannins from boysenberry, a cross between
Rubus loganbaccus and
Rubus baileyanus Britt., were isolated by preparative HPLC and the exact structures determined by a combination of ...LC–ESI-MS/MS, MALDI-TOF-MS and NMR spectroscopy. The two most abundant ellagitannins were identified as sanguiin H-6, which is known to be abundant in
Rubus species, and the other was identified as an isomer of sanguiin H-10, which has not previously been reported in
Rubus. The two less abundant ellagitannins were identified as sanguiin H-2 and galloyl–bis-HHDP–glucose
2-gallate. Sanguiin H-2 has been previously reported in
Rubus, whereas both sanguiin H-2 and galloyl–bis-HHDP–glucose
2-gallate have been previously reported as hot-water degradation products of lambertianin C. Even though lambertianin C is reported to be a major ellagitannin in other
Rubus species, it was not found in any of the fractions, suggesting that both sanguiin H-2 and galloyl–bis-HHDP–glucose
2-gallate are present naturally in boysenberry.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The sonoelectrochemical degradation of phenol in aqueous solutions with stainless steel electrodes and high-frequency ultrasound (850kHz) was investigated. A 60% synergetic effect was obtained in the ...combined reaction system. High concentration of electrolyte (sodium sulfate) and a high electrical voltage are favorable conditions for the degradation of phenol. A nearly complete degradation of phenol was achieved with 4.26g/L Na2SO4 and 30V electrical voltages at 25°C in 1h. The degradation of phenol follows pseudo-first order kinetics. Considering costs and application, the energy efficiency of the reaction system with different reaction conditions was evaluated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Understanding extinction events requires an unbiased record of the chronology and ecology of victims and survivors. The rhinoceros Elasmotherium sibiricum, known as the 'Siberian unicorn', was ...believed to have gone extinct around 200,000 years ago-well before the late Quaternary megafaunal extinction event. However, no absolute dating, genetic analysis or quantitative ecological assessment of this species has been undertaken. Here, we show, by accelerator mass spectrometry radiocarbon dating of 23 individuals, including cross-validation by compound-specific analysis, that E. sibiricum survived in Eastern Europe and Central Asia until at least 39,000 years ago, corroborating a wave of megafaunal turnover before the Last Glacial Maximum in Eurasia, in addition to the better-known late-glacial event. Stable isotope data indicate a dry steppe niche for E. sibiricum and, together with morphology, a highly specialized diet that probably contributed to its extinction. We further demonstrate, with DNA sequencing data, a very deep phylogenetic split between the subfamilies Elasmotheriinae and Rhinocerotinae that includes all the living rhinoceroses, settling a debate based on fossil evidence and confirming that the two lineages had diverged by the Eocene. As the last surviving member of the Elasmotheriinae, the demise of the 'Siberian unicorn' marked the extinction of this subfamily.
The anthocyanins responsible for the red color of red kiwifruit were extracted in acidified ethanol and isolated by solid phase extraction (SPE) followed by preparative HPLC. Five anthocyanins were ...obtained and subsequently identified as delphinidin 3-2-(xylosyl)galactoside, delphinidin 3-galactoside, cyanidin 3-2-(xylosyl)galactoside, cyanidin 3-galactoside, and cyanidin 3-glucoside by a combination of LC-MS/MS, GC-MS, and 2D NMR. Delphinidin 3-2-(xylosyl)galactoside and delphinidin 3-galactoside have not previously been reported in the genus Actinidia.
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Rationale
For radiocarbon results to be accurate, samples must be free of contaminating carbon. Sample pre‐treatment using a high‐performance liquid chromatography (HPLC) approach has been developed ...at the Oxford Radiocarbon Accelerator Unit (ORAU) as an alternative to conventional methods for dating heavily contaminated bones. This approach isolates hydroxyproline from bone collagen, enabling a purified bone‐specific fraction to then be radiocarbon dated by accelerator mass spectrometry (AMS).
Methods
Using semi‐preparative chromatography and non‐carbon‐based eluents, this technique enables the separation of underivatised amino acids liberated by hydrolysis of extracted bone collagen. A particular focus has been the isolation of hydroxyproline for single‐compound AMS dating since this amino acid is one of the main contributors to the total amount of carbon in mammalian collagen. Our previous approach, involving a carbon‐free aqueous mobile phase, required a two‐step separation using two different chromatographic columns.
Results
This paper reports significant improvements that have been recently made to the method to enable faster semi‐preparative separation of hydroxyproline from bone collagen, making the method more suitable for routine radiocarbon dating of contaminated and/or poorly preserved bone samples by AMS. All steps of the procedure, from the collagen extraction to the correction of the AMS data, are described.
Conclusions
The modifications to the hardware and to the method itself have reduced significantly the time required for the preparation of each sample. This makes it easier for other radiocarbon facilities to implement and use this approach as a routine method for preparing contaminated bone samples.
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