Bone Collagen Quality Indicators for Palaeodietary and Radiocarbon Measurements

We present a new time-slice reconstruction of the Eurasian ice sheets (British–Irish, Svalbard–Barents–Kara Seas and Scandinavian) documenting the spatial evolution of these interconnected ice sheets every 1000 years from 25 to 10 ka, and at four selected time periods back to 40 ka. The time-slice maps of ice-sheet extent are based on a new Geographical Information System (GIS) database, where we have collected published numerical dates constraining the timing of ice-sheet advance and retreat, and additionally geomorphological and geological evidence contained within the existing literature. We integrate all uncertainty estimates into three ice-margin lines for each time-slice; a most-credible line, derived from our assessment of all available evidence, with bounding maximum and minimum limits allowed by existing data. This approach was motivated by the demands of glaciological, isostatic and climate modelling and to clearly display limitations in knowledge. The timing of advance and retreat were both remarkably spatially variable across the ice-sheet area. According to our compilation the westernmost limit along the British–Irish and Norwegian continental shelf was reached up to 7000 years earlier (at c. 27–26 ka) than the eastern limit on the Russian Plain (at c. 20–19 ka). The Eurasian ice sheet complex as a whole attained its maximum extent (5.5 Mkm2) and volume (~24 m Sea Level Equivalent) at c. 21 ka. Our continental-scale approach highlights instances of conflicting evidence and gaps in the ice-sheet chronology where uncertainties remain large and should be a focus for future research. Largest uncertainties coincide with locations presently below sea level and where contradicting evidence exists. This first version of the database and time-slices (DATED-1) has a census date of 1 January 2013 and both are available to download via the Bjerknes Climate Data Centre and PANGAEA (www.bcdc.no; http://doi.pangaea.de/10.1594/PANGAEA.848117).

The last Eurasian ice sheets - a chronological database and time-slice reconstruction, DATED-1

In this paper, we summarize the main chemical pretreatment protocols currently used for AMS radiocarbon dating at the Oxford Radiocarbon Accelerator Unit, updating the protocols last described by Hedges et al. (1989).

/pdf/current-pretreatment-methods-for-ams-radiocarbon-dating-at-5b6gnjzszc.pdf

Current Pretreatment Methods for AMS Radiocarbon Dating at the Oxford Radiocarbon Accelerator Unit (Orau)

This study illustrates the potential of small-game data for identifying and dating Paleolithic demographic pulses such as those associated with modern human origins and the later evolution of food-producing economies. Archaeofaunal series from Israel and Italy serve as our examples. Three important implications of this study are that (1) early Middle Paleolithic populations were exceptionally small and highly dispersed, (2) the first major population growth pulse in the eastern Mediterranean probably occurred before the end of the Middle Paleolithic, and (3) subsequent demographic pulses in the Upper and Epi-Paleolithic greatly reshaped the conditions of selection that operated on human subsistence ecology, technology, and society. The findings of this study are consistent with the main premise of Flannery's broad-spectrum-revolution hypothesis. However, ranking small prey in terms of work of capture (in the absence of special harvesting tools) proved far more effective in this investigation of human diet breadth than have the taxonomic-diversity analyses published previously.

The Tortoise and the Hare. Small-Game Use, the Broad-Spectrum Revolution, and Paleolithic Demography.

If bone is considered as a composite of collagen (protein) and bioapatite (mineral), then three pathways of diagenesis are identified: (1) chemical deterioration of the organic phase; (2) chemical deterioration of the mineral phase; and (3) (micro) biological attack of the composite. The first of these three pathways is relatively unusual and will only occur in environments that are geochemically stable for bone mineral. However, because rates of biomolecular deterioration in the burial environment are slow, such bones would yield useful biomolecular information. In most environments, bones are not in thermodynamic equilibrium with the soil solution, and undergo chemical deterioration (path 2). Dissolution of the mineral exposes collagen to biodeterioration, and in most cases the initial phase of dissolution will be followed by microbial attack (path 3). Biological attack (3) also proceeds by initial demineralization; therefore paths 2 and 3 are functionally equivalent. However,in a bone that follows path 3 the damage is more localized than in path 2, and regions equivalent to path 1 may therefore exist outside these zones of destruction.

Other biomolecules, such as blood proteins, cellular lipids and DNA, exist within the physiological spaces within bone.For these biomolecules, death history may be particularly important for their survival.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/1475-4754.t01-1-00071

The survival of organic matter in bone: a review

Although the reliability of 14C dates of bone has increased greatly since AMS methods permitted better pretreatment on smaller samples, most old, badly contaminated or severely weathered bone still give serious problems. Several groups have recently proposed improvements to sample purification methods, often supported by a number of 14C measurements. We present here an overview of these improvements. The issue is complicated by the following:
1. Different problems are presented depending on age, preservation and degree of contamination of bone.
2. Methods may or may not be developed with routine application in mind.
3. Determining the conditions for which any method can be regarded as reliable is not at all straightforward.

/pdf/a-review-of-current-approaches-in-the-pretreatment-of-bone-4tal36n4du.pdf

A Review of Current Approaches in the Pretreatment of Bone for Radiocarbon Dating by AMS

Presentation de la 18° liste de datations par radiocarbone concernant la faune du Pleistocene, l'habitat, le mobilier et l'environnement du Paleolithique europeen, oriental et africain, du Mesolithique anglais, du Neolithique et de l'âge des metaux anglais, portugais, africain, et de la prehistoire sud-americaine.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1475-4754.1994.tb00975.x

Radiocarbon dates from the oxford ams system: archaeometry datelist 18

https://www.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1475-4754.1992.tb00507.x

Radiocarbon dates from the oxford ams system: archaeometry datelist 15

Vingt-cinquieme edition de la Datelist d'Archaeometry, regroupant les datations au radiocarbone realisees au laboratoire d'Oxford et concernant des restes humains de Grande-Bretagne, divers materiels archeologiques du Paleolithique et du Mesolithique provenant de Grande-Bretagne, d'Allemagne, de Russie et d'Ukraine et divers materiels archeologiques du Neolithique ou plus tardif, provenant de Grande-Bretagne, d'Irlande et d'Egypte

G. J. Van Klinken

Papers

Bone Collagen Quality Indicators for Palaeodietary and Radiocarbon Measurements

A Review of Current Approaches in the Pretreatment of Bone for Radiocarbon Dating by AMS

Radiocarbon dates from the oxford ams system: archaeometry datelist 18

Radiocarbon dates from the oxford ams system: archaeometry datelist 15

Radiocarbon dates from the oxford ams system: archaeometry datelist 25