Prof Christopher Ramsey

Abstract:

Imprecise chronology has entailed a fuzzy kind of prehistory. Prehistorians should no longer be content with timeframes that employ successive units of 200 years or more duration, or with slow change over the long term as their dominant chronological and interpretative perspective. The means to get away from very generalised accounts of the past is formal chronological modelling in a Bayesian framework. The Bayesian approach in general is outlined, with emphasis on its interpretive and iterative nature. The approach combines calibrated radiocarbon dates with knowledge of the archaeological contexts from which they are derived to produce a series of formal, probabilistic date estimates. Stringent demands are made of both the radiocarbon dates and our archaeological understanding of stratigraphy, associations, sample taphonomy and context in general. The Bayesian process at Alsónyék involved assessment of existing dates, careful definition of aims and objectives, the construction of a rigorous sampling strategy, with an explicit hierarchy of suitable samples, precise understanding of the contexts from which samples are derived, and simulation to achieve cost-effective use of resources. The principal material dated at Alsónyék was human and animal bone. Potential age offsets from non-vegetarian diets are carefully considered; 'perfect pairs' of human and animal bone samples from the same contexts indicate that human bone samples are not subject to wide-scale freshwater reservoir effects. Dietary inputs are estimated formally using a series of Bayesian mixing models. The sequence of iterative sampling submissions between 2012 and 2015 is described, and the procedures of the five laboratories involved are detailed. Procedures for model construction, validation and comparison are discussed. Finally, we consider how we can use precise timings to reveal the web of connections and successions that made up past lives, adding plot and context to a more precise chronicle to create narratives for peopling the past.

Abstract:

We describe here the New Zealand kauri (Agathis australis) Younger Dryas (YD) research project, which aims to undertake Δ14C analysis of ~140 decadal floating wood samples spanning the time interval ~13.1-11.7 kyr cal BP. We report 14C intercomparison measurements being undertaken by the carbon dating laboratories at University of Waikato (Wk), University of California at Irvine (UCI), and University of Oxford (OxA). The Wk, UCI, and OxA laboratories show very good agreement with an interlaboratory comparison of 12 successive decadal kauri samples (average offsets from consensus values of -7 to +4 14C yr). A University of Waikato/University of Heidelberg (HD) intercomparison involving measurement of the YD-age Swiss larch tree Ollon505, shows a HD/Wk offset of ~10-20 14C yr (HD younger), and strong evidence that the positioning of the Ollon505 series is incorrect, with a recommendation that the 14C analyses be removed from the IntCal calibration database. © 2013 by the Arizona Board of Regents on behalf of the University of Arizona.

Abstract:

The excavations at Alsónyék revealed numerous Starčevo features, over 50 in the southern part of subsite 10B and some 500 in subsite 5603. The overwhelming majority of the features uncovered were individual pits and pit complexes. Traces of houses or above-ground structures were recorded, but no certain house plans could be identified; numerous hearths and ovens were found. 25 Starčevo burials have been identified, with some in disused pits and ovens. The occupation excavated in subsite 5603 was substantial, the largest yet discovered in Transdanubia. The north-west distribution of the Early Neolithic cultural complex of the northern Balkans - the Starčevo, Körös and Criş cultures - represents the first food-producing communities in many parts of the Carpathian basin. Starčevo sites are now known in the southern part of western Hungary up to Lake Balaton, but there are many unresolved questions about the precise chronology of the Early Neolithic in Transdanubia and beyond, in the Starčevo-Körös-Criş complex as a whole, and about the character and identity of the first farmers of the region. This paper presents 34 radiocarbon dates from 33 samples, interpreted within a Bayesian framework, for the dating of the Starčevo occupation at Alsónyék. 18 samples of human and animal bone were selected as part of the OTKA-funded project Alsónyék: from the beginnings of food production to the end of the Neolithic in collaboration with the ERC-funded The Times of Their Lives project, in conjunction with 15 existing dates from human burials. The programme aimed to date Starčevo occupation and burials at Alsónyék, and in so doing to contribute to further understanding of the character and pace of the spread of the Neolithic way of life in the region. The Bayesian model presented estimates that Starčevo activity probably began in 5775-5740 cal BC (68% probability), probably lasted for 190-245 years (68% probability), and probably ended in 5560-5525 cal BC (68% probability). The transition from pottery Style group 1 to 2 probably occurred in 5760-5730 cal BC (68% probability), with the transition from pottery Style group 2 to 3 probably in 5595-5570 cal BC (68% probability). The implications of these estimates for the character of the Starčevo occupation at Alsónyék are discussed, as well as for the wider development of the Starčevo culture and of the Early Neolithic in the region as a whole. The current picture suggests the densest Starčevo presence in south-east Transdanubia within the Hungarian distribution of the culture, with a gradual spread to the north later on. The results also demonstrate that Early Neolithic settlements in western Hungary lasted for a substantial period of time, across several human generations.