The Times of Their Lives : High-resolution Radiocarbon-based Chronological Analysis of the European Neolithic, through Formal Modelling

The Times of Their Lives, funded by the European Research Council and jointly led by Alasdair Whittle and Professor Alexandra Bayliss, Head of Scientific Dating, Historic England, is an ambitious attempt to take the pre- out of prehistory, and to write narratives about the people of the past, routinely down to the scale of lifetimes and generations.

Up till now, for most regions and for most sequences around the world, prehistorians have only been able to assign the past people whom they study to rather imprecise times. Such imperfect chronology comes from our reliance on radiocarbon dating and a conventional approach to the interpretation of radiocarbon results, which relies on the visual inspection of calibrated dates. Typically, a radiocarbon sample from a few thousand years ago will calibrate to a date spanning 100–200 years (at two standard deviations). A group of such samples will not produce identical calibrated dates, even when they derive from the same event, and archaeologists visually inspecting a graph of such dates (in common parlance in English, ‘eyeballing’) tend to infer that things began earlier, lasted for longer, and ended later than was the case in reality; they also accept the relative imprecision of the dating. In the European Neolithic there has been a long-standing tradition of inferring chronology by ‘summing’, first uncalibrated, and then later on calibrated, radiocarbon dates. This method similarly tends to produce inaccurate chronologies of exaggerated duration. For the fortunate few, in regions with favourable conditions in which wooden timbers are preserved, dendrochronology can provide dates precise to a calendar year and even to a season within a given year, for example among the Pueblo settlements of the American Southwest or the Neolithic and Bronze Age settlements on the fringes of the Alps in western and central Europe. In most regions, however, such preservation and such chronologies are exceptional.


Although there are fine and long-established traditions of chrono-typology and seriation of the abundant material record in the European Neolithic, which can suggest finer chronological resolution, researchers of this period and prehistorians in general seem content with radiocarbon-backed culture history chronologies which employ successive units of 200 years’ or more duration; the innumerable chronological tables familiar from papers and books chart these units over and over again.

Unsurprisingly, as a result, slow change over the long term has been the dominant chronological perspective. Many prehistorians have been content to write accounts of the past which have been very generalised; they regularly lump together in broadly defined phases, often of several centuries or more, events, constructions and other phenomena which might well not be coeval, and many like to emphasise the long-term development of change, in a search for long-running or underlying processes, at the expense of shorter-term events and successions.

The Times of Their Lives and other formal chronological modelling projects challenge these default perspectives. The application of Bayesian statistics for the interpretation of radiocarbon dates allows chronologies that are precise within a scale of human lifetimes and generations to be constructed routinely. The Bayesian approach involves analysing new evidence about a problem in the context of our existing experience and knowledge about that problem. This lets us gain a new understanding of the problem which incorporates both our previously existing knowledge and our new data. This is done by the use of formal probability theory, where all three elements of our model are expressed as probability density functions. These give a quantitative measure of our state of knowledge of each component of the model. Bayesian models are interpretative constructions that rely on multiple lines of evidence. Bayesian statistics, being a formal methodology, force archaeologists to be explicit about their strands of reasoning.

The approach thus 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 routinely involves critical assessment of existing dates, careful definition of aims and objectives, the construction of a rigorous sampling strategy, with an explicit hierarchy of suitable samples (to ensure that samples selected are the same age as the contexts which they are used to date), precise understanding of the contexts from which samples are derived, and simulation to achieve costeffective use of resources. The process is iterative and interpretive.  The outcome can be much more precise estimates of timing, and from those can come a higher-resolution grasp of duration and the tempo of change. This opens up a whole range of new interpretive possibilities and challenges, getting us closer to the agency of people in the past, but also raising the question of how we are to write narratives which combine a spectrum of timescales.


The Times of Their Lives was preceded by other projects. Alexandra Bayliss and Alasdair Whittle first cooperated on a pilot study of five early Neolithic long barrows in southern England, showing that their construction, use and closure could be assigned to specific parts of the 38th, 37th and 36th centuries cal BC, and that their primary use was probably not for more than 1–3 generations (Bayliss and Whittle, Histories of the Dead, Cambridge Archaeological Journal , 2007). With Frances Healy, they then carried out a much wider study of the early Neolithic in Britain and Ireland, focusing on the causewayed enclosures of southern Britain. Rather than belonging to a broad span of centuries, these monumental and ceremonial gathering places were probably built between the late 38th and mid-36th centuries cal BC; while some were in primary use for up to three centuries, others lasted for only a generation — or even less time. They could be shown to follow the initial Neolithisation of Britain and Ireland and the building of the first long barrows (Whittle, Healy and Bayliss, Gathering Time, 2011).

The Times of Their Lives (2012–2017; www.totl.eu) is a further effort to demonstrate the importance of the Bayesian approach to radiocarbon-based chronology, through a series of case studies across Neolithic Europe, from the sixth to the third millennia cal BC. For the most part, we have deliberately avoided the Mesolithic- Neolithic transition, and concentrate on questions relevant to the further development of Neolithic lifeways, practices and society. The project is by design very wide-ranging, in order to reach as many different research communities as possible. We have case studies in Spain, Malta, France, Germany, Switzerland, Poland, Hungary, Serbia, Romania, Scotland and England. Cooperation with our wonderful partners across this spectrum is gratefully acknowledged. The scope of the project is also deliberately broad, ranging from studies of tells or settlement mounds, to flat settlements, to monuments such as ditched enclosures and barrows and cairns with collective burials, to regional cultural sequences and to pollenbased landscape investigations. It has proved possible to effectively use samples not only from recent and ongoing excavation projects, but also ones from much older archives (which should everywhere be maintained as a precious resource). Connecting all these strands are underlying interests in timing, duration and tempo, in the challenge of how to combine timescales, and in the nature of social change through the span of the European Neolithic.

We are publishing our studies in a long series of papers in international journals (and we thank also our team of modellers and associates: Alistair Barclay, Bisserka Gaydarska, Derek Hamilton, Frances Healy and Peter Marshall). The first are now out in Antiquity and Proceedings of the Prehistoric Society (FirstView). While we still have much to complete, highlights so far include new insights into both the long-term and the short-term.

Studies of the tells of Vinča-Belo Brdo, Serbia (with Nenad Tasić and team), and Uivar, Romania (with Wolfram Schier, Florin Draşovean and team), of the Early and Middle Neolithic sequence in the upper Rhineland, France (with Anthony Denaire and Philippe Lefranc), and of the development of the Early Copper Age complex at Valencina de la Concepcion, south-west Spain (with Leonardo Garcia Sanjuan and team) all show, in their different ways, situations of continuity over the long term, over spans of centuries. But in a Bayesian framework, it is possible to estimate the timings of beginnings and endings, for example, with much greater precision, and to break down seemingly monolithic blocks of time into smaller units, to get a measure of the tempo of change within periods of continuity. Thus the ending of tells or settlement mounds in the Carpathian basin can begin to be assigned to a series of events in the 47th and 46th centuries cal BC — the great tell of Vinča-Belo Brdo may have been one of the last to end — raising the question of the specific historical conditions in which this came about. The upper Rhineland sequence from the later sixth to the end of the fifth millennium cal BC shows much cultural continuity, but probably with a significant gap between the end of the LBK and the start of the Hinkelstein group, provoking possibilities of dramatic hiatus and abandonment, even if the causes of such a rupture remain unclear. The sequence at Valencina de la Concepcion may contain slow beginnings and then a burst of extravagant social display, before decline, in the face of a changing world round about it in the Iberian peninsula and beyond.

Similarly, our study of the vast flat settlement of Alsonyek, Hungary (with Eszter Banffy and team), is showing how a major aggregation of people did not gradually form over a period of centuries, but probably expanded very rapidly over three or four generations, reaching a peak of size and activity around 4700 cal BC, before again declining quite rapidly. This again sets the questions of what drew people together in such unusual numbers, and why this ‘coalescent community’ could not be maintained for longer. These and other studies, including of the settlements of Racot, Poland (with Arkadiusz Marciniak, Lech Czerniak and team), and Barnhouse, Orkney, Scotland (with Colin Richards and team), are producing a series of precise estimates for the duration of houses, which vary by context from a couple of decades to, on occasion, well over a human lifespan: another key insight into the tempo of Neolithic lifeways. Other studies of ditched enclosures, Chateau Percin, France (with Muriel Gandelin and team) and Klingenberg, Germany (with Ute Seidel and team), and of collective burial monuments in the Paris basin, Bury and Les Mournouards, France (with Laure Salanova, Philippe Chambon and team), are also reinforcing the recurrence of short-lived phenomena.

 It is important to underline the remaining challenges. Sometimes an optimum number of ideal samples are not available, and sometimes the shape of the calibration curve results in bi-modal distributions of date estimates, which even the best stratigraphy and material sequences cannot fully counter. It is not easy to put multi-scalar perspectives into practice. But armed with this approach, and exploiting sample choices to the full, we believe that archaeologists everywhere can leave fuzzy prehistory behind and in so doing reveal the web of connections and successions that made up past lives, in order to write much more precise chronicles for peopling the past.

Alasdair Whittle

Alasdair Whittle is a Distinguished Research Professor at Cardiff University, Wales, UK, where he has researched and taught since 1978. He has worked on many aspects of the European Neolithic and has excavated in the UK, Germany and Hungary. One of his recent projects, on the early Neolithic of central Europe, combined archaeological and scientific approaches to examine diversity in the lifeways of the LBK culture (Bickle and Whittle, 2013, The First Farmers of Central Europe ). He has written many books and monographs, including syntheses of the European evidence at a continental scale (Europe in the Neolithic: The Creation of New Worlds, 1996 ). Since 2000, he has collaborated with Professor Alexandra Bayliss, Head of Scientific Dating at Historic England (formerly English Heritage), on a series of projects based on formal chronological modelling of radiocarbon dates in a Bayesian framework. Their pilot study looked at five early Neolithic long barrows in southern England, which was followed by a major study of the early Neolithic in the UK and Ireland, focused on the southern British causewayed enclosures (Whittle, Healy and Bayliss, 2011, Gathering Time ). Since 2012, they have led the European Research Council-funded project, The Times of Their Lives (www.totl.eu), applying the Bayesian approach to a range of situations and problems across Neolithic Europe, from the sixth to the third millennia cal BC, in an effort to show that chronology can routinely be refined to the scales of lifetimes and generations — opening up new questions and more historical perspectives. Alasdair Whittle was elected a Fellow of the British Academy in 1998.
 
(Alasdair Whittle     Cardiff University    Alexandra Bayliss     Historic England)