UNIVERSITAT AUTÒNOMA DE BARCELONA FACULTAT DE FILOSOFIA I LLETRES DEPARTAMENT DE PREHISTÒRIA DOCTORAT EN ARQUEOLOGIA PREHISTÒRICA SPACE-TEMPORAL ANALYSIS OF RADIOCARBON EVIDENCE AND ASSOCIATED ARCHAEOLOGICAL RECORD: FROM DANUBE TO EBRO RIVERS AND FROM BRONZE TO IRON AGES by Giacomo Capuzzo Thesis submitted for the degree of Doctor in Prehistoric Archaeology Supervisor: Prof. Juan Antonio Barceló Álvarez, UAB Co-Supervisor: Prof. Giovanni Leonardi, Università degli Studi di Padova 2014 2 A mia nonna 3 4 CONTENTS 1 ARCHAEOLOGY, TIME AND SPACE: CULTURAL HOMOGENIZATION AT 9 THE END OF LATE BRONZE AGE IN EUROPE? 1.1 Introduction 9 1.2 Expansion and movement in Archaeology 13 1.3 European Bronze Age as a case study 18 2 ARCHAEOLOGICAL EVIDENCES FROM DANUBE TO EBRO 29 2.1 Introduction 29 2.2 North of the Alps area 31 2.3 Northern Italy 34 2.4 Southern France 37 2.5 The North-East of Iberian Peninsula 39 3 ARCHAEOLOGICAL EVIDENCES FROM THE BRONZE TO THE IRON AGE 43 3.1 Introduction 43 3.2 The Bronze Age and the transition to the Iron Age in Protohistoric Europe 45 3.3 The so called Urnfield culture: cremation burials and new pottery typologies. From the 48 traditional views to nowadays 3.4 From East to West or the other way round 55 3.5 The substitution of populations hypothesis 60 3.5.1 Linguistic data and palaeolinguistic reconstruction 60 3.5.2 Genetic markers and population flows 66 3.6 The adaptive hypothesis: population growth and/or decline as a result of climatic change 72 3.7 The social, economic and political hypotheses. A criticism of the substitution of 77 population hypothesis 3.7.1 The circulation of raw materials, in particular tin and bronze 77 3.7.2 The circulation of prestige items 80 3.7.3 The circulation of ideas: the armed elites 83 3.7.4 Exchanges of individuals: wars and marriage alliances 85 3.7.5 Center-periphery and the world system theory 88 5 4 HOW TO MEASURE THE OCCURRENCE OF HISTORICAL EVENTS? 91 RADIOCARBON DATING 4.1 Introduction 91 4.2 The fundamentals of radiocarbon dating 92 4.3 Uncertainty of the radiocarbon dating 94 4.3.1 Gaussian errors: measuring problems 95 4.3.2 Non-Gaussian errors: calibration 98 4.3.2.1 The “Hallstatt disaster” 107 4.3.3 Representativeness of a sample 110 4.3.3.1 Errors in the field 110 4.3.3.2 The “old-wood effect” and the “reservoir effect” 112 4.4 Dating historical events 114 4.5 From theory to method. Estimating the duration of a historical period 124 4.6 Bayesian analysis of radiocarbon measurements 126 5 THE EUBAR DATABASE 133 5.1 Introduction 133 5.2 Location in the physic space and in time 134 5.3 Site, material and archaeological context 135 5.3.1 The importance of social, cultural and economic variables 136 5.3.2 Archaeological and time markers 139 5.3.2.1Vases with handles with vertical expansion 140 5.3.2.2 Fluted pottery 142 5.3.2.3 Carinated cups 145 5.3.2.4 Biconical vessels 148 5.3.2.5 Decoration with helicoidal ribs 148 5.3.2.6 Decoration with solar motive 149 5.3.2.7 Decoration with meanders 150 5.3.2.8 Decoration with chevrons 151 5.3.2.9 Decoration with zig-zag 151 5.4 The database: contents and preliminary inspection 152 5.5 Testing the reliability of data: sample prescreening 155 6 REVIEW OF THE PERIODIZATION: BAYESIAN ANALYSIS OF 14C-DATED 159 ARCHAEOLOGICAL CONTEXTS FROM NORTHERN ITALY, SOUTHERN FRANCE AND THE NORTH-EAST OF IBERIAN PENINSULA 6.1 Introduction 159 6.2 Sites, contexts and sampling 160 6 6.3 Data analysis 161 6.3.1 Sample and context prescreening 161 6.3.1.1 Northern Italy 163 6.3.1.2 Southern France 165 6.3.1.3 North-East of Iberian Peninsula 166 6.3.2 Modeling methods (modeling Bronze Age and Iron Age transition) 167 6.3.3 Definition, Identification and Removal of Archaeological and Analytical 168 Outliers from the Sequences 6.3.3.1 Northern Italy 169 6.3.3.2 Southern France 172 6.3.3.3 North-East of Iberian Peninsula 175 6.4 Discussion 175 6.4.1 Northern Italy 177 6.4.2 Southern France 178 7 FROM THE ALPS TO THE MEDITERRANEAN: A STATISTICAL ANALYSIS OF 181 TEMPORAL CONTINUITIES AND DISCONTINUITIES 7.1 The study of population trends in the Bronze Age and in the Iron Age transition 181 7.2 Temporal continuities and discontinuities in the EUBAR database 184 7.3 Theoretical and methodological remarks 195 8 QUANTIFYING THE RATE OF ADOPTION OF “INNOVATIONS” IN WESTERN 201 EUROPE DURING BRONZE AGE 8.1 The number of radiocarbon dates as an estimation of the number of adopters. Theoretical 201 and methodological remarks 8.2 Growth, diffusion and the adoption of innovations across time 206 8.3 Quantifying the adoption of a new funerary ritual 213 8.4 Quantifying the adoption of new cultural elements 217 8.4.1 Fluted pottery 218 8.4.2 Vases with handles with vertical expansion 220 8.4.3 Pottery with helicoidal ribs decoration 223 8.4.4 Biconical vessels 225 8.4.5 Carinated cups 226 8.4.6 Daggers and knives 227 8.4.7 Fortified settlements 230 8.5 The classical logistic model of the diffusion of an innovation 231 8.6 Fitting the explanatory model to archaeological data 235 8.7 Testing the reliability of the growth in the estimated probability of archaeological events 239 across time 7 9 THE ADOPTION OF “INNOVATIONS” IN WESTERN EUROPE DURING 243 BRONZE AGE. THE PROBABILITIES OF A SPATIALLY DEPENDENT DIFFUSION PROCESSES 9.1 Characterizing expansive phenomena in historical research 243 9.2 Modeling the first occurrence of cremation burials between 1800 and 800 BC in 252 Protohistoric Europe 9.3 Modeling the first occurrence of vases with handles with vertical expansion between 262 1800 and 800 BC and from the Danube to the Ebro River 9.4 Modeling the first occurrence of fluted pottery between 1800 and 800 BC and from the 265 Danube to the Ebro River 10 CONCLUSIONS AND FUTURE PERSPECTIVES 267 10.1 The historical problem 267 10.2 Archaeological evidence. Radiocarbon data 268 10.3 Testing the temporality of archaeological periods 269 10.4 Interpreting the spatio-temporal frequency of radiocarbon dated archaeological contexts 270 10.5 Adoption of innovations and diffusion in Europe between 1800 and 750 BC 274 10.6 A suggested explanation of cultural standardization between 1200 and 750 BC 277 10.7 A computer model of Bronze Age diffusion and adoption of innovations 280 ACKNOWLEDGEMENTS 289 REFERENCES 291 8 1 ARCHAEOLOGY, TIME AND SPACE: CULTURAL HOMOGENIZATION AT THE END OF LATE BRONZE AGE IN EUROPE? 1.1 Introduction The main goal of archaeological research is to reconstruct social actions in the past from a more or less coherent sub-sample of material remains from that past context having survived in the present. Our purpose is to understand why someone made something somewhere and somewhen. In the case of Prehistoric and Protohistoric Archaeology, to attain such a goal, the only source of information at our disposal is the archaeological record. Although part of such information is lost due to post-depositional processes, our knowledge depends exclusively on how we are able to analyze the archaeological deposit, both in the field and in the laboratory. We must be aware that the sediment alone and the material remains buried in it do not give directly a solution to our questions. They are just the data. It is only through scientific and statistical analysis that we will obtain answers to our hypothesis. In this work our aim is to investigate the causes of space-time distributions of archaeological observables. We take for granted that the cause of an observed spatial distribution is not “space”, but the nature of social action that generated the precise location and accumulation of material evidences at specific places and specific moments, and the local circumstances at the moment of the action. If an action A took place at some location L, and at some time T, it should be related with the occurrence of observed material evidences around L that can be determined were generated at time T, but also with observed material evidences located elsewhere, and at T-1 and T+1, to explain why A took place where it took place and not in another location and at another place (Barceló 2005; Maximiano 2007). The proper location of archaeological materials in time and in space is a necessary requisite for any archaeological investigation. Nevertheless, although huge advances have been made in recent years, precise measuring of time and place are not the norm in archaeological research. Time and space concepts are frequently defined in a qualitative way by archaeologists. For instance, in the archaeological literature time is often 9 described in a qualitative way using the traditional phases of conventional chronology based on typological analysis of human artifacts. Regarding space, the spatial location of a site is frequently addressed without any mention to georeferentiation, just a toponym. Such an approach does not allow us to analyze the variability of space-time distributions of settlements, burials and pottery, among others. Therefore, in this work we want to adopt a different focus. Temporal locations are defined by the results of the radiocarbon dating with their associated standard errors, and dendro-chronological calibration correction. Spatial location, which describes where something (such as a collection) is physically located, are defined by geospatial coordinates such as latitude and longitude, expressed either in meters (UTM coordinates) or in decimal degrees.