Lethal Threshold: The Evolutionary Implications of Middle Pleistocene Wooden Spears ANNEMIEKE GISELLE MILKS UCL INSTITUTE OF ARCHAEOLOGY PHD Author’s Declaration I, Annemieke Giselle Milks, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. Abstract This thesis provides empirical data pertaining to the use of the earliest weapons in the archaeological record, which are a collection of plain wooden spears dating to the Middle Pleistocene. These weapons have been variously interpreted as objects for scavenging, hunting and self-defence. It is important to test these functional interpretations with a multi-disciplinary data-led approach, as these interpretations have implications for theories on the origins of human hunting, shifts in cognition, social structures and language. This is the first time a systematic, holistic approach to these artefacts has been taken, and is timely as several of the key sites of the period are currently undergoing further detailed analysis, resulting in reinterpretations of human behaviours during Middle Pleistocene. In this document the performance of these artefacts is addressed through three research strands. The archaeological strand looks at both wooden spears as well as potential hunting lesions from their use. The approach to these include qualitative and quantitative analyses. The ethnographic strand comprises a review of the literature pertaining to the use of wooden spears in pre-industrialised societies. Alongside this, a morphometric analysis of a large sample of wooden spears from museum collections in the UK and Australia is presented for comparative purposes. The third strand consists of a multi-phase experimental programme, examining human performance when using replicas as thrusting and throwing spears; effectiveness of the spears on large mammals; hunting lesions resulting from use of the spears on large mammals; hammerstone impact damage to scapulae addressing questions of equifinality; and guided free-fall impact drop tests to better understand spear tip design. Results from the different approaches are brought together and compared, to better address the archaeological record from the Middle Pleistocene, including both the weapons themselves and potential zooarchaeological signatures resulting from their use. 5 6 Table of Contents Chapter 1. Introduction 33 1.1 Overview of thesis 33 1.2 Aims and objectives 34 1.3 Research framework: scope and limitations 35 1.4 Theoretical and methodological approaches 36 1.5 Thesis structure 37 Chapter 2. Weapons and human evolution: historical background and patterns of human predation in the European Middle Pleistocene 39 2.1 A short ‘prehistory’ of weaponry: historical background 39 2.1.1 Introduction to historical background 39 2.1.2 Historical references to the use of weaponry in human evolution 40 2.1.2.1 The Antiquarians 40 2.1.2.2 Darwin: two legs good 42 2.1.2.3 Killer Apes! 42 2.1.2.4 ‘Man’ the toolmaker, ‘man’ the hunter 45 2.1.3. The hunting and scavenging debate: 1970s-present 46 2.1.3.1 Binford, Bunn, and Beyond: new models 46 2.1.3.2 Weaponry, human evolution, and ‘behavioural modernity’ 48 2.2 The European Middle Pleistocene: humans and animals 49 2.2.1 Still a ‘muddle in the middle’? European Middle Pleistocene hominins and their toolkits 50 2.2.2 Hunting in the Middle Pleistocene: evidence for hunting, prey physiology and prey behaviours 56 2.2.2.1 Evidence for hominin hunting behaviours in the Eurasian MP 56 2.2.2.2 Middle Pleistocene prey and modern analogues 57 2.2.2.3 Prey behaviours: social structures and anti-predator responses 58 2.2.3 Predator-prey relationships: hunting strategies and the importance of environment and landscape 62 2.2.3.1 Hunting strategies: social hunting, multiple predation, and attack strategies 62 2.2.3.2 Palaeolandscapes and palaeoenvironments 65 2.3 Evidence related to early weaponry from palaeoanthropology, primatology, and behavioural sciences 66 7 2.3.1 The biomechanics of weapon use 66 2.3.2 Contributions from primate studies 69 2.3.3 Behavioural studies: decoupling patterns of violence with human predation 71 2.4. Summary of background review 72 Chapter 3. Evaluating hand-delivered wooden spears and their use: theoretical and methodological approaches 73 3.1 Weaponry and human evolution: definitions and models 73 3.1.1 Weaponry definitions 73 3.1.2 Models of weapon delivery systems 75 3.1.3 Early evidence of weaponry 78 3.1.4 Identifying and evaluating prehistoric weaponry 78 3.2 Theoretical and methodological approaches to evaluating hand-delivered wooden spears 80 3.2.1 Relating morphometrics to function of wooden spears 80 3.2.2 Approaches to identifying hunting lesions 81 3.2.3 Ethnography and wooden spears: a thorny relationship 83 3.2.3.1 Reliability of the ethnographic record for the interpretation of Middle Pleistocene weapons 83 3.2.3.2 Methodological approaches to ethnography of wooden spears 85 3.2.4 Experimental analogies on the use of wooden spears 86 3.2.4.1 Weapon mechanics 87 3.2.4.2 Terminal ballistics 87 3.2.4.3 Wound ballistics 87 3.3 Summary 93 Chapter 4. Archaeological wooden spears: morphometrics and traces of use 95 4.1. Introduction 95 4.1.1 Background on sites and artefacts 96 4.1.1.1 Clacton-on-Sea, Essex (UK) 97 4.1.1.2 Schöningen, Lower Saxony (Germany) 104 4.1.1.3 Lehringen, Lower Saxony (Germany) 110 4.1.1.4 Monte Verde II (Chile) 114 4.1.1.5 Additional Pleistocene and Holocene sites with possible wooden spears 114 4.2 Materials and Methods 116 4.2.1 Materials 116 8 4.2.2 Methods 118 4.3 Results 120 4.3.1 Clacton Spear 120 4.3.2 Schöningen spears 128 4.3.3 Lehringen spear 134 4.3.4 Comparative analysis of the sample of archaeological spears 138 4.4 Discussion 145 4.4.1 Reviewing the evidence for wooden spears in the archaeological record 145 4.4.2 Design and functional interpretations of archaeological wooden spears 146 4.4.3 Discard of archaeological wooden spears 147 4.4.4 Implications for behavioural patterns 147 Chapter 5. Middle Pleistocene hunting lesions: a rare phenomenon 149 5.1 Introduction 149 5.1.1 Background on sites and artefacts 150 5.1.1.1 Boxgrove, West Sussex (UK) 151 5.1.1.2 Swanscombe, Kent (UK) 155 5.1.2 The function and anatomy of ungulate scapulae 158 5.1.3 Interpreting potential Middle Pleistocene hunting lesions 161 5.1.3.1 Experimentally produced hunting lesions and untipped wooden spears 161 5.1.3.2 Hominin assemblage modification: hammerstone impacts for marrow and grease extraction 163 5.2 Materials and Methods 164 5.2.1 Materials 164 5.2.1.1 Boxgrove scapula and scans 164 5.2.1.2 Swanscombe scapula 168 5.2.2 Methods 169 5.2.2.1 Descriptive analysis 170 5.2.2.2 Quantitative analysis 174 5.3 Results 176 5.3.1 Descriptive analysis 176 5.3.1.1 Descriptive analysis of Boxgrove scapula fragment 176 5.3.1.2 Descriptive analysis of Swanscombe scapula 178 5.3.2 Quantitative Analysis 180 5.3.2.1 Dimensions of Boxgrove damage 180 5.3.2.2 Dimensions of Swanscombe damage 180 5.3.2.3 Bevelling of Boxgrove scapula 180 5.3.2.4 Bevelling of Swanscombe scapula 182 9 5.4 Discussion 183 5.4.1 Assessing the Boxgrove scapula 183 5.4.2 Assessing the Swanscombe scapula 183 Chapter 6. The ethnographic record: revising characterisations of the use and morphometrics of hand-delivered wooden spears 185 6.1 Literature Review of ethnography and wooden spears 186 6.1.1 Introduction to the literature review 186 6.1.2 Limitations of previous approaches: false equivalencies and selectivity 186 6.2 Materials and methods: Dataset for ethnographic literature review 189 6.3 Main findings of the literature review 190 6.3.1 Global distribution and function of wooden spears 190 6.3.2 Thrusting and hand-throwing of wooden spears for use in hunting and violence 196 6.3.3 Environments and prey 199 6.3.4 Effectiveness of wooden spears 204 6.3.5 Manufacturing and curation 206 6.4 Summary and critical appraisal of findings from literature review 207 6.5 Museum-based study of ethnographic wooden spears 210 6.5.1 Introduction to the morphometric study of ethnographic wooden spears 210 6.5.2 Previous published morphometric data of ethnographic wooden spears 210 6.6 Materials and methods 213 6.6.1 Limitations of ethnographic spear dataset 213 6.6.2 Materials: collections and selection criteria 214 6.6.3 Methods: measurement and analysis of the ethnographic spears 215 6.7 Results of the morphometric study 215 6.7.1 morphometrics 215 6.7.2 Comparison of ethnographic sample with archaeological wooden spears 227 6.8 Discussion 231 6.9 Summary of the ethnographic evidence of the use of wooden spears 232 Chapter 7. Exploring the mechanics of hand-delivered spears: Human performance trials in thrusting and throwing 235 7.1 Introduction 235 7.1.1 Previous experimental work on the mechanics of hand-delivered spears 236 10 7.1.2 Spear thrusting and throwing techniques 243 7.2 Human performance trial: spear thrusting 251 7.2.1 Introduction: experiment questions and secondary aims 251 7.2.2 Materials and Methods 252 7.2.2.1 Spear replicas 252 7.2.2.2 Target 256 7.2.2.3 Human participants 256 7.2.2.4 Experimental setup and data collection 257 7.2.2.5 Data analysis 258 7.2.3 Results 259 7.2.3.1 Spears 259 7.2.3.2 Depth of penetration into PermaGelTM 260 7.2.3.3 Participants 260 7.2.3.4 Impact velocity 260 7.2.3.5 Force 262 7.2.3.6 Force and velocity relationship 266 7.2.4 Discussion of human performance thrusting trial 267 7.3 Human performance trial: spear throwing 269 7.3.1 Introduction: experiment questions and secondary aims 269 7.3.2 Materials and Methods 270 7.3.2.1 Experiment location, setup and data acquisition 270 7.3.2.2 Spear replicas 271 7.3.2.3 Target 271 7.3.2.4 Human participants 272 7.3.2.5 Data analysis 273 7.3.3 Results 275 7.3.3.1 Velocity and kinetic energy 275 7.3.3.2 Effective distance 281 7.3.3.3 Flight trajectories 285 7.3.4 Discussion of human performance throwing trial 289 7.3.4.1 Velocity 289 7.3.4.2 Effective distance 290 7.3.4.3 The mechanics of wooden spears in flight 291 7.3.4.4 Early spears as throwing weapons 292 7.4 Summary of human performance trials of hand-delivered wooden spears 292 Chapter 8.