The Alien Presence: Palaeoentomological Approaches to Trade and Migration Gary Andrew King PhD 2009 The Alien Presence: Palaeoentomological Approaches to Trade and Migration Gary Andrew King A thesis presented to the University of York in fulfilment of the thesis requirement for the degree of Doctor of Philosophy in Archaeology University of York Department of Archaeology September 2009 2 The alien presence: Palaeoentomological approaches to trade and migration Abstract This thesis addresses the potential of palaeoentomological remains to stand as evidence of past trade and culture contact. Three methodological tools are used to evaluate the effectiveness of insect subfossils as palaeoeconomic indicators: palaeoecology, biogeography, and isotopic analysis. Underpinning each of the methodological approaches is the premise that specific insect fauna are notably stenotopic in their distributional range. By superimposing the physiological and ecological habits of modern species over the archaeological record, they may effectively serve as analogues to interpret palaeoentomological evidence. On that basis, the archaeological presence of stenotopic insects may reliably be employed as indicators of their associated habitats. Furthermore, the examination of the archaeological remains of the specific monophagous or oligophagous species that are known to feed on human exploitable resources may provide direct or indirect evidence towards the presence of those commodities. For example, Sitophilus granarius may stand as an indication of the presence of stored cereal grains. In each of the methodological approaches, the palaeoentomological remains proved promising as a tool for suggesting probable socio-economic activity. However, the approaches differed in the precision and confidence of their results. The palaeoecological approach provided the most tentative assertions; where as the 3 isotopic method allowed for formulation of the most scientifically-grounded conclusions. In addition to the three applied methodologies, the thesis explored the potential for palaeoentomological remains to yield assayable genetic sequences. Ancient DNA was recovered from preserved Roman and medieval specimens. If aDNA preservation is widespread in palaeoentomological remains, a phylogeographic method is conceivable as a means for assessing past trade and migration. 4 Table of Contents ABSTRACT..................................................................................................................3 ACKNOWLEDGEMENTS ......................................................................................12 CHAPTER 1 INTRODUCTION AND SCOPE OF THESIS................................14 1.1 TRADE AND MIGRATION : THE ARCHAEOLOGICAL VIABILITY .......................15 1.2 THE ARCHAEOLOGICAL SIGNIFICANCE OF INSECTS .......................................19 1.3 AIMS OF THE STUDY ..........................................................................................22 1.4 APPROACHING A METHODOLOGY ....................................................................22 1.5 STRUCTURE ........................................................................................................24 CHAPTER 2 MORPHOLOGICAL AND ECOLOGICAL CONCEPTS............27 2.1 INTRODUCTION ..................................................................................................28 2.2 MORPHOLOGY ...................................................................................................28 2.2.1 The Cuticle .................................................................................................30 2.2.2 The Chitin ...................................................................................................33 2.2.3 The Head ....................................................................................................36 2.2.4 The Thorax .................................................................................................41 2.2.5 The Abdomen .............................................................................................43 2.3 IDENTIFICATION METHODS ...............................................................................44 2.3.1 Modern Insects ...........................................................................................44 2.3.2 Fossil Insects ..............................................................................................48 2.4 ECOLOGY ...........................................................................................................51 2.4.1 Components ................................................................................................53 2.4.2 Synecology ..................................................................................................55 2.4.3 Ecological Constraints ...............................................................................59 5 2.4.4 The Ecology of Invasive Species ...............................................................63 CHAPTER 3 METHODOLOGICAL REVIEW ....................................................67 3.1 INTRODUCTION ..................................................................................................68 3.2 DATA COLLECTION ...........................................................................................68 3.3 PROCESSING METHODS .....................................................................................69 3.4 PALAEOECOLOGY ..............................................................................................69 3.4.1 Theoretical Perspective ..............................................................................69 3.4.2 Background to the Methodology ...............................................................70 3.4.3 Methodology ...............................................................................................73 3.5 BIOGEOGRAPHY .................................................................................................74 3.5.1 A Brief Literature Review ..........................................................................74 3.5.2 Approaching the Problem ..........................................................................75 3.6 ISOTOPIC ANALYSES ..........................................................................................76 3.6.1 History ........................................................................................................76 3.6.2 Theoretical Basis ........................................................................................77 3.6.3 Methodology and Objectives ......................................................................80 3.7 PHYLOGEOGRAPHY ...........................................................................................82 3.7.1 The History of Ancient DNA .....................................................................82 3.7.2 The Extraction of Ancient DNA from Samples ........................................84 3.7.4 Ancient DNA Authentication Criteria .......................................................86 3.7.5 Targeting Mitochondrial DNA: The Aims of the Project .........................87 CHAPTER 4 THE PALAEOECOLOGICAL APPROACH: ...............................90 4.1 INTRODUCTION ..................................................................................................91 4.2 CASE STUDY 1: 7-15 SPURRIERGATE , YORK (SITE CODE : 2000:584) ..............93 6 4.2.1 Introduction ................................................................................................93 4.2.2 Processing Methods ...................................................................................93 4.2.3 Results and Analysis of the Data ...............................................................94 4.2.4 Palaeoenvironmental Reconstruction of Roman Spurriergate ..............106 4.2.5 Palaeoclimatic Reconstruction ................................................................112 4.2.6 Discussion: The Environment and Climate of 7-15 Spurriergate and Implications for Culture Contact .....................................................................114 4.2.7 Summary ...................................................................................................116 4.3 CASE STUDY : 16-22 COPPERGATE , YORK PERIOD 4B ...................................117 4.3.1 Introduction ..............................................................................................117 4.3.2 Background and Processing Methods .....................................................117 4.3.3 Results and Analysis of Data ...................................................................120 4.3.4 Palaeoenvironmental Reconstruction of Anglo-Scandinavian Coppergate ............................................................................................................................140 4.3.5 Palaeoclimatic Reconstruction ................................................................148 4.3.6 Discussion: The Environment and Climate of Period 4b 16-22 Coppergate and Implications for Culture Contact ..........................................149 4.3.7 Summary ...................................................................................................155 4.4 CONCLUSION ....................................................................................................156 CHAPTER 5 GRAIN PESTS: AN ARCHAEOBIOGEOGRAPHICAL ACCOUNT OF THE HISTORY OF THEIR DISPERSAL................................159 5.1 INTRODUCTION ................................................................................................160