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The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgementTown of the source. The thesis is to be used for private study or non- commercial research purposes only. Cape Published by the University ofof Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University AN INVESTIGATION OF STABLE SULPHUR ISOTOPES AS A PALAEODIETARY INDICATOR IN SOUTH AFRICA Town Cape Malia Johnson of University Thesis presented for the degree of Master of Science In the Department of Archaeology University of Cape Town March, 2011 DECLARATION I know the meaning of plagiarism and declare that all the work in the document, save for that which is properly acknowledged, is my own. Town Cape of University Signature: ___________________________ Date: _______________________________ ii TABLE OF CONTENTS Declaration ................................................................................................................................ ii Table of Contents .....................................................................................................................iii List of Tables ............................................................................................................................ v List of Figures .......................................................................................................................... vi Abstract ................................................................................................................................... vii Acknowledgements................................................................................................................viii Chapter I: Introduction. ........................................................................................................... 1 Chapter 2: Archaeology in the Western Cape Province, South Africa..................................... 8 Climate and Food Resources of the LSA Western Cape ProvinceTown ..................................... 8 Later Stone Age People in the Western Cape Province.................................................... 14 /eology of the Western Coast Region and Site Details................................................... 17 /eology of the Southern Coast Region and SiteCape Details.................................................. 20 /eology of the Inland Region and Siteof Details................................................................. 22 Summary ........................................................................................................................... 25 Chapter 3: Literature Review of Stable Sulphur Isotopes....................................................... 26 Sulphur Isotopes in the Environment................................................................................ 27 Sulphur IsotopesUniversity in Plants................................................................................................. 31 Sulphur Metabolism and Sulphur Isotopes in Animals and Humans ............................... 32 Sulphur Stable Isotope Studies in Archaeology................................................................ 35 The 6Sea Spray Effect7 and Coastal Environments.......................................................... 40 Chapter 4: Methodology ....................................................................................................... 46 Sample Selection............................................................................................................... 46 Collagen E8traction and Stable Carbon and Nitrogen Isotope Analysis at UCT ............. 51 Collagen E8traction at MPI-EVA ..................................................................................... 53 iii Preparation for IRMS Analysis......................................................................................... 55 Chapter 5: Results ................................................................................................................... 57 Collagen Quality Assessment ........................................................................................... 57 Sulphur Stable Isotope Values of Animal Samples .......................................................... 63 Sulphur Isotope Values of Human Samples...................................................................... 69 Comparison of UCT and MPI-EVA Data......................................................................... 76 Summary of Results .......................................................................................................... 82 Chapter 6: Discussion and Conclusions.................................................................................. 84 The 6Sea Spray Effect7 .................................................................................................... 88 Estuarine Environments .................................................................................................... 90 Inland Environments .........................................................................................................Town 94 Suggestions for Future Work ............................................................................................ 96 Conclusions.......................................................................................................................Cape 98 References ............................................................................................................................of 101 University iv LIST OF TABLES Table 1: Sample Identification................................................................................................ 48 Table 2: Stable Carbon, Nitrogen, and Sulphur Isotope Data ................................................ 59 Table 3: Recent Material......................................................................................................... 62 Table 4: Comparison of UCT and MPI >12C and >11N Measurements................................... 77 Table 5: Problematic Samples................................................................................................ 81 Table 6: Sites with both 5umans and Animals....................................................................... 96 Town Cape of University v LIST OF FIGURES Figure 1: Map of Sites and Sampling Locations, Western Cape Province, South Africa ........ 5 Figure 2: Geological Map of Project Area, Western Cape Province ........................................ 9 Figure 3: Potential Sulphur Sources in Marine Ecosystems ................................................... 28 Figure 4: Potential Sulphur Sources in Terrestrial Ecosystems.............................................. 29 Figure 5: >2.S Values of All Samples by /eographic Region ................................................ 64 Figure 6: >2.S and >11N Values for 18 Animal Samples from Robberg ................................ 66 Figure 7: Site Distribution of >2.S vs. >12C for Human Samples............................................ 70 Figure 8: Archaeological Site Distribution with Drainage BasinsTown and Stream Order ............ 72 Figure 9: ,0Sr/,3Sr vs. >2.S of 6 5uman Samples Plotted with /eographic Locations........... 75 Figure 10: Location, Ecosystem, & >2.S Values for Animals and Humans ........................... 87 Figure 11: Animal and Human >12C, >11N, and >Cape2.S Triangular Plot..................................... 89 of University vi ABSTRACT The purpose of this thesis is to assess the use of stable sulphur isotope analysis as a tool for studying the diet and mobility of Later Stone Age people in the Western Cape Province of South Africa. Stable carbon D>12CE and nitrogen D>11NE isotope ratios have long been analyFed for palaeodietary studies. Anly recently have technological advances made the routine analysis of sulphur isotopes D>2.SE in small samples possible, enabling measurement of valuable archaeological specimens without undue destruction. For this study 23 archaeological animal bones and 20 archaeological human skeletons were analyFed, as well as 7 modern faunal specimens from areas whereTown it was difficult to obtain suitable archaeological material. Samples were selected from a number of coastal localities on both the southern DIndian Acean) and western DAtlantic Acean) coastlines, as well as from several inland sites. This is the firstCape archaeologically oriented sulphur isotope study to attempt to map >2.S values acrossof a landscape on this scale. >2.S values of marine animals ranged from 15.2 to 17.6G Dn=12), in good agreement with previous studies. Coastal terrestrial animals varied from 8.5 to 20.2„ Dn=18), reflecting the 6sea spray effect7 but also Din some areasE the influence of local geology and/or estuarine and marshland environments. Animals from the Fold Belt Mountains had high >2.S, and only inland of theseUniversity mountains were values distinctly lower. Values for humans tended to cluster with those for animals from the same site, e8cept humans from sites with a significant brackish water source had low >2.S, while browsing animals from the same sites did not. >2.S measurements therefore have the potential to identify distinct feeding habitats within coastal environments. Further analysis of animal and plant samples is reIuired to fully understand the patterning in >2.S values. vii ACKNOW LEDGEMENTS I am incredibly thankful to my supervisor, Professor Judith Sealy, for providing the opportunity and materials