RECONSTRUCTION OF PREHISTORIC DIET IN BRITISH COLUMBIA USING STABLE-CARBON ISOTOPIC ANALYSIS Brian Stewart Chisholm B.A. Simon Fraser University 1 977 THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in the Department of Archaeology @ Brian Stewart Chisholm 1986 SlmlN FRASER WI VERSITY Mvember 1986 All rigttsremml. Thiswork may not be rep- in whole or in part, by photoapy or other means, without permission of the author. Approval Name: Brian Stewart Chisholm Degree: Ph.5. Archaeology Title: Reconstruction of prehistoric diet in British Columbia using stable-carbon isotopic analysis. Examining Committee: Chairman: Prof. Phi 1 Hobler Dr. D.Erle Nelson Dr. Richard Shutler Jr. ' )# Senior Supervisor - / Dr. Rolf Mathewes Department of Biology Simon Fraser University Date Approved: November 19 , 198 6 b' " Dr. Tom Pedersen External Examiner Department of Oceanography University of British Columbia PARTIAL COPYRIGHT LICENSE 1 hereby grant to Slmn Fraser Unlverslty the right to lend my thesis, proJect or extended essay (the tltle of which is shown below) to users ot the Simon Fraser University Library, and to make partial or single copies only for such users or In response to a request from the library of any other university, or other educational Institution, on its own behalf or for one of Its users. I further agree that permission for multiple copying of thls work for scholarly purposes may be granted by me or the Dean of Graduate Studies. It is understood that copying or publication of this work for financial gain shall not be allowed without my written permlsslon. Title of Thesis/Project/Extended Essay Author: (signature) ( name (date) iii Abstract information on prehistoric diet can be extremely useful for understanding human behaviour as it relates to food acquisition. In British Columbia prehistoric diet has been inferred from ethnographic, archaeological and zoo- archaeological evidence. However, lack of quantified data makes it difficult to determine the degree to which people relied on marine species for their protein, or to compare people from different sites and time periods. This study uses a new approach, the application of stable carbon isotope analysis of human bone collagen, to obtain such quantified data. Following investigation of the applicability and variability of the analytical technique, ethnographic and archaeological evidence was used to identify dietary species representing marine and terrestrial a1 temat ives. Samples of those species were taken for each of a nwnber of different locales and environments, and representative isotope ratios determined for both marine- and terrestrial-based diets. Isotope ratios for prehistoric humans were then compared to those for the two alternative diets in order to determine the human's degree of reliance on marine species as a protein source. Results indicate that prehistoric British Columbian coastal dwellers obtained about 90 r 10% of their protein from marine species, while people along the Fraser and Thompson Rivers in Interior British Columbia obtained only about 40 to 60 (2 101% of their protein from marine species, specifically salmon. People in areas away from major salmon streams obtained some of their protein from marine species although the amount was much less. These proportions do not appear to have changed signlf icantly for the last 5000 years. However, some differences have been observed in results, between females and males, adults and children, and geographic areas. t v Acknoyvledgements I would like to thank Erle Nelson, Richard Shutler Jr., and Jon Driver for the support and advice they provided as members of my supervisory committee. I also thank Tom Brown, Keith Hobson, Martin Knyf, Nancy Lovell, Henry Schwarcz, Mark Skinner and Bryan Snow for discussions and advice. Samples of dietary species and prehistoric human bone, were provided by Sylvia Albright, Andrew Barton, Gaye Burton, Roy Carlson, Joanne Curtin, Phil Hobler, Richard Lazenby, Gordon Mohs, Val Patenaude, Mike Rousseau and Mark Skinner, all of who were in the Archaeology Department at the time. Further samples and data were provided by Jerry Cybulski of the National Museum of Man, Ottawa, Nick Gessler of Queen Charlotte City, Dick 301 of the Animal Care Facility, Simon Fraser University, Grant Keddie and Tom Loy of the British Columbia Provincial Museum, Thomas Madokoro and a number of unidentified fishermen from Steveston, Tom Oleman of the Seton Lake Band, Dave Pokotylo of the University of British Columbia, Arnoud Stryd of Arcas Associates, and Phil Whitehead of the Canadian Wildlife Service. Rick Howard assisted with sample preparation. Analytical facilities were provided by Henry Schwarcz at McMaster University, and by Pieter Grootes at the University of Washington. Martin Knyf of McMaster University and Trevor Saling of the Unlverslty of Washington did many of the measurements, so that I only had to make two trips to Hamilton. Mickey Yang of the Biology Department did the amino acid and elemental analysis of extracted samples. I thank my fellow graduate students for encouragement and interest, and Ingrid Bell for her humour and friendship. The research was supported by the Natural Sciences and Engineering Research Council of Canada. Table of Contents Abstract iii Acknow Iedgements iv Table of Contents v List of Tables ix ~istof Figures X Introductton 1 Diet reconstructions 2 Problems with the standard approaches to paleodiet studies 4 New approaches 4 Scope of this study 5 Part I Carbon isotope analysis and its application in British Columbia 7 1 Overview of the carbon isotope technique History of the technique Definition of 613c, fractionation and standards Carbon reservolrs and plants Herbivores, carnivores and food chains 2 Application of the technique and the importance of variability 14 Variations in reservoirs, food chalns and dietary specles 15 Materials analyzed: dietary species 20 Materials analyzed: collagen 20 Chemical makeup of collagen 24 I The effects of diagenetic processes on collagen The diet - consumer increment 'ADC' Variability in consumer populations Summary 3 Requirements of and problems with the laboratory procedures Collagen extraction Quality control of extracttons Sample measurement Summary 4 Tests of the methods used Sample analysis Combustion of the samples to obtain CO2 Collagen extraction Determination of gelatin purity Tests of lipid extraction Variation in one individual's gelatin Preparation of dietary samples Discussion and summary 5 Deterrnlnatlon of the diet - consumer increment, 'AN' I 6 The applicability of the technique, particularly in British Columbia 6.1 Dietary species Preltminary analyses Dietary sample requirements and sample selection Dietary sample results 6.2 Human population results in British Columbia 6.3 Interpreting the a13c results for humans Errors on the proportion determinations Summary 7 Conclusions about the technique and its application, particularly in British Colwnbia 81 The technique 81 . Diet a1 ternat ive values in British Columbia Results for human populations Proportton determinations smary Part It Prehistoric diet in British Columbia 1 Archaeologlcal evidence for paleodiet in Brittsh Columbia The coast The interior Human samples I 2 Human results from British Columbia 2.1 The coastal results The Namu - Central Coast people The Prince Rupert area samples The Queen Charlotte Island results Hesquiat results Gulf of Georgia sites Summary and discussion of Coastal results 2.2 lnterior results lnterior results: summary Proportion determinations British Columbia humans: summary and discussion Appendix A Results for individual samples of dietary species 132 Appendix B l ndiv t dual human results 138 References 148 List of Tables I Expected collagen values for modern consumers of specif lc diets Values of 'AN' that have been reported and used in the literature Comparison of combust ion methods Comparison of gelatin extract ion methods C/N values, %C, and %N for extractfon method test samples Amlno acid analysis of 5 representative samples Effects of removing lipids from modem bone samples Reproducibility of results for different extractions from the same individual Results of the 'aoc' study Results for the 46 paired samples used to test lipid extraction North - south comparison for terrestrial species Marine species results by regions Summary of diet species results for British Columbia 14 Combined Central Coast results 15 Prince Rupert area Individual results 16 Queen Charlotte Island results 17 Hesquiat results 18 Gulf of Georgia area results 19 Summary of coastal results 20 lnterlor results 2 1 Proportfons of marine protein In diets: Coastal indtviual averages 22 Proportions of marine protein in diets: Interior individual averages List ,of Figures 1 Proportions of modern C3 versus marine herbivore species in a diet 13 2 Locations of coastal sites sampled 100 3 Locations of interior sites sampled 116 1 Introduction I One of the major concerns of archaeologists is the study of human subsistence. Subsistence studies are concerned with the interactions of people, their technologies, and their local environments and biotas. Subsistence affects their day to day life, and to varying degrees, their social organization and cultural adaptations. Availability of food types can affect the location of sites and may lead to site specialization. Seasonal fluctuations in food availability may necessitate seasonal change in food procurement patterns and hence result in seasonal transhumance.