title: Spatial variability in sulphur isotope values of archaeological and modern cod (Gadus morhua).
abstract: BACKGROUND
  This study presents the first sulphur isotope data of modern and archaeological cod (Gadus morhua) bone collagen, undertaken to identify large-scale spatial variability of significance as both baseline values for studies of human diet and a potential variable in isotope-based studies of fish trading.
  
  
  METHODS
  Collagen was extracted from modern and archaeological cod bones using a weak HCl solution and analysed for its sulphur isotopic composition by isotope ratio mass spectrometry (IRMS).
  
  
  RESULTS
  The archaeological cod have sulphur isotope values ranging from +9.1‰ to +18.2‰, whereas values for modern specimens range from +14.8‰ to +18.3‰. The modern data show values implying less freshwater influence, consistent with their offshore catch locations, but also corroborate some of the regional variability evident from the archaeological evidence.
  
  
  CONCLUSIONS
  The archaeological data have a large range of sulphur isotope values compared with the modern populations, probably indicating they were taken from a wide range of geographic locations, including both coastal and offshore locales. They show broad trends of regional difference that may relate to both the fish populations targeted (e.g. 'inshore' versus 'offshore') and the baseline values of the local ecosystem (e.g. degree of freshwater input from river systems).
authors.affiliation: Department of Anthropology, University of British Columbia, 6303 N.W. Marine Drive, Vancouver, BC, V6T 1Z1, Canada; Department of Human Evolution, Max-Planck-Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany.
authors.forename: Olaf
authors.initials: O
authors.lastname: Nehlich
authors.forename: James H
authors.initials: JH
authors.lastname: Barrett
authors.forename: Michael P
authors.initials: MP
authors.lastname: Richards
mesh_terms: D000818:Animals; D001106:Archaeology; D001842:Bone and Bones / Q000737:chemistry*; D003094:Collagen / Q000737:chemistry*; D048389:Gadus morhua; D013058:Mass Spectrometry; D009792:Oceans and Seas; D012537:Scandinavian and Nordic Countries; D013460:Sulfur Isotopes / Q000032:analysis*; D006113:United Kingdom
chemical_list: D013460:Sulfur Isotopes; D003094:Collagen