. (2015) Best practice methodology for 14C calibration of marine and mixed terrestrial/marine samples. Quaternary Geochronology, 27, pp. 164-171. Copyright © 2015 Elsevier B.V.A copy can be downloaded for personal non-commercial research or study, without prior permission or charge Content must not be changed in any way or reproduced in any format or medium without the formal permission of the copyright holder(s) This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Abstract: There is a lack of detailed guidance in the published literature on how to calibrate 14 C measurements made on marine or mixed marine/terrestrial (primarily human remains) samples. We describe what we consider to be the best approach towards achieving the most accurate calibrated age ranges, using the most appropriate ΔR and percentage marine diet estimates, and associated, realistic error terms on these values. However, this approach will increase the calibrated age range(s) by fully accounting for the variability in both the model and the material. While the discussion is based on examples from the UK and Iceland, the same fundamental arguments can be applied in any geographic location largely devoid of C 4 plants as the high δ AbstractThere is a lack of detailed guidance in the published literature on how to calibrate 14 C measurements made on marine or mixed marine/terrestrial (primarily human remains) samples. We describe what we consider to be the best approach towards achieving the most accurate calibrated age ranges, using the most appropriate ∆R and percentage marine diet estimates, and associated, realistic error terms on these values. However, this approach will increase the calibrated age range(s) by fully accounting for the variability in both the model and the material. While the discussion is based on examples from the UK and Iceland, the same fundamental arguments can be applied in any geographic location largely devoid of C 4 plants as the high δ 13C values from such plants can make identification of marine intake difficult to determine.

ABSTRACT. We present δ 13 C, δ 15 N, and δ 34 S measurements on archaeological human and animal bone collagen samples from a shell midden dating to the Neolithic ca. 4000-3500 cal BC, together with measurements on modern fish and shellfish. These data were used in conjunction with the Bayesian mixing model, Food Reconstruction Using Isotopic Transferred Signals (FRUITS), to reconstruct human diet at the site. We demonstrate the importance of using a geographically appropriate faunal baseline in stable isotope paleodietary studies, and suggest that Neolithic individuals at this site consumed up to ca. 21% of dietary protein from marine resources, despite stable isotope ratios that imply a wholly terrestrial diet. This marine resource consumption does not significantly shift the radiocarbon ( 14 C) dates of these individuals, so although we must consider the use of marine resources at the site, the chronology that has previously been established is secure. The δ 13 C and δ 15N measurements from the archaeological herbivore bone collagen indicate that it is unlikely they ate plants enriched with fertilisers such as manure or seaweed. The δ 34 S values reveal a sea-spray effect; therefore, in this instance, δ 34 S cannot be used as a dietary indicator but can be used to demonstrate the likely locality of the fauna.

The results of carbon and nitrogen isotope analysis from two medieval populations are presented here, in a study investigating dietary habits within a medieval hospital population in England. A multi-methodological approach was taken in order to attempt to identify a distinct group diet within the medieval hospital of St Giles, Brough, Yorkshire, and examine the reasons why the dietary habits within the institution may have been noticeably different from that of a comparative lay population. Following the results and tentative conclusions of a study conducted by Müldner and Richards (2005), it was hypothesised that religious fasting rules would result in there being evidence of greater consumption marine fish at St. Giles than at the rural township of Box Lane, Pontefract, Yorkshire. While more dietary variation was found at the hospital, it can be seen that the differences in δ 13 C and δ 15 N isotope values vary in relation to the animal baselines. Thus, differences between the human populations can be attributed to geological and environmental factors as opposed to dietary differences. Highlights • We summarise evidence of diet in medieval towns, monasteries and hospitals. • δ 13 C and δ 15 N analysis was used to recreate the diet of two medieval populations. • Inter-population difference in isotope ratios was attributed to environmental baseline variation. • Social diversity may explain intra-population variation in individuals buried at St Giles.