Abstract
Compound-specific amino acid carbon-isotope compositions have shown particular promise for elucidating dietary behaviors in complex environmental contexts, and may also be able to mitigate the effect of many of the limitations inherent to palaeodietary reconstructions. Here, we investigate the efficacy of compound-specific amino acid isotopic proxies in characterizing the consumption of different dietary protein sources using amino acid carbon-isotope compositions for humans and fauna from Rössberga (Early to Middle Neolithic), Köpingsvik (Mesolithic and Middle Neolithic), and Visby (Medieval Period), Sweden. We also assess the explanatory capabilities of an isotopic mixing model when used with essential amino acid carbon-isotope compositions of humans and local fauna. All three isotopic proxies distinguished among humans from the three sites consistently and informatively, and were able to enhance the broad interpretations made using bulk isotopic compositions. The mixing model palaeodietary reconstruction revealed considerable diversity in relative protein source contributions among individuals at both Köpingsvik and Visby. Comparing the mixing model for bulk carbon- and nitrogen-isotope compositions to the model for essential amino acid isotopic compositions further demonstrated the likelihood of underestimation and overestimation of marine protein consumption for both aquatic-dominant and mixed marine-terrestrial diets when using bulk isotopic compositions.
Highlights
Carbon- and nitrogen-isotope analyses of archaeological human and faunal remains have made important contributions to palaeodietary and palaeoecological reconstruction for decades, but, in recent years, there has been a growing interest in using compound-specific amino acid isotopic analysis to extend the limits of palaeodietary interpretation (Choy et al 2010; Corr et al 2005, 2008; Fogel and Tuross 2003; McCullagh et al 2006; Naito et al 2010; Smith et al 2009; Styring et al 2010, 2015)
Numerous factors impose important limitations on palaeodietary reconstruction from bulk protein isotopic compositions, of particular importance here are the potential for variable tissue-diet isotopic offsets, the effect of the nonprotein portion of diet on body protein isotopic composition, and the influence of both nutritional quality and protein source
We investigate the explanatory capabilities of IsoSource, a commonly used mixing model, when it is used with essential amino acid carbon-isotope compositions from humans and local fauna
Summary
Carbon- and nitrogen-isotope analyses of archaeological human and faunal remains have made important contributions to palaeodietary and palaeoecological reconstruction for decades, but, in recent years, there has been a growing interest in using compound-specific amino acid isotopic analysis to extend the limits of palaeodietary interpretation (Choy et al 2010; Corr et al 2005, 2008; Fogel and Tuross 2003; McCullagh et al 2006; Naito et al 2010; Smith et al 2009; Styring et al 2010, 2015). If a small amount of marine protein is consumed, with the remainder of total dietary protein derived from a terrestrial source, the carbon-isotope compositions of collagen (δ13Ccol) may be quite low, obscuring the marine carbon contribution. Nondietary factors, can have significant impact on the δ15N values of humans, other consumers, and primary producers Biological factors such as illness, traumatic injury, starvation, rapid growth, physiological stress, and pregnancy can all cause changes in nitrogen metabolism and in human and faunal tissue nitrogen-isotope compositions (Fuller et al 2004a, b; 2005; Heaton et al 1986; Hedges and Reynard 2007; Hobson et al 1993; Mekota et al 2006; Olsen et al 2014; Petzke et al 2006; Schwarcz et al 1999; White and Armelagos 1997; Williams et al 2011). Aridity and the application of animal dung as manure can increase the δ15N values of plants and increase consumer tissue δ15N values (Bogaard et al 2007; Fraser et al 2011; Gröcke et al 1997)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
