Inland Ertebølle Culture: the importance of aquatic resources and the freshwater reservoir effect in radiocarbon dates from pottery food crusts

Abstract

SummaryThe Ertebølle culture is a late Mesolithic hunter-gatherer-fisher culture in southern Scandinavia, northern Germany and Poland. Archaeological finds as well as scientific analyses of humans and their artefacts indicate the great importance of aquatic resources, both marine and freshwater, to Ertebølle subsistence.In northern Germany, modern freshwater fish samples can have very high apparent radiocarbon ages (up to 3000 years). If such dramatic 'freshwater reservoir effects' also existed during the late Mesolithic, they could lead to artificially old radiocarbon dates for the bones of Ertebølle humans and domestic dogs, and for carbonised food crusts on cooking pots. Conversely, if we can demonstrate radiocarbon age 'offsets' in such samples, we can often attribute them to the exploitation of freshwater food resources.This article discusses methods of identifying freshwater resources in prehistoric pottery, including radiocarbon reservoir effects. We consider the results of radiocarbon, stable isotope and elemental analyses of food crusts on prehistoric pottery from four sites in the Alster and Trave valleys: Kayhude, Schlamersdorf, Bebensee and Seedorf.

Stone Age Pottery Chronology in the Northeast European Forest Zone: New AMS and EA-IRMS Results on Foodcrusts

“…Figure 7 shows the elemental concentrations in foodcrust extracts. The high %N values, and correspondingly low C/N values in most foodcrusts, are typical of extracted foodcrusts from hunter-gatherer-fisher pottery in the Baltic region (Philippsen 2013a; Philippsen and Meadows 2014; J Meadows, unpublished data). Figure 8 shows the foodcrust stable isotope ratios.…”

Late Mesolithic Narva Stage in Estonia: Pottery, Settlement Types and Chronology

“…Lanting & van der Plicht 1998;Arneborg et al 1999;Eriksson 2004;Fischer et al 2007;Olsen et al 2010;Piezonka et al 2013). However, the same problems may apply to dating food crusts as well: when aquatic ingredients have been stored or cooked in vessels, food crusts and lipids absorbed in potsherds are also subject to possible reservoir effect (Fischer & Heinemeier 2003;Hartz et al 2012;Philippsen 2013;Philippsen & Meadows 2014). These problems with dating pottery food crust have been recently acknowledged in the eastern Baltic archaeology (Pesonen et al 2012;Zhulnikov et al 2012;Piličiauskas & Heron 2015).…”

“…Most intriguing from the dates we have so far is the oldest date of Narva-type pottery in Estonia (ca 5500 cal BC) obtained from carbonized organic remains on potsherd found from Kääpa dwelling site. However, recent work has exemplified the relevance of considering a threat of reservoir effect and the importance of identifying substances analysed when dating pottery food crusts (Fischer & Heinemeier 2003;Hartz et al 2012;Philippsen 2013;Philippsen & Meadows 2014). Thus, it was necessary to reconsider previous food crust dates from Kääpa and test the potential of reservoir offset at the site.…”

Aquatic Resources in Foodcrusts: Identification and Implication

“…Some dates obtained on the base-soluble fraction of foodcrusts from the Ertebølle site at Kayhude in northern Germany, which gave older 14 C dates than the total crust, perhaps indicate contamination from the burial environment. Philippsen and Meadows (2014) have highlighted the clear differences in coastal and inland foodcrust dates and bulk isotope measurements obtained on Ertebølle pottery from northern Germany. A more cautionary note has been sounded by Boudin et al (2009Boudin et al ( , 2010 in their investigation of Late Mesolithic wetland sites in NW Belgium.…”