The effects of Mid-Holocene foragers on the European oyster in Denmark.

Oysters (Ostreidae) play a pivotal role in the health and productivity of marine ecosystems. Their unique ability to filter water, provide habitat, and contribute to nutrient cycling has remained underused in many parts of Europe following the destruction of vast oyster beds in the 19th and 20th centuries. The burgeoning field of oyster restoration for aquaculture has recognized the potential of these bivalves in promoting ecosystem resilience and enhancing biodiversity. Restoring oysters to previous levels requires the establishment of ecological baselines that ideally take into account the long-term changes of animal behavior as well as the surrounding environment prior to significant human intervention, an extremely challenging task. Archaeological shell middens are invaluable baseline archives and provide exclusive insights into past ecosystems. Here, we use demographic information from over 2,000 analyzed European oyster (Ostrea edulis) shells dating from ~5,660 to 2,600 cal BCE (calibrated years BCE), the largest archaeological growth rate dataset of mollusks yet. Through the analysis of size as well as ontogenetic age, we decouple anthropogenic from environmental impacts throughout Denmark. Our data show definitive influence of oyster size-age structure through human harvesting during the Mid-Holocene, with older oysters in the Mesolithic (mean: 4.9 y) than the Neolithic (mean: 3.7 y), irrespective of changes in growth rate. Furthermore, we present the metrics for long-term sustainable harvesting of oysters across environmental and socioeconomic transitions, providing demographic targets for current oyster restoration projects and valuable context in mitigating the impact of modern climatic change.

Ancient lipids reveal continuity in culinary practices across the transition to agriculture in Northern Europe.

Farming transformed societies globally. Yet, despite more than a century of research, there is little consensus on the speed or completeness of this fundamental change and, consequently, on its principal drivers. For Northern Europe, the debate has often centered on the rich archaeological record of the Western Baltic, but even here it is unclear how quickly or completely people abandoned wild terrestrial and marine resources after the introduction of domesticated plants and animals at ∼4000 calibrated years B.C. Ceramic containers are found ubiquitously on these sites and contain remarkably well-preserved lipids derived from the original use of the vessel. Reconstructing culinary practices from this ceramic record can contribute to longstanding debates concerning the origins of farming. Here we present data on the molecular and isotopic characteristics of lipids extracted from 133 ceramic vessels and 100 carbonized surface residues dating to immediately before and after the first evidence of domesticated animals and plants in the Western Baltic. The presence of specific lipid biomarkers, notably ω-(o-alkylphenyl)alkanoic acids, and the isotopic composition of individual n-alkanoic acids clearly show that a significant proportion (∼20%) of ceramic vessels with lipids preserved continued to be used for processing marine and freshwater resources across the transition to agriculture in this region. Although changes in pottery use are immediately evident, our data challenge the popular notions that economies were completely transformed with the arrival of farming and that Neolithic pottery was exclusively associated with produce from domesticated animals and plants.

Correction to 'Organic residue analysis shows sub-regional patterns in the use of pottery by Northern European hunter-gatherers'.

[This corrects the article DOI: 10.1098/rsos.192016.].

Organic residue analysis shows sub-regional patterns in the use of pottery by Northern European hunter-gatherers.

The introduction of pottery vessels to Europe has long been seen as closely linked with the spread of agriculture and pastoralism from the Near East. The adoption of pottery technology by hunter-gatherers in Northern and Eastern Europe does not fit this paradigm, and its role within these communities is so far unresolved. To investigate the motivations for hunter-gatherer pottery use, here, we present the systematic analysis of the contents of 528 early vessels from the Baltic Sea region, mostly dating to the late 6th-5th millennium cal BC, using molecular and isotopic characterization techniques. The results demonstrate clear sub-regional trends in the use of ceramics by hunter-gatherers; aquatic resources in the Eastern Baltic, non-ruminant animal fats in the Southeastern Baltic, and a more variable use, including ruminant animal products, in the Western Baltic, potentially including dairy. We found surprisingly little evidence for the use of ceramics for non-culinary activities, such as the production of resins. We attribute the emergence of these sub-regional cuisines to the diffusion of new culinary ideas afforded by the adoption of pottery, e.g. cooking and combining foods, but culturally contextualized and influenced by traditional practices.

'Palaeoshellomics' reveals the use of freshwater mother-of-pearl in prehistory.

The extensive use of mollusc shell as a versatile raw material is testament to its importance in prehistoric times. The consistent choice of certain species for different purposes, including the making of ornaments, is a direct representation of how humans viewed and exploited their environment. The necessary taxonomic information, however, is often impossible to obtain from objects that are small, heavily worked or degraded. Here we propose a novel biogeochemical approach to track the biological origin of prehistoric mollusc shell. We conducted an in-depth study of archaeological ornaments using microstructural, geochemical and biomolecular analyses, including 'palaeoshellomics', the first application of palaeoproteomics to mollusc shells (and indeed to any invertebrate calcified tissue). We reveal the consistent use of locally-sourced freshwater mother-of-pearl for the standardized manufacture of 'double-buttons'. This craft is found throughout Europe between 4200-3800 BCE, highlighting the ornament-makers' profound knowledge of the biogeosphere and the existence of cross-cultural traditions.