Beyond faith: Biomolecular evidence for changing urban economies in multi-faith medieval Portugal.

OBJECTIVES: During the Middle Ages, Portugal witnessed unprecedented socioeconomic and religious changes under transitioning religious political rule. The implications of changing ruling powers for urban food systems and individual diets in medieval Portugal is poorly understood. This study aimed to elucidate the dietary impact of the Islamic and Christian conquests. MATERIALS AND METHODS: Radiocarbon dating, peptide mass fingerprinting (ZooMS) and stable isotope analysis (δ13 C, δ15 N) of animal (n = 59) and human skeletal remains (n = 205) from Muslim and Christian burials were used to characterize the diet of a large historical sample from Portugal. A Bayesian stable isotope mixing model (BSIMM) was used to estimate the contribution of marine protein to human diet. RESULTS: Early medieval (8-12th century), preconquest urban Muslim populations had mean (±1SD) values of -18.8 ± 0.4 ‰ for δ13 C 10.4 ± 1 ‰ for δ15 N, indicating a predominantly terrestrial diet, while late medieval (12-14th century) postconquest Muslim and Christian populations showed a greater reliance on marine resources with mean (±1SD) values of -17.9 ± 1.3‰ for δ13 C and 11.1 ± 1.1‰ for δ15 N. BSIMM estimation supported a significant increase in the contribution of marine resources to human diet. DISCUSSION: The results provide the first biomolecular evidence for a dietary revolution that is not evidenced in contemporaneous historical accounts. We find that society transitioned from a largely agro-pastoral economy under Islamic rule to one characterized by a new focus on marine resources under later Christian rule. This economic change led to the naissance of the marine economy that went on to characterize the early-modern period in Portugal and its global expansion.

Dating the last Middle Palaeolithic of the Crimean Peninsula: New hydroxyproline AMS dates from the site of Kabazi II.

Radiocarbon dating of bone and charcoal from sites dating to the Middle and Upper Paleolithic is challenging due to low residual levels of radiocarbon. This means that small amounts of contaminating carbon can wield a great influence over accuracy unless they are fully removed. The site of Kabazi II in the Crimea is important because radiocarbon dates previously obtained from bones in archaeological horizons that date to the Western Crimean Mousterian (WCM) are surprisingly young. We redated the same samples using a single compound dating method that focuses on extracting and dating the amino acid hydroxyproline. We show that single amino acid dates produce significantly older determinations than those that use bulk collagen pretreatment procedures. Our results suggest that instead of dating to 35,000-40,000 cal BP, the bones actually date to >50,000 cal BP. This implies that the WCM at this site is much older than previously thought. In light of these current findings, we considered the dates of other key Crimean sites and concluded that in the absence of reliable pretreatment methods, it would be wise to consider many of them minimum ages. We conclude that there is little robust evidence to suggest Neanderthals were present in the Crimea after 40,000 cal BP.

Reevaluating the timing of Neanderthal disappearance in Northwest Europe.

Elucidating when Neanderthal populations disappeared from Eurasia is a key question in paleoanthropology, and Belgium is one of the key regions for studying the Middle to Upper Paleolithic transition. Previous radiocarbon dating placed the Spy Neanderthals among the latest surviving Neanderthals in Northwest Europe with reported dates as young as 23,880 ± 240 B.P. (OxA-8912). Questions were raised, however, regarding the reliability of these dates. Soil contamination and carbon-based conservation products are known to cause problems during the radiocarbon dating of bulk collagen samples. Employing a compound-specific approach that is today the most efficient in removing contamination and ancient genomic analysis, we demonstrate here that previous dates produced on Neanderthal specimens from Spy were inaccurately young by up to 10,000 y due to the presence of unremoved contamination. Our compound-specific radiocarbon dates on the Neanderthals from Spy and those from Engis and Fonds-de-Forêt demonstrate that they disappeared from Northwest Europe at 44,200 to 40,600 cal B.P. (at 95.4% probability), much earlier than previously suggested. Our data contribute significantly to refining models for Neanderthal disappearance in Europe and, more broadly, show that chronometric models regarding the appearance or disappearance of animal or hominin groups should be based only on radiocarbon dates obtained using robust pretreatment methods.

Multidisciplinary investigations of the diets of two post-medieval populations from London using stable isotopes and microdebris analysis.

This paper presents the first multi-tissue study of diet in post-medieval London using both the stable light isotope analysis of carbon and nitrogen and analysis of microdebris in dental calculus. Dietary intake was explored over short and long timescales. Bulk bone collagen was analysed from humans from the Queen's Chapel of the Savoy (QCS) (n = 66) and the St Barnabas/St Mary Abbots (SB) (n = 25). Incremental dentine analysis was performed on the second molar of individual QCS1123 to explore childhood dietary intake. Bulk hair samples (n = 4) were sampled from adults from QCS, and dental calculus was analysed from four other individuals using microscopy. In addition, bone collagen from a total of 46 animals from QCS (n = 11) and the additional site of Prescot Street (n = 35) was analysed, providing the first animal dietary baseline for post-medieval London. Overall, isotopic results suggest a largely C3-based terrestrial diet for both populations, with the exception of QCS1123 who exhibited values consistent with the consumption of C4 food sources throughout childhood and adulthood. The differences exhibited in δ15Ncoll across both populations likely reflect variations in diet due to social class and occupation, with individuals from SB likely representing wealthier individuals consuming larger quantities of animal and marine fish protein. Microdebris analysis results were limited but indicate the consumption of domestic cereals. This paper demonstrates the utility of a multidisciplinary approach to investigate diet across long and short timescales to further our understanding of variations in social status and mobility.

Ancient proteins from ceramic vessels at Çatalhöyük West reveal the hidden cuisine of early farmers.

The analysis of lipids (fats, oils and waxes) absorbed within archaeological pottery has revolutionized the study of past diets and culinary practices. However, this technique can lack taxonomic and tissue specificity and is often unable to disentangle signatures resulting from the mixing of different food products. Here, we extract ancient proteins from ceramic vessels from the West Mound of the key early farming site of Çatalhöyük in Anatolia, revealing that this community processed mixes of cereals, pulses, dairy and meat products, and that particular vessels may have been reserved for specialized foods (e.g., cow milk and milk whey). Moreover, we demonstrate that dietary proteins can persist on archaeological artefacts for at least 8000 years, and that this approach can reveal past culinary practices with more taxonomic and tissue-specific clarity than has been possible with previous biomolecular techniques.

Barcoding the largest animals on Earth: ongoing challenges and molecular solutions in the taxonomic identification of ancient cetaceans.

Over the last few centuries, many cetacean species have witnessed dramatic global declines due to industrial overharvesting and other anthropogenic influences, and thus are key targets for conservation. Whale bones recovered from archaeological and palaeontological contexts can provide essential baseline information on the past geographical distribution and abundance of species required for developing informed conservation policies. Here we review the challenges with identifying whale bones through traditional anatomical methods, as well as the opportunities provided by new molecular analyses. Through a case study focused on the North Sea, we demonstrate how the utility of this (pre)historic data is currently limited by a lack of accurate taxonomic information for the majority of ancient cetacean remains. We then discuss current opportunities presented by molecular identification methods such as DNA barcoding and collagen peptide mass fingerprinting (zooarchaeology by mass spectrometry), and highlight the importance of molecular identifications in assessing ancient species' distributions through a case study focused on the Mediterranean. We conclude by considering high-throughput molecular approaches such as hybridization capture followed by next-generation sequencing as cost-effective approaches for enhancing the ecological informativeness of these ancient sample sets.This article is part of the themed issue 'From DNA barcodes to biomes'.