Stable carbon and nitrogen isotopic ratios (δ
13
C, δ
15
N) in bone collagen of archaeological skeletal finds are indicators of the protein sources in individuals’ basic diet. Isotopic sourcing ...allows us to quantify the biomass contribution of major dietary components and to differentiate between the source contribution of various animal species (domesticates, game). We re-evaluated previously published isotopic signatures in skeletons from three burial sites in Bavaria, dated from Late Antiquity to Early Mediaeval times (Erding-Klettham, Erding-Altenerding, Straubing-Bajuwarenstraße) by use of a mixing model. The result is a more detailed reconstruction, supported by contextual evidence, of both early subsistence economies and individual dietary preferences. We were able to confirm relationships between non-local dietary behaviour and foreign cultural influences (grave goods and artificial cranial modification) that have previously been suggested by the burial context and DNA analyses and that are plausibly explained by migration events. Moreover, we differentiated early and late immigrants from each other, requiring a re-evaluation of the earlier interpretation of exogamy. In addition, individual dietary preferences indicate even more migration events and social stratifications that could not previously be identified by the archaeological evidence alone.
Abstract The diagnosis of starvation in children or adults is an important topic in paediatric and geriatric medicine, and in law assessment. To date, few reliable techniques are available to ...reconstruct the onset and duration of undernourishment, especially in cases of wilful neglect or abuse. The intention of this research project is to introduce a method based on isotopic analysis to reconstruct nutritional life histories and to detect starvation. For this purpose the specific signature of stable carbon and nitrogen isotopes in human hair samples is investigated and measured in the course of serious nutritional deprivation. Previous study of our research group on anorectic patients has shown that incremental hair analyses can monitor the individual nutritional status of each patient. Increasing δ15 N-values indicate the catabolism of bodily protein and are associated with a very low BMI. In contrast, the changes of the δ13 C values and BMI were in phase, which can be linked to the lack of energy in the consumed diet and the break down of body fat deposits. These findings were now applied to various forensic cases, in which severe starvation occurred recently prior to death. We are aiming at establishing an unbiased biomarker to identify the individual timeframe of nutritional deprivation to detect and prevent starvation.
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•Isotopic sourcing permits an estimate of the quantity of major dietary protein sources.•Resource quantification gives clues to ancient subsistence strategies.•The introduction of the ...Neolithic Package into Europe was remarkably flexible.•Adopting the new while maintaining parts of the mesolithic life-style served nutrition security.
The Neolithic Transition in Europe was more complex and flexible as previously suggested. Around 6800 BCE, this new economy had reached Greece where some of the earliest European Neolithic sites are evidenced. To monitor this milestone of human living conditions, previously published conventional bivariate interpretations of collagen stable carbon and nitrogen isotope ratios in archaeological skeletons were subjected to an isotopic sourcing in an attempt to quantify the most important protein sources. This way, the process of changing subsistence economies during the earliest Neolithic in Europe should be assessed. We were capable of approximating the protein biomass contribution by vegetal food and to evaluate the proportion of meat derived from domesticates and game, thereby telling hunting from husbandry. According to the results, the Neolithic Transition in the Mediterranean was not characterized by a conspicuous change in nutritional habits although the Neolithic Package had arrived there in its fully developed form. Rather, slow and gradual adaptations that preserved major components of a hunting and gathering lifestyle are observable. This way, a stable subsistence was guaranteed in the course of the adaptation to a producing economy.
Rationale
Methods for multi‐isotope analyses are gaining in importance in anthropological, archaeological, and ecological studies. However, when material is limited (i.e., archaeological remains), it ...is obligatory to decide a priori which isotopic system(s) could be omitted without losing information.
Methods
We introduce a method that enables feature ranking of isotopic systems on the basis of distance‐based entropy. The feature ranking method is evaluated using Gaussian Mixture Model (GMM) clustering as well as a cluster validation index (“trace index”).
Results
Combinations of features resulting in high entropy values are less important than those resulting in low entropy values structuring the dataset into more distinct clusters. Therefore, this method allows us to rank isotopic systems. The isotope ranking depends on the analyzed dataset, for example, consisting of terrestrial mammals or fish. The feature ranking results were verified by cluster analysis.
Conclusions
Entropy‐based feature ranking can be used to a priori select the isotopic systems that should be analyzed. Consequently, we strongly suggest that this method should be applied if only limited material is available.
Palaeobiodiversity research based on stable isotope analysis in coastal environments can be severely hampered by the so-called “sea spray” effect. This effect shifts the isotopic signal of ...terrestrial individuals towards too marine values. It is commonly agreed upon that sea spray influences sulphur stable isotopes. However, we were able to approximate a remarkable sea spray effect also in carbon and oxygen stable isotopes of bone carbonate previously. In the present study we could approximate a minimum sea spray effect of about 13.9% even present in oxygen isotope values of bone phosphate, which was validated by Gaussian Mixture Model (GMM) clustering. This approximated value is by some magnitudes smaller than the minimum sea spray effect approximated for both δ13Ccarb and δ18Ocarb, and quite close to the sea spray detected for δ34Scoll in a previous study. It may therefore be interpreted as purer minimum sea spray signal compared to the approximation in bone carbonate. Furthermore, detection of sea spray in δ18Ophos can serve as additional validation of the effect present in bone carbonate, which is more prone to diagenetic alteration compared to bone phosphate. Moreover, the presence of the sea spray effect in both δ18Ocarb and δ18Ophos demonstrates that sea spray can be taken up by terrestrial mammals not only via food (δ18Ocarb) but also via drinking water (δ18Ophos). Finally, this study once more confirmed that calculation of δ18Ophos from δ18Ocarb values using a fixed oxygen isotope spacing (Δδ18O) can be highly misleading, especially in coastal environments affected by sea spray.
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•First approximation of sea spray effect in δ18Ophos of bone apatite•Detection of a relatively pure sea spray effect in bone phosphate•Sea spray detected in δ18Ophos serves as validation of the effect in carbonate.•Uptake of sea spray signal via both food (δ18Ocarb) and drinking water (δ18Ophos)•Determination of oxygen isotope spacing (Δδ18O) after sea spray correction
Abstract Human cremation is a common funeral practice all over the world and will presumably become an even more popular choice for interment in the future. Mainly for purposes of identification, ...there is presently a growing need to perform trace analyses such as DNA or stable isotope analyses on human remains after cremation in order to clarify pending questions in civil or criminal court cases. The aim of this study was to experimentally test the potential and limitations of DNA and stable isotope analyses when conducted on cremated remains. For this purpose, tibiae from modern cattle were experimentally cremated by incinerating the bones in increments of 100 °C until a maximum of 1000 °C was reached. In addition, cremated human remains were collected from a modern crematory. The samples were investigated to determine level of DNA preservation and stable isotope values (C and N in collagen, C and O in the structural carbonate, and Sr in apatite). Furthermore, we assessed the integrity of microstructural organization, appearance under UV-light, collagen content, as well as the mineral and crystalline organization. This was conducted in order to provide a general background with which to explain observed changes in the trace analyses data sets. The goal is to develop an efficacious screening method for determining at which degree of burning bone still retains its original biological signals. We found that stable isotope analysis of the tested light elements in bone is only possible up to a heat exposure of 300 °C while the isotopic signal from strontium remains unaltered even in bones exposed to very high temperatures. DNA-analyses seem theoretically possible up to a heat exposure of 600 °C but can not be advised in every case because of the increased risk of contamination. While the macroscopic colour and UV-fluorescence of cremated bone give hints to temperature exposure of the bone's outer surface, its histological appearance can be used as a reliable indicator for the assessment of the overall degree of burning.
Yersinia pestis, the etiologic agent of the disease plague, has been implicated in three historical pandemics. These include the third pandemic of the 19th and 20th centuries, during which plague was ...spread around the world, and the second pandemic of the 14th-17th centuries, which included the infamous epidemic known as the Black Death. Previous studies have confirmed that Y. pestis caused these two more recent pandemics. However, a highly spirited debate still continues as to whether Y. pestis caused the so-called Justinianic Plague of the 6th-8th centuries AD. By analyzing ancient DNA in two independent ancient DNA laboratories, we confirmed unambiguously the presence of Y. pestis DNA in human skeletal remains from an Early Medieval cemetery. In addition, we narrowed the phylogenetic position of the responsible strain down to major branch 0 on the Y. pestis phylogeny, specifically between nodes N03 and N05. Our findings confirm that Y. pestis was responsible for the Justinianic Plague, which should end the controversy regarding the etiology of this pandemic. The first genotype of a Y. pestis strain that caused the Late Antique plague provides important information about the history of the plague bacillus and suggests that the first pandemic also originated in Asia, similar to the other two plague pandemics.
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