Strontium, oxygen, and carbon isotope variation in modern human dental enamel

Reconstructing prehistoric lifeways using multi-Isotope analyses of human enamel, dentine, and bone from Legaire Sur, Spain

Megalithism has been repetitively tied to specialised herding economies in Iberia, particularly in the mountainous areas of the Basque Country. Legaire Sur, in the uplands of Álava region, is a recently excavated passage tomb (megalithic monument) that held a minimum number of 25 individuals. This study analysed the carbon, nitrogen, oxygen, and strontium isotope ratios of 18 individuals, in a multi-tissue sampling study (successional tooth enamel sampling, incremental dentine sampling, and bulk bone collagen sampling). The results provide a high-resolution reconstruction of individual mobility, weaning, and dietary lifeways of those inhumed at the site. Oxygen and strontium isotope analysis suggest all individuals come from a similar, likely local, geological region, aside from one biological female who presents a notably different geographical birthplace, weaning, and dietary life history than the rest of the burial population. Comparisons to other nearby megalithic sites (∼35km as the crow flies), located in a valley area, reveal that, whilst sharing the same mortuary practices, these individuals held notably different lifeways. They highlight notably earlier ages of cessation of nursing (≤2 years at Legaire Sur vs. ≥4 years in other megalithic tombs), and a greater dependence on pastoralism than previously observed in lowland megalithic graves. The results from Legaire Sur reveal the complexity of the Late Neolithic-Chalcolithic transition in north-central Iberia, categorising yet another separate socio-economic group with distinctive lifeways inhabiting the region.

Mobility and community at Mesolithic Lake Onega, Karelia, north-west Russia: insights from strontium isotope analysis

This study investigates the underlying mechanisms driving the formation of the largest known burial site of the Northern European Mesolithic, Yuzhniy Oleniy Ostrov (YOO). Radiogenic strontium isotope analysis (87Sr/86Sr) was used to identify group dynamics within the cemetery and examine the site's place within local and supra-regional networks. The analysis of 57 humans and 31 animals was supported by the creation of an environmental baseline which identified four key geological zones and defines the strontium characteristics of Lake Onega. Only two individuals had strontium values indicating time spent outside of Lake Onega's northern shores, where the majority of the burial population is likely to have resided. These results suggest that the YOO cemetery predominantly served as a burial place for those with semi-permanent residence in this area, with no significant evidence for gender-based relocation patterns indicative of patri- or matrilocal residency. However, materials seem to have travelled towards Lake Onega even over great distances and the presence of the two outlier individuals suggests these exchanges also involved long-distance travel of people. Our results align with an increasing number of studies that suggest a high degree of residential stability for Late Mesolithic foraging groups relying primarily on aquatic resources, yet simultaneously places the Lake Onega community within a wider Mesolithic communication network.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12520-024-02129-8.

Bioarchaeology and evidence of violence from a precolonial later stone age communal burial in South Africa

This study reports on the bioarchaeology and evidence of interpersonal violence in a group of archaeological skeletons found near Ladismith, Western Cape, South Africa. The co-mingled skeletal remains derive from at least ten individuals of varying ages and both sexes. Overlapping radiocarbon dates on three individuals place them in the first half of the 15th century CE, pre-dating first European contact at the end of that century. Three juvenile crania have perimortem perforations, the locations of which indicate violent deaths. The sizes and shapes of the lesions suggest impact by a blade at least 110mm long and 50mm wide but with edges only 2mm thick. Based on these dimensions, we hypothesise that this was a metal-tipped spear. The nearest metal-working communities at this time lived approximately 500 km away, implying long-distance trade or exchange. δ13C, δ15N and 87Sr/86Sr values indicate that this was a heterogenous group of individuals who had spent their early lives in different locations and consumed varied diets, who had come together and were living in or travelling through the Ladismith area at the time of their deaths. This finding extends the timeframe and location for the practice of communal burial in the Holocene of southern Africa and provides additional support for the hypothesis that communal burials in this region tend to be associated with violence.

Enhancing the contemporary human and water isotope reference database for the Netherlands: New insights from Sr-O-C-N-H isotope data

The determination of an individual's geographic origin is an essential aspect of forensic investigations. When primary identifiers cannot be used to make a positive identification, isotope analysis can be utilized to provide new leads. Modern reference data are essential for accurate interpretation of human isotopic data in terms of diet and origin. This article presents Sr-O-C-N-H isotope data of modern individuals (hair, dental enamel, and dentine collagen) and drinking water from the Netherlands. The δ15N values of human hair fall within the range of values observed worldwide and cannot be utilized to differentiate from other countries. Distinct disparities in the hair δ13C are evident between European countries and other regions, making it possible to exclude the Netherlands as a region of origin. Comparing Dutch dental isotope data to those of other nations has proven difficult due to the limited availability of reference data. The same limitation applies to tap water δ2H data.

Sr-Pb isotope differences in pre- and post-burial human bone, teeth, and hair keratin: implications for isotope forensics

The isotopic signatures of human tissues can provide valuable information on geographic origin for medicolegal investigations involving unidentified persons. It is important to understand the impact of diagenetic processes on isotopic signatures, as alterations could result in incorrect estimation of geographic origin. This study examines alterations in isotope signatures of different tissues of five human body donors studied throughout decomposition at the Forensic Anthropology Research Facility (FARF), San Marcos, TX. Two body donors were buried, two were placed in open pits, and one was first allowed to naturally mummify and then buried. Remains were recovered after a period of 7-34 months. The preplacement and post-recovery Sr-Pb isotope data of scalp hair, bone (iliac and tibia), and tooth enamel and dentine were compared. The hair samples record significant shifts in Sr-Pb isotope compositions, with hair keratin Pb isotope composition shifting towards the Pb signature of local soil samples. Hair keratin Sr isotope compositions were altered by the burial environment and possibly also by the lab sample cleaning method. The spongy iliac bone samples show inconsistencies in the recoverability of the preplacement Sr-Pb isotope signatures. The post-placement signatures of the buried donors show slight elevation over preplacement signatures. The post-placement signatures of donors placed in open pits are significantly elevated. The tibia and dental samples record the most consistent isotopic data with the least alteration. These more densely mineralised elements show good recoverability of the preplacement isotope signatures in burials and open pits and are thus deemed better targets for forensic investigative purposes.

Osteological, multi-isotope and proteomic analysis of poorly-preserved human remains from a Dutch East India Company burial ground in South Africa

Skeletal remains discovered in Simon's Town, South Africa, were hypothesised as being associated with a former Dutch East India Company (VOC) hospital. We report a novel combined osteological and biochemical approach to these poorly-preserved remains. A combined strontium (87Sr/86Sr), oxygen (δ18OVPDB) and carbon (δ13CVPDB) isotope analysis informed possible childhood origins and diet, while sex-specific amelogenin enamel peptides revealed biological sex. Osteological analyses presented evidence of residual rickets, a healed trauma, dental pathological conditions, and pipe notches. The combined isotope analyses yielded results for 43 individuals which suggested a diverse range of geological origins, including at least 16% of the population being non-local. The inclusion of δ13CVPDB had intriguing implications for three individuals who likely did not have origins in the Cape Town region nor in Europe. Peptide analysis on the dental enamel of 25 tested individuals confirmed they were all biologically male. We suggest that isolated enamel may provide crucial information about individuals' pathological conditions, geographical origins, diet, and biological sex. These data further demonstrated that a combined approach using multiple osteological and biochemical methods is advantageous for human remains which are poorly preserved and can contextualise a site with little direct evidence.

Bilateral hip dysplasia in a South African male: A case study from the 17-18th century

OBJECTIVE

To identify, critically analyse and describe severe bilateral skeletal pathology involving the ossa coxae of an individual from historic era Cape Town.

MATERIALS

A single individual from the University of Cape Town's Human Skeletal Repository was analysed under research approval (HREC# 035/2021).

METHODS

An osteobiography was constructed, radiocarbon dating and isotopic analyses were conducted. Pathological description and contextualised disability analyses followed, along with differential diagnosis. The pelvis and femora were visualised macroscopically and radiographically.

RESULTS

This individual was a non-European middle-aged adult male who lived in the 17-18th centuries CE. Morphological changes showed hypoplastic hips with collapsed femoral heads and neoacetabulae. A diagnosis of developmental dysplasia of the hips (DDH) was made. Then a contextualised disability analysis including consideration of the clinical and functional impacts of the condition were applied. No signs of maltreatment, physiological stress or persistent infections were present. His bones were well developed, illustrating mobility and use.

CONCLUSIONS

He developed DDH early in life and lived through adulthood, and his strong, healthy bones suggest resilience, some mobility and contribution to society through less physically demanding tasks.

SIGNIFICANCE

Value for palaepathological analyses to inform and understand disability and culturally significant health mediation to offer a more objective interpretation and improve understanding of past people. It expands our understanding of the presence of DDH globally and in Africa and provides insight into disease impact for individuals with bilateral expression.

SUGGESTIONS FOR FUTURE RESEARCH

Further contextual research is required.

LIMITATIONS

Poor scene recovery hindered in-depth care analysis and interpretation of the condition.

Paired stable carbon and oxygen isotope analyses of human enamel for forensic human geolocation: An exploratory study

Stable carbon isotope analysis has proven utility for reconstructing dietary information in humans in past populations. The usefulness of stable carbon for forensic geolocation has been little investigated, largely because of the globalization of the human diet seemingly rendering it inconsequential. This study queried this assumption at a country-wide level on a known sample group. Stable carbon isotope values were obtained from human enamel with known biographical and geographical information to determine whether stable carbon, when paired with stable oxygen isotope values, could differentiate Canadians from non-Canadians. Samples originating outside of Canada were separated into three regions, and a linear discriminant analysis was used to generate discriminant functions that best separate the regions according to the stable carbon and oxygen isotope values. The results revealed two functions, where the first function explained 92.1% and the second 7.9% of the variance. Although some overlap in stable carbon and oxygen values was observed for individuals from both the United States and Canada, differences were observed between those from Canada and other geographical regions. This study demonstrated that pairing the dietary isotope carbon with the geolocator stable oxygen isotope, produced an interesting separation geographically, one that might well be helpful when attempting a geolocation query on unknown human remains.

Provenancing antiquarian museum collections using multi-isotope analysis

Many of the most significant archaeological sites in Europe were excavated by antiquarians over one hundred years ago. Modern museum collections therefore frequently contain human remains that were recovered during the nineteenth and early twentieth centuries. Here we apply multi-isotope analysis (⁸⁷Sr/⁸⁶Sr, δ ¹⁸O, δ ¹³C, δ ¹⁵N) and ¹⁴C dating to evaluate the provenance of human remains within a collection that is thought to have been recovered from one of the most important archaeological sites in Britain. Excavated in 1910, the site of Coldrum in Kent is a megalithic burial monument that may be one of the earliest sites associated with the transition to farming in Britain. The interpretation of this site is therefore key to understanding how agriculture began. Using isotope analysis we show that although the human skeletal collections attributed to Coldrum do contain some of the earliest dated Neolithic human remains in Britain, they also contain the remains of individuals of fifth to seventh centuries AD date. We evaluate subsistence and mobility patterns of early Neolithic populations and provide new information about the origins of those individuals in the collection that date to the fifth to seventh centuries AD. We demonstrate the utility of employing isotope analysis to provide direct and independent information about the provenance of human remains in museum collections.

Sidon on the breadth of the wild sea: Movement and diet on the Mediterranean coast in the Middle Bronze Age

OBJECTIVES

Excavations at Sidon (Lebanon) have revealed dual identities during the Middle Bronze Age (ca. 2000-1600 BCE): a maritime port and center for local distribution, as well as a settlement with a heavy subsistence dependence on the extensive inland hinterlands. We aim to investigate residential mobility at Sidon using isotopic analyses of 112 individuals from 83 burials (20 females, 26 males, and 37 subadults). Veneration and remembrance of the dead is evident from funerary offerings in and near the tombs. With marine fish a major component in funerary offerings, we predict major marine reliance in this coastal population.

MATERIALS AND METHODS

New isotopic evidence of paleomobility (87 Sr/86 Sr, δ18 O) and diet (δ13 Ccarbonate ) is the focus of this research. Previous bulk bone collagen δ13 C and δ15 N analysis is strengthened by further sampling, along with δ34 S where collagen yield was sufficient.

RESULTS

The five non-locals identified (8.9% of the 56 analyzed) come from constructed tombs with high-status grave goods except for one, which was heavily disturbed in antiquity. Dietary investigation of the population confirms reliance on terrestrial resources with no significant marine input. No significant differences in diet between the sexes or burial types are present.

CONCLUSIONS

Although Sidon was part of a growing Mediterranean network evidenced through artefactual finds, relatively low immigration is evident. While religious feasts venerating the dead may have involved significant piscine components, no appreciable marine input in diet is observed. Fish may have been reserved for the deceased or only consumed on feast days alongside the dead rather than a regular part of the Bronze Age menu.

Identification of a female murder victim found in Burgenland, Austria in 1993

In 1993, the skeletal remains of a female corpse were found in Burgenland, Austria. Initial identification of the approximately 25–35-year-old female appeared impossible, but the case was reopened 23 years later. By applying biogeochemical isotope methods to her body tissues, the geographical origin of the unknown corpse could be predicted. The results of the C, N, S, H, Sr, and Pb isotope analyses suggested that the female did not originate from Europe and most likely spent her youth in the northern Caribbean. Using these findings, the police were able to identify the woman within 2 weeks. The female came from the Dominican Republic and resided in Austria for only a short period before she was murdered. This case shows that isotope biogeochemistry investigations can provide the police with crucial information that enables unknown persons to be identified.

Keypoints

C-N-S-H and Sr-Pb isotope analyses were applied to human remains associated with a cold case.

It was possible to determine the region of origin of the unknown deceased individual as the northern Caribbean.

After 23 years, the murder victim was successfully identified.

MASS SPECTROMETRY-BASED TECHNIQUES FOR DIRECT QUANTIFICATION OF HIGH IONIZATION ENERGY ELEMENTS IN SOLID MATERIALS-CHALLENGES AND PERSPECTIVES

The determination of nonmetals, first of all, the most electronegative ones-nitrogen, oxygen, fluorine, chlorine, and bromine, poses the highest challenge for element analysis. These elements are characterized by high reactivity, volatility, high ionization energy, and the absence of intensive spectral lines in the optical spectral range. Conventional techniques of their quantification include considerable "wet chemistry" stages so the application of these techniques for the solid sample is highly laborious and prone to uncontrollable uncertainties. Additionally, current development in material science and other areas requires the quantification of the elements at lower levels with good sensitivity. Owing to their robustness and flexibility, mass spectrometry techniques provide vast possibilities for the quantification, spatial and isotopic analysis, including the solutions for direct analysis of solids. The current review focuses on the application of major mass spectrometric techniques for the quantification of N, O, F, Cl, and Br in solid samples. The following techniques are mainly considered: thermal ionization mass spectrometry (TIMS), isotope-ratio MS (IRMS), secondary ion MS (SIMS), inductively coupled plasma MS (ICP-MS), and glow discharge MS (GDMS); as the most accessible and widely applied for the purpose. General ionization issues, advantages, limitations, and novel methodological solutions are discussed. © 2020 John Wiley & Sons Ltd.

Diversity aboard a Tudor warship: investigating the origins of the Mary Rose crew using multi-isotope analysis

The great Tudor warship, the Mary Rose, which sank tragically in the Solent in 1545 AD, presents a rare archaeological opportunity to research individuals for whom the precise timing and nature of death are known. A long-standing question surrounds the composition of the Tudor navy and whether the crew were largely British or had more diverse origins. This study takes a multi-isotope approach, combining strontium (⁸⁷Sr/⁸⁶Sr), oxygen (δ¹⁸O), sulfur (δ³⁴S), carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope analysis of dental samples to reconstruct the childhood diet and origins of eight of the Mary Rose crew. Forensic ancestry estimation was also employed on a subsample. Provenancing isotope data tentatively suggests as many as three of the crew may have originated from warmer, more southerly climates than Britain. Five have isotope values indicative of childhoods spent in western Britain, one of which had cranial morphology suggestive of African ancestry. The general trend of relatively high δ¹⁵N and low δ¹³C values suggests a broadly comparable diet to contemporaneous British and European communities. This multi-isotope approach and the nature of the archaeological context has allowed the reconstruction of the biographies of eight Tudor individuals to a higher resolution than is usually possible.

Strontium isotope ratios related to childhood mobility: Revisiting sampling strategies of the calcined human pars petrosa ossis temporalis

RATIONALE

Strontium isotope analysis can be applied to the calcined human otic capsule in the petrous part (pars petrosa ossis temporalis; PP) to gain information on childhood mobility in archaeological and forensic contexts. However, only a thin layer of the otic capsule, the inner cortex, demonstrates virtually no remodelling. This paper proposes an improved sampling method for the accurate sampling of the inner cortex of the otic capsule to ensure that ⁸⁷ Sr/⁸⁶ Sr ratios related to early childhood are obtained.

METHODS

Calcined rib and diaphyseal fragments and PP from ten cremation deposits are sampled for strontium isotope analysis, whereby our improved sampling strategy is applied to sample the inner cortex of the otic capsule. This allows inter- and intraskeletal ⁸⁷ Sr/⁸⁶ Sr comparison within an Iron Age collection from Oss, The Netherlands.

RESULTS

Forty percent (4/10) of the calcined PP that were evaluated for this study show marked differences in ⁸⁷ Sr/⁸⁶ Sr (0.00035-0.00065) between the inner cortex and the bone sample surrounding this layer, the external cortex that has higher remodelling rates. Differences in ⁸⁷ Sr/⁸⁶ Sr between various skeletal elements also aided in the identification of the minimum number of individuals.

CONCLUSIONS

Our study demonstrates the problematic nature of the external cortex and stresses the need for a precise sampling method of the correct areas of the otic capsule. This can only be obtained by cutting the calcined PP midmodiolarly to enable adequate combustion degree assessment, and the correct identification and sampling of the inner cortex of the otic capsule.

Spatial patterns in 87Sr/86Sr ratios in modern human dental enamel and tap water from the Netherlands: Implications for forensic provenancing

The analysis of strontium isotope ratios in human dental enamel has become important in the fields of archaeological and forensic science for determining provenance and hence mobility. The prerequisite for the approach relies on a correlation between dietary Sr intake and the underlying local geology. This premise is brought into question for anthropological forensic investigations by the increasing globalisation of food supply, the establishment of nation-wide or international supermarket chains, and increasing urbanisation. To better understand the processes that cause spatial variation of Sr isotope ratios in the modern environment, this study determines the range of ⁸⁷Sr/⁸⁶Sr ratios in the modern Dutch environment based on 296 modern human dental enamel and tap water samples. Tap water ⁸⁷Sr/⁸⁶Sr from the Netherlands range from 0.70837 to 0.71278 (ΔSr_max-min = 0.0044) and modern human enamel from 0.70847 to 0.70995 (ΔSr_max-min = 0.0015). The ⁸⁷Sr/⁸⁶Sr ratios of tap water are predominantly determined by the underlying bedrock geology at the sampling point. In contrast, the human enamel data record an insignificant, weak correlation with water supply or local geology. Hence, the main principle behind the application of ⁸⁷Sr/⁸⁶Sr as a proxy for mobility appears invalid in the modern globalised Dutch context. The range of ⁸⁷Sr/⁸⁶Sr in modern Dutch humans that can be used for anthropological forensic investigations is between 0.7085 and 0.7100 (n = 153), with 98.0% of individuals between 0.7088 and 0.7099.

Strontium, oxygen, and carbon isotope variation in modern human dental enamel

OBJECTIVES

Isotopic analyses using human dental enamel provide information on the mobility and diet of individuals in forensic and archeological studies. Thus far, no study has systematically examined intraindividual coupled strontium (Sr), oxygen (O), and carbon (C) isotope variation in human enamel or the effect that caries have on the isotopic integrity of the enamel. The inadequate quantification of isotopic variation affects interpretations and may constrain sample selection of elements affected by caries. This study aims to quantify the intraindividual isotopic variation and provides recommendations for enamel sampling methods.

MATERIAL AND METHODS

This study presents the first systematic results on intraindividual variation in Sr-O-C isotope composition and Sr concentration in modern human dental enamel of third molars (affected and unaffected by caries). A multiloci sampling approach (n = 6-20) was used to analyze surface and inner enamel, employing thermal ionization mass spectrometry (TIMS) and isotope ratio mass spectrometry (IRMS). Third molars were analyzed from 47 individuals from the Netherlands, Iceland, the United States, the Caribbean, Colombia, Somalia, and South Africa.

RESULTS

Intradental isotopic variation in modern Dutch dental elements was recorded for Sr, O, and C and exceeded the variation introduced by the analytical error. Single loci and bulk sampling approaches of third molars established that a single analysis is only representative of the bulk Sr isotope composition in 60% of the elements analyzed. Dental elements affected by caries showed twice the variation seen in unaffected dental elements. Caries did not consistently incorporate the isotopic composition of the geographical environment in which they developed.

DISCUSSION

The isotopic variability recorded in unaffected inner enamel indicates that variations greater than 0.000200 for ⁸⁷ Sr/⁸⁶ Sr and larger than 2‰ for δ¹⁸ O and δ¹³ C are required to demonstrate changes in modern Dutch human diet or geographic location.