Dietary strategies of Pleistocene Pongo sp. and Homo erectus on Java (Indonesia)

Understanding intra-individual isotopic variability in modern cremated human remains for forensic and archaeological studies

Cremated bone fragments can be studied using structural, elemental, and isotope analyses in archaeological contexts to reconstruct funerary practices and understand past mobility and migrations of populations that practiced cremation. However, the potential of isotope analyses of cremated bone in forensic contexts remains heavily unexplored. The identification of fire victims can be complex as the remains can be extremely fragmented and commingled. The high temperatures (up to 1000°C and above) destroy most organic matter such that, obtaining reliable DNA from such intensively burned human remains is extremely difficult. Still, other signals present in bone, such as strontium concentrations and isotopes, are preserved during cremation, and could be used to assess the geographical origin of unidentified fire-affected individuals. Carbon and oxygen isotope ratios together with infrared analyses provide information about the burning conditions and could help understanding how a body was burned. Here, isotope and infrared analyses are carried out on fourteen recently deceased cremated individuals of known residential history from the UTK Donated Skeletal Collection curated by the Forensic Anthropology Center (Knoxville, Tennessee). By carrying out these measurements on different bones with different turnover rates (i.e., otic capsule of the petrous part of the temporal bone, femur, and rib), we endeavor to reconstruct life histories of recently deceased cremated individuals and gain new insights into cremation practices. The results highlight differences in carbon and oxygen isotopes between different skeletal elements and confirm their potential to gather information about the way a body was burned (e.g., temperatures, fuel used). Strontium concentrations and isotope ratios were also measured to assess the geographical origin of these individuals. The use of strontium isotope ratios, however, seem to have limitations for individuals born in the last few decades due to globalization of consumed food resources. Nevertheless, it is still possible to obtain information about the birthplace of older individuals (> 50 years) by analyzing strontium isotope ratios in the petrous part of their temporal bone, which retains a signal linked to the first few years of their lives when local resources were still used in larger quantities compared to today.

A short and sickly life. Multi-indicator analysis of an infant from a late antique Italian burial site (Piano della Civita, Artena, 3rd-5th cent CE)

OBJECTIVE

To evaluate pathological lesions and related growth impairment in an infant from a late antiquity context in central Italy.

MATERIALS

The individual labeled as 04.AR.60004 comes from a small burial plot in Piano della Civita di Artena, Italy, dated to the 3rd-5th centuries.

METHODS

Macroscopic examination, metric analysis, dental histomorphometry, amelogenin sequencing, and aDNA analyses were employed.

RESULTS

Individual 04.AR.60004 is an infant male with an estimated age-at-death of 2 months showing two metabolic stress events, one occurring before birth and one a few days before death. The well-preserved skeleton shows diffuse abnormal cortical porosity and subperiosteal new bone formation.

CONCLUSIONS

The type and distribution of the skeletal lesions suggest a diagnosis of infantile scurvy, probably associated with a general status of malnutrition. Dimensions of cranial and postcranial bones show a wide discrepancy between the skeletal age (38-40 fetal weeks) and the dental histological age (2 months).

SIGNIFICANCE

Including enamel histology age-at-death estimation may expand our knowledge of the influence of severe pathological cases on growth.

LIMITATIONS

Although scurvy remains the most obvious diagnosis, we cannot exclude other related micronutrient deficiencies which might have affected the individual.

SUGGESTIONS FOR FURTHER RESEARCH

Including dental histometric and molecular sex estimation in infant pathological cases can help us to recognize impaired growth and enhance our understanding of sex-based susceptibility and potential biases in childcare within ancient communities.

Laser-Induced Breakdown Spectroscopy as an Accurate Forensic Tool for Bone Classification and Individual Reassignment

This article provides a detailed discussion of the evidence available to date on the application of laser-induced breakdown spectroscopy (LIBS) and supervised classification methods for the individual reassignment of commingled bone remains. Specialized bone chemistry studies have demonstrated the suitability of bone elemental composition as a distinct individual identifier. Given the widely documented ability of the LIBS technique to provide elemental emission spectra that are considered elemental fingerprints of the samples analyzed, the analytical potential of this technique has been assessed for the investigation of the contexts of commingled bone remains for their individual reassignment. The LIBS bone analysis consists of the direct ablation of micrometric portions of bone samples, either on their surface or within their internal structure. To produce reliable, accurate, and robust bone classifications, however, the available evidence suggests that LIBS spectral information must be processed by appropriate methods. When comparing the performance of seven different supervised classification methods using spectrochemical LIBS data for individual reassociation, those employing artificial intelligence-based algorithms produce analytically conclusive results, concretely individual reassociations with 100% accuracy, sensitivity, and robustness. Compared to LIBS, other techniques used for the purpose of interest exhibit limited performance in terms of robustness, sensitivity, and accuracy, as well as variations in these results depending on the type of bones used in the classification. The available literature supports the suitability of the LIBS technique for reliable individual reassociation of bone remains in a fast, simple, and cost-effective manner without the need for complicated sample processing.

Australopithecus at Sterkfontein did not consume substantial mammalian meat

Incorporation of animal-based foods into early hominin diets has been hypothesized to be a major catalyst of many important evolutionary events, including brain expansion. However, direct evidence of the onset and evolution of animal resource consumption in hominins remains elusive. The nitrogen-15 to nitrogen-14 ratio of collagen provides trophic information about individuals in modern and geologically recent ecosystems (<200,000 years ago), but diagenetic loss of this organic matter precludes studies of greater age. By contrast, nitrogen in tooth enamel is preserved for millions of years. We report enamel-bound organic nitrogen and carbonate carbon isotope measurements of Sterkfontein Member 4 mammalian fauna, including seven Australopithecus specimens. Our results suggest a variable but plant-based diet (largely C3) for these hominins. Therefore, we argue that Australopithecus at Sterkfontein did not engage in regular mammalian meat consumption.

Enamel histomorphometry, growth patterns and developmental trajectories of the first deciduous molar in an Italian early medieval skeletal series

Understanding the growth patterns and developmental trajectories of teeth during early life stages provides valuable insights into the ontogeny of individuals, particularly in archaeological populations where such information is scarce. This study focuses on first deciduous molars, specifically investigating crown formation times and daily secretion rates, through histological analysis. A total of 34 teeth from the Early Medieval necropolises of Casalmoro and Guidizzolo (Mantua, Lombardy, northern Italy) were analysed assessing growth parameters and identifying possible differences between sites and between sexes, which are determined through proteomic analysis. Furthermore, a robust linear regression model relating prism length and secretion time was built to estimate growth rates also in teeth in which the finest incremental markings are not visible. The daily secretion rates (DSR) in inner enamel showed a high homogeneity between dental arches, sexes and the two sites. Values fall within the known range reported in the literature for the same tooth class in archaeological populations. However, a difference in DSR was observed when compared with modern sample published values. Crown formation times and age at crown completion differ between dental arches, with maxillary first molars initiating their matrix apposition earlier than mandibular molars as formerly reported. However, no significant differences were highlighted in association with sex. This study expands our understanding of the growth and development of the first deciduous molars in a medieval population, providing valuable insights into growth trajectories specific to the dental arch. These findings highlight the need for extensive investigations using similar methodologies to attain more accurate and comprehensive information about the developmental patterns of first deciduous molars. Additionally, proteomic analysis improves the capability to conduct sex-specific histological assessments of immature individuals, thanks to this method's application in determining their sex.

Oxygen isotopes in orangutan teeth reveal recent and ancient climate variation

Studies of climate variation commonly rely on chemical and isotopic changes recorded in sequentially produced growth layers, such as in corals, shells, and tree rings, as well as in accretionary deposits-ice and sediment cores, and speleothems. Oxygen isotopic compositions (δ18O) of tooth enamel are a direct method of reconstructing environmental variation experienced by an individual animal. Here, we utilize long-forming orangutan dentitions (Pongo spp.) to probe recent and ancient rainfall trends on a weekly basis over ~3-11 years per individual. We first demonstrate the lack of any consistent isotopic enrichment effect during exclusive nursing, supporting the use of primate first molar teeth as environmental proxies. Comparisons of δ18O values (n=2016) in twelve molars from six modern Bornean and Sumatran orangutans reveal a high degree of overlap, with more consistent annual and bimodal rainfall patterns in the Sumatran individuals. Comparisons with fossil orangutan δ18O values (n=955 measurements from six molars) reveal similarities between modern and late Pleistocene fossil Sumatran individuals, but differences between modern and late Pleistocene/early Holocene Bornean orangutans. These suggest drier and more open environments with reduced monsoon intensity during this earlier period in northern Borneo, consistent with other Niah Caves studies and long-term speleothem δ18O records in the broader region. This approach can be extended to test hypotheses about the paleoenvironments that early humans encountered in southeast Asia.