In peat research, the question often arises as to how similar/different the records of cores collected in the same mire are. This has been addressed for some metals (e.g., Pb and Hg), but the question remains open for the molecular composition of organic matter (pOM). Here, we explore this issue by analysing two cores from a raised bog, combining FTIR-ATR, mid-infrared (MIR) indices, and principal component analysis (PCA), and support the interpretation with multilinear regression (MLR) modelling of peat physical (colour) and elemental (C, N, and C/N) properties. The MIR indices and principal components showed depth patterns mainly related to long- and short-term peat decomposition, as well as other secondary changes involving some compounds (e.g., lignin). The depth records of the two cores are remarkably similar, indicating they were synchronously affected by the same processes and to almost the same degree. Cellulose crystallinity was the only property that showed differences in intensity. The good-to-excellent fitting of the MLR models supports the usefulness of FTIR-ATR in peat research. Further studies in a larger number of cores, from the same peatland and from different types of peatlands, are needed to better understand the spatio-temporal responses of the pOM and the factors involved.

Several studies have used Fourier Transform Infrared Spectroscopy (FTIR) to assess chemical and structural changes caused by diagenesis in archaeological human bone, whereas other factors such as individual’s biological profile (sex and age) or the type of bone have seldom been considered. In this study transmission FTIR was applied to 51 bone samples from 19 post-Roman individuals of A Lanzada necropolis (NW Spain). Mid-infrared (MIR) indices (IRSF, MMI, C/P, C/C, Am/P, BPI, API, AmI/AmII) were also calculated and principal component analysis (PCA) was used to explore peak ratios and differences across the whole spectrum. PCA components showed correlation to the C/P and Am/P indices, as well as differences in the Amide III absorbance trends versus Amide A, B, I and II. Signals related to soil material (silicates and aliphatic organic matter) were also revealed by the PCA in some samples. No significant differences in bone composition per sex were found, but cranial carbonate content was significantly higher in non-adults than in adults, and ribs presented a higher amide-to-phosphate ratio (Am/P) than femora and crania. Ribs showed the most altered bioapatite, in agreement with a previous study based on the elemental composition of the samples analysed here. Bioapatite alteration may be responsible for the higher amide content relative to phosphate (i.e., preferential preservation of collagen) in ribs. Thus, caution is advisable when using the Am/P index to assess collagen preservation.

This study integrates historical and osteoarcheological approaches to examine childhood in medieval Iberia, offering insights into living conditions, resource management, and welfare of a particularly fragile demographic sector. Infancy and childhood stress is addressed by recording a marker called dental enamel hypoplasia in deciduous and permanent teeth from six Galician osteological collections that account for the majority of skeletal remains in the area. No differences were observed regarding chronological period, but most collections present higher prevalences than other Iberian sites. This fact may be associated with climate, diet, and social factors. The distribution of lesions and the age when they were formed point to a different childhood experience in urban and rural areas. In addition, the analysis of deciduous teeth suggests intense maternal-fetal stress, especially among urban females.

This investigation focuses on getting a further understanding of the wood degradation processes based on results obtained by chemical analysis (combining mid-infrared spectroscopy and analytical pyrolysis) of waterlogged woods recovered from an acidic marsh sediment during an archaeological excavation at the O Areal archaeological site (Vigo, NW Spain). The woods consist of eight oak (Quercus sp.) and two cherry (Prunus sp.) remains that were radiocarbon dated between 6100 and 5990 cal BC. The results indicate clear changes in the wood’s chemical composition related to the degradation of the polysaccharide and lignin compounds. The chemical changes are attributed to various degradation processes, including, (i) hydrolysis of polysaccharides, (ii) partial depolymerization of lignin as well as polysaccharides, and (iii) partial oxidation of the lignin. Furthermore, contrasting the pyrolysis data with mid-infrared results enabled to connect specific mid-infrared signals with depolymerization and oxidation of the lignocellulosic components in the studied waterlogged wood material. Our findings point out that an accurate interpretation of waterlogged wood chemical degradation requires considerations beyond the commonly stated depletion of wood polysaccharide content. Finally, this study demonstrates that integrating FTIR-ATR spectroscopy and analytical pyrolysis provides a comprehensive and detailed analysis of chemical changes during wood degradation. Such an outcome may be crucial for conservators seeking to identify and address the vulnerabilities of waterlogged ancient wood exposed to specific burial conditions like highly acidic environments.

Here, we present a multimethodological approach of a doctoral research, as a previous step for obtaining and analyzing data. Studies devoted to non-adult individuals from the past have been consolidated in Biological Anthropology and Archeology during the last two decades. Both disciplines study skeletal remains as direct evidence of their existence. In addition to their importance in society, they are very susceptible to environmental and historical/cultural changes. The aim of this PhD project is to delve into the living conditions (health, diet, and growth) of non-adult individuals from medieval communities in the Iberian Peninsula, studying the skeletal remains, with the ultimate goal of, whenever possible, approaching the infants and children social identity on these communities. As case study we propose a sample made up of 7 necropolises from two areas of the Iberian Peninsula: Northwest (Adro Vello, Santa María, San Bartolomé and A Capela do Pilar) and Central (Cadalso de los Vidrios, Uceda and Arroyo Lagunillas) Spain, with a total of 432 individuals, of all ages, non-adults and adults, with a chronological range from the 10th to the 15th centuries. Adult individuals ("surviving children") are included in order to offer a more contextualized and complete view of childhood in these communities. The study phases we intend to develop are: 1) health/ stress: study of porotic lesions; 2) diet: reconstruction through multi-isotopic analyses; 3) growth: metric studies and spectroscopic characterization. The data obtained will be interpreted within the theoretical framework of the Archaeology of Infancy and Childhood.

Human feeding patterns have been reconstructed in Archaeology by analysing either oral pathology or stable isotope ratios in human skeletal remains. However, no clear agreement has been developed between these two methodologies. The main objective of this study is to determine if we can establish a link between them when analysing a population with a hyper-specialized diet, in this case marine resources (and millet/maize). To reach this goal we developed a conjoined multi-isotope analysis using collagen and bioapatite (δ13Ccol, δ15Ncol and δ13Ccar) and a detailed study of oral health (caries, antemortem loss, periapical lesions, periodontal disease, calculus, and wear). All available skeletons with at least one preserved tooth from two cemeteries of the medieval town of Pontevedra (n = 34) were studied. The buried individuals belonged to the guild of fishers and artisans, professions which were dominant among the families of medieval Pontevedra. A detailed FTIR-ATR study of extracted bone bioapatite showed a high correlation between bioapatite carbonate content, carbonate typical vibrations, and FTIR-ATR indices related to bone diagenesis, which is in line with previous research. No significant correlations were found with bioapatite yield and isotopic composition (δ13Ccar and Δ13C), ruling out possible diagenetic effects. The diet was based on marine fish protein with contributions of millets (e.g., δ13Ccar -11.9 ± 1.8‰) that seems to be slightly higher in individuals linked to artisanal guilds. The oral pathology study shows severe dental wear from an early age (Grade 2–4 in permanent dentition for 20% of infants and 60% of juveniles in M1), as well as moderate-high presence of caries in permanent dentition (64%, 22/34) and dental calculus (72%, 24/33). Both the oral pathology and the isotopic signal differ from that observed in other areas of the Iberian Peninsula. This study points to the existence of connections between findings of the two methodologies, and specifically an association between intense dental wear and high consumption of marine resources and millet. At the same time, this analysis implies the necessity of caution in estimation of age by dental wear in populations linked to the sea. 

Late Roman times imprinted with instability, and a consequent decline in large urban centres. In contrast, urbanization seems to have increased in Augusta Emerita (today Mérida), capital of Lusitania, because of the attractive commercial position of this powerful Christian centre. A mixed of beliefs, cultural and social backgrounds was coexisting at the core. These facts could have conditioned diet, perhaps becoming different from the surrounding rural areas, or increasing heterogeneity inside the capital. We reconstructed the diet of the largest Late Roman necropolis of Mérida, the Ampliación del MNAR (3rd -5th centuries AD), whose burial rites have been classified as no-Christian. A total of 70 humans (29 males, 14 females, 23 non-adults) were analysed for δ13Ccol and δ15Ncol to compare their isotopic values in bone with those of 14 animals: 6 sheep/goat, 5 cattle, 2 pigs and 1 horse. Faunal and human isotopic results indicate a trophic chain based on C3 plants. Humans over 12 years old (δ13C=19.2 ± 0.8‰, δ15N = 10.2 ± 1.3‰) seem to have had lower consumption of animal protein and C4 plants than other populations from rural sites, although general diet was rather homogeneous in Hispania. Three outliers, one with important intake of C4 plants, have been identified. Medium animal protein diet reconstructed by stable isotopes and relatively low presence of pathological markers, contrast with high infant mortality, suggesting minor stress in early life. If confirmed, limited diet might be linked to the marginal situation of pagan people in a well christianised Augusta Emerita, but much likely being a consequence of the decline of urban centres during Late Roman times.

The article explores the archaeological site of Santa Coloma d'Ager in northeastern Iberia, active from the 5th to the 11th century AD. Initially, the site featured a church and accompanying cemetery for Christian burials. Archaeological excavations have revealed various burial structures, such as sarcophagi, cyst graves, and slab graves, indicating consistent Christian burial practices despite the region's eventual incorporation into Muslim Al-Andalus. The study incorporates anthropological, paleopathological, and dietary analyses of 107 skeletons, suggesting no unusual mortality patterns or evidence of interpersonal violence. Physiological stress markers indicate some nutritional hardships, aligning with regional agricultural practices. Isotopic analyses reveal a reliance on C3 plant diets and limited animal protein, reflecting the community's rural lifestyle. Overall, the findings illustrate the resilience and continuity of the Mozarab community throughout significant historical upheavals until the 11th century, when the necropolis ceased functioning after the Christian conquest.

Lagore, Co. Meath, has long been a type-site for artificial lake dwellings known as crannogs since excavation in the 1930s by the Harvard Expedition. Renowned for rich finds and documented as the seat of the kings of Southern Brega (8th and 10th centuries AD), alongside the high-status and royal functions of the site, it is now widely recognised that Lagore had a long history of activity stretching back into later prehistory with evidence of deposition of human and animal remains, and metalwork of the Bronze and Iron Ages, and early medieval period. Nonetheless, a poor stratigraphic and archival record has engendered much debate about the timings and tempos of its origins, and the longer-term settlement history of the lough. This paper utilises multi-proxy analysis (Palynology, Geochemistry, Loss-on-Ignition (LOI), Colour, Fourier-transform-infrared-spectroscopy (FTIR) and Attenuated-total-reflectance (ATR)) to provide a deeper chronological understanding of land-use and occupation at Lagore. The most significant findings include the likelihood of local settlement (strong farming and parasite signals) well before the main phases of crannog construction, from at least ∼470 BC; a significant lull in population during the early-mid 5th century AD; a gradual economic recovery from ∼AD 555–620, which coincides with the main phase of crannog construction (based on geochemical and other lithological results); and a slightly later transition into a Royal residence from AD 620, marked by both intensification and diversification of agriculture (wheat/oats, rye, flax and cannabis) and a potential ironworking signal.

During the Middle Ages, the Islamic-ruled area of Iberia was known as Al-Andalus. Present day Catalonia (NE Iberia) included one of the stable borders of Al-Andalus, the Upper Frontier, where Christian and Muslim communities lived together, bringing us the perfect opportunity to address lifestyle changes in form of diet modifications during this period. Human skeletons found in Balaguer (n = 13), an urban Islamic necropolis, and Santa Coloma d’Àger (SCA, n = 16), a rural Christian necropolis under Islamic rule (Mozarabs), are studied for isotopic composition of bone collagen together with three animal samples in order to reconstruct diet (δ13Ccol δ15N), and preliminarily address mobility (δ34S). No differences regarding sex or age have been found. δ13Ccol suggests a diet mainly based on C3 plants food chain. Significative differences between both sites regarding δ15N seem to indicate a preferential access to meat, eggs and/or dairy in the studied individuals from Balaguer in contrast to SCA. Despite their geographical proximity, the humans from Balaguer, tend to show slightly higher δ34S values than those from SCA. The homogeneity observed intra-site suggests that the individuals were local, but Balaguer could be more connected to the sea due to consumption of food imported from the coast, or transhumant animals; a fact that is coherent with the higher δ34S in the two analysed caprines found in Balaguer. However, more analyses are needed to address mobility. The comparison of dietary proxies with other Christian and Islamic sites reveals that the rural/urban character of the site was probably more key in dietary preferences than the predominant religion; in this sense urban communities seem to present a higher access to animal protein than rural sites. Despite being under Islamic rule, the Christian community of SCA has similar isotopic values than other Christian rural sites, a fact that does not support any kind of marginalisation on the former.