Olalla López-Costas’s research while affiliated with Stockholm University and other places

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.

Presentamos el planteamiento multimetodológico de una investigación doctoral, previa al análisis y obtención de datos. Desde hace dos décadas los estudios dedicados a los individuos no adultos del pasado se han consolidado en Antropología Biológica y Arqueología. Ambas disciplinas estudian los restos esqueléticos ya que son una evidencia directa de su existencia. Además de su importancia en la sociedad, son sujetos muy susceptibles a los cambios ambientales e históricos/culturales. El objetivo del proyecto doctoral es ahondar en las condiciones de vida (salud, dieta y crecimiento) de los individuos no adultos de comunidades medievales de la Península Ibérica, estudiando los restos esqueléticos, con la finalidad última de, siempre que sea posible, aproximarnos a la identidad social infantil en estas comunidades. Como caso de estudio proponemos una muestra de 7 necrópolis de dos zonas de la Península Ibérica: Noroeste (Adro Vello, Santa María, San Bartolomé y A Capela do Pilar) y Centro (Cadalso de los Vidrios, Uceda y Arroyo Lagunillas) de España; que suman un total de 432 individuos de todas las edades, esqueletos no adultos y adultos, con un rango cronológico del siglo X al XV d.C. Se incluyen individuos adultos (“niños que sobrevivieron”) para ofrecer una visión más contextualizada y completa de la infancia en estas comunidades. Las fases de estudio que se pretende desarrollar son: 1) salud/estrés: estudio de lesiones poróticas; 2) alimentación: reconstrucción de la dieta mediante análisis multi-isotópicos; 3) crecimiento: estudios métricos y caracterización espectroscópica. Los datos obtenidos serán interpretados dentro del marco teórico de la Arqueología de la Infancia. Presentamos una combinación metodológica para ahondar en las condiciones de vida, ambientales y sociales, de no-adultos del Noroeste (4 necrópolis, Galicia) y Centro (3 necrópolis, Madrid, Castilla la Mancha) de Iberia de cronología medieval. Se desarrollan tres fases: 1) salud/estrés: estudio de marcadores inespecíficos de estrés biológico; 2) alimentación: reconstrucción de la dieta mediante análisis multi-isotópicos; 3) crecimiento: basado en métrica y caracterización espectroscópica. Este trabajo pretende presentar un modelo para conocer las identidades de los no-adultos, en base el comportamiento nutricional y las prácticas culturales específicas de la zona y periodo reconstruidas a través de las características físicas/biológicas preservadas en sus esqueletos.

Extracted bioapatite (BAp) from archaeological skeletal remains is used in studies reconstructing diet, mobility, and lifestyle of past human populations. Despite this, few investigations have researched extracted BAp, although some of them suggest that chemical extraction may alter BAp structure and composition. Here, we apply attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy on BAp extracted from archaeological bones: 29 human individuals of two medieval-postmedieval necropolises and 30 non-humans from Roman and medieval times, all from northwestern Spain. Statistical treatment includes principal component analysis (PCA) on (i) selected peaks (dPCA) and (ii) whole spectrum (tPCA). Extracted BAp shows the characteristic vibrations of the main components of a non-stoichiometric apatite, as well as other minor vibrations related to labile components. PCA results are also consistent in revealing the structural and compositional features of BAp, although tPCA results correlate better to BAp IR indices and properties than dPCA results. Significant differences in BAp spectral signal were found between human and non-human bone, collections (i.e., necropolises), human groups (non-adults vs. adults), human bone type (long bones vs. ribs), and non-human groups (bovine vs. ovicaprid). Thus, extracted BAp also retains crucial information that could be related to pre- and postmortem modifications of bone.

Este estudio se centra en un primer análisis paleopatológico de la necrópolis de la Ampliación del Museo Nacional de Arte Romano (MNAR ss. III-VI d.C.) de Mérida, Badajoz. Está compuesta por 118 individuos inhumados y se estima que fueran de media-baja clase social por su contexto funerario. El objetivo principal es relacionar la paleopatología con el contexto arqueológico de la necrópolis. Entre otros, los resultados nos muestran un elevado número de individuos afectados por hipoplasia de esmalte y por traumatismos. Esto nos hace pensar en unas condiciones de vida duras que coincide con el contexto funerario.

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 iron working signal

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.