A mid-third millennium BC collective burial cave in central Iberia: El Rebollosillo (Torrelaguna, Madrid)

El Rebollosillo es una pequeña cueva kárstica situada en el centro de la Península Ibérica utilizada para la disposición de enterramientos secundarios en la mitad del III milenio AC. Presentamos resultados bioantropológicos, isotópicos (87Sr/86Sr, δ13C y δ18O) y 16 dataciones radiocarbónicas de los restos humanos, una descripción cuantificada de los 43 fragmentos cerámicos y de caracterización mineralógica de 6 cuentas recuperadas durante la excavación de 1989, cuatro de las cuales probablemente proceden de Palazuelo de las Cuevas (Zamora). El análisis bioantropológico indica un mínimo de 21 individuos con todos los rangos de edad y sexo. Se han detectado bajos porcentajes de patologías, mayoritariamente cálculo dental y caries, con casos puntuales de cribra orbitalia, periostosis y artrosis. La disposición de los restos sugiere que sólo los adultos recibieron un tratamiento claramente individualizado, quizás acorde con un estatus adquirido con la edad. Proponemos que el registro representa la última fase de un programa mortuorio cuyas etapas previas debieron desarrollarse en otros lugares y valoramos estos resultados en el contexto del registro funerario regional.El Rebollosillo is a small karstic cave located in the center of Iberia used for the disposition of secondary burials during the mid third millennium BC. We present bioanthropological, isotopic (87Sr/86Sr, δ 13C y δ 18O) analyses and 16 radiocarbon dates on human remains, as well as mineralogical characterization of 6 beads (4 of them variscite from Palazuelo de las Cuevas, Zamora), and a quantitative analysis of 43 pottery fragments recovered during the 1989 excavations. A minimum of 21 individu-als have been identified, covering all age ranges and sex. Low percentages of pathologies have been detected, mainly dental calculus and caries, with specific cases of cribra orbitalia, periostosis and arthritis. Only adults received a clearly individualized treatment, suggestive of achieved status. We interpret the evidence as a multi-staged mortuary program, the last phase of which is documented at the site, with previous stages perhaps carried out elsewhere, and we evaluate these results in the context of the regional funerary record

A mid-third millennium BC collective burial cave in central iberia: El Rebollosillo (Torrelaguna, Madrid)

[EN] El Rebollosillo is a small karstic cave located in the center of Iberia used for the disposition of secondary burials during the mid third millennium BC. We present bioanthropological, isotopic (87Sr/86Sr, δ 13C y δ 18O) analyses and 16 radiocarbon dates on human remains, as well as mineralogical characterization of 6 beads (4 of them variscite from Palazuelo de las Cuevas, Zamora), and a quantitative analysis of 43 pottery fragments recovered during the 1989 excavations. A minimum of 21 individuals have been identified, covering all age ranges and sex. Low percentages of pathologies have been detected, mainly dental calculus and caries, with specific cases of cribra orbitalia, periostosis and arthritis. Only adults received a clearly individualized treatment, suggestive of achieved status. We interpret the evidence as a multi-staged mortuary program, the last phase of which is documented at the site, with previous stages perhaps carried out elsewhere, and we evaluate these results in the context of the regional funerary record.[ES] El Rebollosillo es una pequeña cueva kárstica situada en el centro de la Península Ibérica utilizada para la disposición de enterramientos secundarios en la mitad del III milenio AC. Presentamos resultados bioantropológicos, isotópicos (87Sr/86Sr, δ13C y δ18O) y 16 dataciones radiocarbónicas de los restos humanos, una descripción cuantificada de los 43 fragmentos cerámicos y de caracterización mineralógica de 6 cuentas recuperadas durante la excavación de 1989, cuatro de las cuales probablemente proceden de Palazuelo de las Cuevas (Zamora). El análisis bioantropológico indica un mínimo de 21 individuos con todos los rangos de edad y sexo. Se han detectado bajos porcentajes de patologías, mayoritariamente cálculo dental y caries, con casos puntuales de cribra orbitalia, periostosis y artrosis. La disposición de los restos sugiere que sólo los adultos recibieron un tratamiento claramente individualizado, quizás acorde con un estatus adquirido con la edad. Proponemos que el registro representa la última fase de un programa mortuorio cuyas etapas previas debieron desarrollarse en otros lugares y valoramos estos resultados en el contexto del registro funerario regional.Peer Reviewe

The biota of the Upper Cretaceous site of Lo Hueco (Cuenca, Spain)

The Late Cretaceous (Campanian-Maastrichtian) fossil site of Lo Hueco was recently discovered close to the village of Fuentes (Cuenca, Spain) during the cutting of a little hill for installation of the railway of the Madrid-Levante high-speed train. To date, it has yielded a rich collection of well-preserved Cretaceous macrofossils, including plants, invertebrates, and vertebrates. The recovered fossil assemblage is mainly composed of plants, molluscs (bivalves and gastropods), actinopterygians and teleosteans fishes, amphibians, panpleurodiran (bothremydids) and pancryptodiran turtles, squamate lizards, eusuchian crocodyliforms, rhabdodontid ornithopods, theropods (mainly dromaeosaurids), and titanosaur sauropods. This assemblage was deposited in a near-coast continental muddy floodplain crossed by distributary sandy channels, exposed intermittently to brackish or marine and freshwater flooding as well as to partial or total desiccation events.The Konzentrat-Lagerstatt of Lo Hueco constitutes a singular accumulation of fossils representing individuals of some particular lineages of continental tetrapods, especially titanosaurs, eusuchians and bothremydid turtles. In the case of the titanosaurs, the site has yielded multiple partial skeletons in anatomical connection or with a low dispersion of their skeletal elements. A combination of new taxa, new records of taxa previously known in the Iberian Peninsula, and relatively common taxa in the European record compose the Lo Hueco biota. The particular conditions of the fossil site of Lo Hueco and the preliminary results indicate that the analysis of the geological context, the floral and faunal content, and the taphonomical features of the site provide elements that will be especially useful for reassess the evolutionary history of some lineages of European Late Cretaceous reptiles.Peer reviewe

Seasonality and Paleoecology of the Late Cretaceous Multi-Taxa Vertebrate Assemblage of “Lo Hueco” (Central Eastern Spain)

Isotopic studies of multi-taxa terrestrial vertebrate assemblages allow determination of paleoclimatic and paleoecological aspects on account of the different information supplied by each taxon. The late Campanian-early Maastrichtian “Lo Hueco” Fossil-Lagerstätte (central eastern Spain), located at a subtropical paleolatitude of ~31°N, constitutes an ideal setting to carry out this task due to its abundant and diverse vertebrate assemblage. Local δ18OPO4 values estimated from δ18OPO4 values of theropods, sauropods, crocodyliforms, and turtles are close to δ18OH2O values observed at modern subtropical latitudes. Theropod δ18OH2O values are lower than those shown by crocodyliforms and turtles, indicating that terrestrial endothermic taxa record δ18OH2O values throughout the year, whereas semiaquatic ectothermic taxa δ18OH2O values represent local meteoric waters over a shorter time period when conditions are favorable for bioapatite synthesis (warm season). Temperatures calculated by combining theropod, crocodyliform, and turtle δ18OH2O values and gar δ18OPO4 have enabled us to estimate seasonal variability as the difference between mean annual temperature (MAT, yielded by theropods) and temperature of the warmest months (TWMs, provided by crocodyliforms and turtles). ΔTWMs-MAT value does not point to a significantly different seasonal thermal variability when compared to modern coastal subtropical meteorological stations and Late Cretaceous rudists from eastern Tethys. Bioapatite and bulk organic matter δ13C values point to a C3 environment in the “Lo Hueco” area. The estimated fractionation between sauropod enamel and diet is ~15‰. While waiting for paleoecological information yielded by the ongoing morphological study of the “Lo Hueco” crocodyliforms, δ13C and δ18OCO3 results point to incorporation of food items with brackish influence, but preferential ingestion of freshwater. “Lo Hueco” turtles showed the lowest δ13C and δ18OCO3 values of the vertebrate assemblage, likely indicating a diet based on a mixture of aquatic and terrestrial C3 vegetation and/or invertebrates and ingestion of freshwater.Peer reviewe

Estimating the Ontogenetic Status of an Enantiornithine Bird from the Lower Barremian of El Montsec, Central Pyrenees, Spain.

An Enantiornithes specimen from El Montsec was initially described as an immature individual based upon qualitative traits such as its relatively large orbit and overall proportions of the skull and the postcranium. In this study we re-evaluate the precise determination of the ontogenetic stage of this individual, establishing a cross-talk among taphonomic, anatomic, and morphometric data. The exceptional preservation of the specimen has allowed pondering ontogenetic influence versus preservational bias in features like the external patterns of bone surfaces, instead of being aprioristically considered due to taphonomic alterations only. The rough texture of the periosteal bone associated with pores in the distal, proximal and mid-shaft areas of the humeral shaft, indicates a subadult stage when compared with long bones of modern birds. Forelimb proportions of embryo and juvenile Enanthiornithes are equivalent to those of adult individuals of other taxa within this clade, though this is not a reliable criterion for establishing a precise ontogenetic stage. The El Montsec specimen may be attributed a close adulthood, yet only if growth regimes in Enantiornithes are considered equivalent to those in Neornithes birds

Una revisión de algunos antecedentes en el estudio antropológico y paleopatológico de enterramientos singulares

¿Qué papel desempeña el Laboratorio de Poblaciones del Pasado en el proyecto «Migravit-Sepultus»? El Laboratorio de Poblaciones del Pasado (LAPP) es un grupo de investigación de la Facultad de Ciencias, cuya trayectoria es mucho más larga que la que indica su fecha de inscripción formal en el Registro de Grupos de Investigación de la Universidad Autónoma de Madrid (2011). Es en este momento cuando la vinculación laboral con la universidad de sus miembros permitió solicitar dicha inscripción, ..

Reevaluation of ‘endocostal ossifications’ on the Kebara 2 Neanderthal ribs

The Kebara 2 individual (K2), an adult Neanderthal male, was found in the early 1980s during excavation at the Kebara cave on Mount Carmel (Israel) and is dated to around 60 ka (Arensburg, 1989; Bar-Yosef and Vandermeersh, 1991; Valladas et al., 1991). Because the remains are fairly complete and well preserved, this individual has been used as a reference Neanderthal male in studies of biological aspects such as body size and shape, locomotion, obstetrics or bioenergetics (Rak and Arensburg, 1987; Ruff, 1991, 2002; Tague, 1992; Churchill, 2006; Froehle and Churchill, 2009; Kramer and Sylvester, 2009; Weaver and Hublin, 2009; Holliday, 2012).This research was funded by the Ministerio de Economía y Competitividad (project numbers: CGL2015-63648-P, MAT2013-48426-C2-1-R and HAR2016-78036-P) and the Leakey Foundation (Project 29027). D.G.M. was funded by the European Commission's Research Infrastructure Action via the Synthesys Projects (DK-TAF-3494, BE-TAF-5639, DE-TAF-6404 and SE-TAF-6406) and also by the American Museum of Natural History via a collection study grant. D.G.M. thanks Spanish INEM (Instituto Nacional de Empleo) for its funding support via unemployment benefits.Peer Reviewe

External and internal ontogenetic changes in the first rib

[Objectives]: First ribs bear information about thorax morphology and are usually well preserved, compared to other ribs, in bone/fossil samples. Several studies have addressed ontogeny of the first rib by studying changes in bone microanatomy and rib morphology separately, but no studies have combined both approaches to study how internal and external changes covary during ontogeny. The aim of this project is to fill this gap in our knowledge.[Materials and methods]: We applied 3D geometric morphometrics of sliding semilandmarks to 14 first ribs of Homo sapiens to quantify rib curvature and mid‐shaft cross‐section outline. Ontogenetic variation was addressed throughout a principal component analysis (PCA). Additionally, we made histological sections at the mid‐shaft of the same ribs and studied tissue matrix composition and compartmentalization. Finally, we performed partial least squares (PLS) and regression analyses to study covariation between rib morphology and compartmentalization variables.[Results]: PCA shows that first ribs increase their curvature over the course of ontogeny and the rib midshaft becomes less rounded during ontogeny. In addition, the sternal end becomes more medially oriented during ontogeny and the relative head‐tubercle distance becomes longer. Compartmentalization shows a decrease in the area occupied by mineralized tissues and an increase in the area occupied by non‐mineralized tissues over the course of ontogeny, which covaries with mid‐shaft cross‐section shape.[Conclusions]: Our results show detailed variation in rib morphology along with histological changes in bone tissue compartmentalization and, for the first time, the correlation between the two. This could be related to muscle attachments on the 1st rib and also to changes in breathing mode, from diaphragmatic in perinatals to pulmonary in adults, which could also have implications for understanding thorax evolution.This research was supported and performed within projects CGL2015‐63648‐P, MAT2013‐48426‐C2‐1‐R, HAR2016‐78036‐P (Ministerio de Economía y Competitividad) and the Leakey Foundation.Peer Reviewe

Estimating the Ontogenetic Status of an Enantiornithine Bird from the Lower Barremian of El Montsec, Central Pyrenees, Spain.

An Enantiornithes specimen from El Montsec was initially described as an immature individual based upon qualitative traits such as its relatively large orbit and overall proportions of the skull and the postcranium. In this study we re-evaluate the precise determination of the ontogenetic stage of this individual, establishing a cross-talk among taphonomic, anatomic, and morphometric data. The exceptional preservation of the specimen has allowed pondering ontogenetic influence versus preservational bias in features like the external patterns of bone surfaces, instead of being aprioristically considered due to taphonomic alterations only. The rough texture of the periosteal bone associated with pores in the distal, proximal and mid-shaft areas of the humeral shaft, indicates a subadult stage when compared with long bones of modern birds. Forelimb proportions of embryo and juvenile Enanthiornithes are equivalent to those of adult individuals of other taxa within this clade, though this is not a reliable criterion for establishing a precise ontogenetic stage. The El Montsec specimen may be attributed a close adulthood, yet only if growth regimes in Enantiornithes are considered equivalent to those in Neornithes birds

Covariation between mineralized area and shape of the rib cross section in Homo sapiens and Pan troglodytes: implications for the interpretation of Australopithecus africanus Sts-14 ribcage

Ponencia presentada en: 10th Annual Meeting of the European Society for the study of Human Evolution: Virtual Scientific Conference, 24-26 de septiembre 2020Like many other anatomical structures, the ribcage has changed its morphology and configuration throughout primate evolutionary history. Unfortunately, ribs usually appear broken in the fossil record, which challenges the interpretation of their morphology. In this context, it has been observed that the mineralized area of the rib cross section at the midshaft (Min. Ar. Mid.) could be informative not only about the functional differences in the upper and lower thorax, but also could explain potential interspecific biomechanical changes during evolution [1-3]. As these changes may also be associated with the shape of the rib cross section at the midshaft (Sh. Mid.) [2,3], studying the covariation between both parameters could be interesting in order to understand thoracic biomechanical evolution in hominins from a fragmentary fossil record [2]. This issue was assessed through the analysis of the internal rib microstructure via micro-CT of 5 typical ribs of the Australopithecus africanus Sts-14 from the Ditsong National Museum of Natural History (Pretoria, South Africa) and the complete set of ribs of ten modern humans (Homo sapiens) (120 ribs) from the Universidad Autónoma de Madrid (Spain) and ten chimpanzees (Pan troglodytes) (130 ribs) from the American Museum of Natural History (New York, U.S.A.). Once digitized, the cross section at the midshaft of each rib was extracted using the software Amira 5.4.0. The Min. Ar. Mid. was quantified by Fiji software while the Sh. Mid. was measured using 2D geometric morphometrics in Viewbox 4 software. Eventually, the covariation between both parameters was studied by running a linear regression using MorphoJ software. The results show that the Min. Ar. Mid. and the Sh. Mid. covariate in the typical ribs such that ribs with a rounded Sh. Mid. Will have a larger Min. Ar. Mid. than ribs with a mid-laterally flattened Sh. Mid. This relationship can be extrapolated to a comparative analysis where it is observed that mid-laterally flattened Sh. Mid. and low Min. Ar. Mid. is related to H. sapiens typical ribs while rounded Sh. Mid. and large Min. Ar. Mid. is related to P. troglodytes typical ribs even though chimpanzees may also have typical ribs with a human-like pattern. In addition, it can be seen that Sts-14 ribs pattern of covariation is similar to that of P. troglodytes. Nevertheless, the correlation between the Min. Ar. Mid and the Sh. Mid. is not observed in atypical ribs (costal levels 1, 2, 11 and 12, also 13 in P. troglodytes) due to the contrast between their mid-laterally flattened Sh. Mid. and their high Min. Ar. Mid. The pattern of covariation between the Min. Ar. Mid. and the Sh. Mid. in the typical ribs could be a response to the different thoracic biomechanical needs of P. troglodytes and H. sapiens. The non-bipedal posture of P. troglodytes causes the weight of the head, neck and upper trunk to go through the ribs to reach the upper extremities. Furthermore, since their breathing is hypothetically diaphragmatic, it can be said that chimpanzees ribs are subjected to greater mechanical stress than those of H. sapiens due to their bipedal posture and pulmonary respiration [1,2,4]. This makes P. troglodytes ribs need a larger Min. Ar. Mid. to resist the strong muscular activity [1] and a rounded Sh. Mid. to make it structurally possible. The fact that some chimpanzees typical ribs follow a human-like pattern of covariation could be explained by differences in weight or sex in the tested individuals, but further research would be needed about this hypothesis. Even though the correlation between the Min. Ar. Mid and the Sh. Mid. in Sts-14 ribs is associated to that on P. troglodytes, it should be questioned whether inferences can be made from this result about the similarity of their ribcages due to ontogeny since it is proposed that Sts-14 is not fully adult [5]