Publications by authors named "Antonio Rosas"

91 Publications

Comparative anatomy and 3D geometric morphometrics of the El Sidrón atlases (C1).

J Hum Evol 2020 12 1;149:102897. Epub 2020 Nov 1.

Museo Nacional de Ciencias Naturales (CSIC), Department of Paleobiology, Paleoanthropology Group, J.G. Abascal 2, 28006, Madrid, Spain.

The first cervical vertebra (atlas, C1) is an important element of the vertebral column because it connects the cranial base with the cervical column, thus helping to maintain head posture and contributing to neck mobility. However, few atlases are preserved in the fossil record because of the fragility of this vertebra. Consequently, only eight well-preserved atlases from adult Neandertals have been recovered and described. Here, we present nine new atlas remains from the El Sidrón Neandertal site (Asturias, Spain), two of which (SD-1643 and SD-1605/1595) are sufficiently well preserved to allow for a detailed comparative and three-dimensional geometric morphometric analysis. We compared standard linear measurements of SD-1643 and SD-1605/1595 with those of other Neandertal atlases and carried out three-dimensional geometric morphometric analyses to compare size and shape of SD-1643 and SD-1605/1595 with those of 28 Pan (Pan troglodytes and Pan paniscus), a broad comparative sample of 55 anatomically modern humans from African and European populations, and other fossil hominins (Neandertals, Homo antecessor, Paranthropus boisei). The El Sidrón atlas fossils show typical features of the Neandertal atlas morphology, such as caudal projection of the anterior tubercle, gracility of both the posterior tubercle and the tuberosity for the insertion of the transverse ligament, and an anteroposteriorly elongated neural canal. Furthermore, when compared with atlases from the other taxa, Neandertals exhibit species-specific features of atlas morphology including a relatively lower lateral mass height, relatively narrower transverse foramina, and flatter and more horizontally oriented articular facets. Some of these features fit with previous suggestions of shorter overall length of the cervical spine and potential differences in craniocervical posture and mobility. Our results may support a different spinopelvic alignment in this species, as the atlas morphology suggests reduced cervical lordosis.
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http://dx.doi.org/10.1016/j.jhevol.2020.102897DOI Listing
December 2020

The evolutionary history of Neanderthal and Denisovan Y chromosomes.

Science 2020 09;369(6511):1653-1656

Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany.

Ancient DNA has provided new insights into many aspects of human history. However, we lack comprehensive studies of the Y chromosomes of Denisovans and Neanderthals because the majority of specimens that have been sequenced to sufficient coverage are female. Sequencing Y chromosomes from two Denisovans and three Neanderthals shows that the Y chromosomes of Denisovans split around 700 thousand years ago from a lineage shared by Neanderthals and modern human Y chromosomes, which diverged from each other around 370 thousand years ago. The phylogenetic relationships of archaic and modern human Y chromosomes differ from the population relationships inferred from the autosomal genomes and mirror mitochondrial DNA phylogenies, indicating replacement of both the mitochondrial and Y chromosomal gene pools in late Neanderthals. This replacement is plausible if the low effective population size of Neanderthals resulted in an increased genetic load in Neanderthals relative to modern humans.
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http://dx.doi.org/10.1126/science.abb6460DOI Listing
September 2020

The position of Australopithecus sediba within fossil hominin hand use diversity.

Nat Ecol Evol 2020 07 18;4(7):911-918. Epub 2020 May 18.

Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK.

The human lineage is marked by a transition in hand use, from locomotion towards increasingly dexterous manipulation, concomitant with bipedalism. The forceful precision grips used by modern humans probably evolved in the context of tool manufacture and use, but when and how many times hominin hands became principally manipulative remains unresolved. We analyse metacarpal trabecular and cortical bone, which provide insight into behaviour during an individual's life, to demonstrate previously unrecognized diversity in hominin hand use. The metacarpals of the palm in Australopithecus sediba have trabecular morphology most like orangutans and consistent with locomotor power-grasping with the fingers, while that of the thumb is consistent with human-like manipulation. This internal morphology is the first record of behaviour consistent with a hominin that used its hand for both arboreal locomotion and human-like manipulation. This hand use is distinct from other fossil hominins in this study, including A. afarensis and A. africanus.
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http://dx.doi.org/10.1038/s41559-020-1207-5DOI Listing
July 2020

Toothpicking in early Homo OH 62 from Olduvai Gorge (Tanzania): An indirect evidence of intensive meat consumption?

J Hum Evol 2020 06 1;143:102769. Epub 2020 Apr 1.

Grupo de Paleoantropología, Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (MNCN-CSIC), C/ José Guitérrez Abascal 2, 28006, Madrid, Spain.

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http://dx.doi.org/10.1016/j.jhevol.2020.102769DOI Listing
June 2020

The study of the lower limb entheses in the Neanderthal sample from El Sidrón (Asturias, Spain): How much musculoskeletal variability did Neanderthals accumulate?

J Hum Evol 2020 04 9;141:102746. Epub 2020 Mar 9.

Group of Paleoanthropology MNCN-CSIC, Department of Paleobiology, Museo Nacional de Ciencias Naturales (CSIC), José Gutiérrez Abascal 2, Madrid, Spain.

Entheses have rarely been systematically studied in the field of human evolution. However, the investigation of their morphological variability (e.g., robusticity) could provide new insight into their evolutionary significance in the European Neanderthal populations. The aim of this work is to study the entheses and joint features of the lower limbs of El Sidrón Neanderthals (Spain; 49 ka), using standardized scoring methods developed on modern samples. Paleobiology, growth, and development of both juveniles and adults from El Sidrón are studied and compared with those of Krapina Neanderthals (Croatia, 130 ka) and extant humans. The morphological patterns of the gluteus maximus and vastus intermedius entheses in El Sidrón, Krapina, and modern humans differ from one another. Both Neanderthal groups show a definite enthesis design for the gluteus maximus, with little intrapopulation variability with respect to modern humans, who are characterized by a wider range of morphological variability. The gluteus maximus enthesis in the El Sidrón sample shows the osseous features of fibrous entheses, as in modern humans, whereas the Krapina sample shows the aspects of fibrocartilaginous ones. The morphology and anatomical pattern of this enthesis has already been established during growth in all three human groups. One of two and three of five adult femurs from El Sidrón and from Krapina, respectively, show the imprint of the vastus intermedius, which is absent among juveniles from those Neanderthal samples and in modern samples. The scant intrapopulation and the high interpopulation variability in the two Neanderthal samples is likely due to a long-term history of small, isolated populations with high levels of inbreeding, who also lived in different ecological conditions. The comparison of different anatomical entheseal patterns (fibrous vs. fibrocartilaginous) in the Neanderthals and modern humans provides additional elements in the discussion of their functional and genetic origin.
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http://dx.doi.org/10.1016/j.jhevol.2020.102746DOI Listing
April 2020

Analyses of the neandertal patellae from El Sidrón (Asturias, Spain) with implications for the evolution of body form in Homo.

J Hum Evol 2020 04 5;141:102738. Epub 2020 Mar 5.

Group of Paleoanthropology MNCN-CSIC, Department of Paleobiology, Museo Nacional de Ciencias Naturales (CSIC), José Gutiérrez Abascal 2, Madrid, Spain.

The evolution of the body form in Homo and its potential morphological connection to the arrangement of different skeletal systems is of major interest in human evolution. Patella morphology as part of the knee is potentially influenced by body form. Here, we describe for the first time the patellae remains recovered at El Sidrón Neandertal site and analyze them in a comparative evolutionary framework. We aim to clarify whether morphometric features frequently observed in Neandertal and modern human patellae are retained from a primitive anatomical arrangement or whether they represent derived features (apomorphies). For this purpose, we combine analyses of discrete features, classic anthropological measurements, and 3D geometric morphometrics based on generalized Procrustes analysis, mean size and shape comparisons, and principal components analysis. We found a size increment of the patella in hominin evolution, with large species showing a larger patella. Modern humans and Neandertals exhibit overall larger patellae, with maximum values observed in the latter, likely as a consequence of their broader body shape. Also, some Neandertals display a thicker patella, which has been linked to larger quadriceps muscles. However, Neandertals retain a primitive morphology in their patellar articular surfaces, with similar-sized lateral and medial articular facets, leading to a more symmetrical internal face. This feature is inherited from a primitive Homo ancestor and suggests a different configuration of the knee in Neandertals. Conversely, Homo sapiens exhibits an autoapomorphic patellar anatomy with expanded lateral articular facets. We propose that these distinct configurations of the patella within Homo may be a consequence of different body forms rather than specific functional adaptations of the knee. Thus, the slender body form of modern humans may entail a medial reorientation of the tibial tuberosity (patellar ligament), allowing lateral surface expansion. These anatomical evolutionary variations may involve subtle secondary differences in bipedalism within Homo.
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http://dx.doi.org/10.1016/j.jhevol.2019.102738DOI Listing
April 2020

Relationship between vertical facial pattern and brain structure and shape.

Clin Oral Investig 2020 Apr 7;24(4):1499-1508. Epub 2020 Feb 7.

Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Campus Universitario de Cartuja s/n, 18071, Granada, Spain.

Objectives: Dolichofacial (long-faced) and brachyfacial (short-faced) individuals show specific and well-differentiated craniofacial morphology. Here, we hypothesise that differences in the basicranial orientation and topology between dolicho- and brachyfacial subjects could be associated with differences in the supporting brain tissues.

Material And Methods: Brain volumes (total intracranial, grey matter, and white matter volume), cortical thickness, and the volumes and shapes of fifteen subcortical nuclei were assessed on the basis of magnetic resonance imaging in 185 subjects. Global, voxel-wise and shape analyses, as well as multiple regression models, were generated to evaluate the association between vertical facial variations (dolicho- and brachyfacial spectrum) and brain morphology.

Results: Several differences in brain anatomy between dolicho- and brachyfacial subjects, along with relevant associations between vertical facial indices and brain structure and shape, were found. The most relevant finding of this study is related to the strong association of vertical facial indices with the volumes and shapes of subcortical nuclei, as the dolichofacial pattern increased, the bilateral hippocampus and brain stem expanded, while the left caudate, right pallidus, right amygdala, and right accumbens decreased in volume.

Conclusions: Long- and short-faced human subjects present differences in brain structure and shape.

Clinical Significant: The results of our study increase the clinician's knowledge about brain structure in dolicho- and brachyfacial patients. The findings could be of interest since the affected brain areas are involved in higher cognitive functions in humans, including language, memory, and attention.
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http://dx.doi.org/10.1007/s00784-020-03227-2DOI Listing
April 2020

First continuous pre-Jaramillo to Jaramillo terrestrial vertebrate succession from Europe.

Sci Rep 2020 02 5;10(1):1901. Epub 2020 Feb 5.

IPHES, Institut Català de Paleoecologia Humana i Evolució Social, Zona Educacional 4, Campus Sescelades URV (Edifici W3), 43007, Tarragona, Spain.

In this paper, the early Pleistocene small vertebrate sequence of Quibas-Sima (Quibas karstic complex, Murcia, SE Spain) is presented. The available magnetostratigraphic information together with the small vertebrate association, allow to reliably constrain the age of the different units. The basal unit of the section has recorded a reversed polarity assigned to the pre-Jaramillo Matuyama (C1r.2r, i.e., between 1.2 and 1.07 Ma). The intermediate units have recorded a normal polarity correlated directly with the Jaramillo subchron (C1r.1n, between 1.07 and 0.99 Ma), while the upper units record the post-Jaramillo reverse polarity (C1r.1r, i.e., between 0.99 and 0.78). Jaramillo subchron is especially significant regarding the earliest hominin dispersal in Western Europe. However, vertebrate faunas unambiguously correlatable with Jaramillo subchron are extremely rare in Europe. Thereby, the study of the Quibas-Sima sequence allows to characterize the vertebrate association synchronous to this paleomagnetic episode in southern Iberian Peninsula, and contributes to increase knowledge of the biotic and climatic events that took place in southern Europe at the beginning of the Early-Middle Pleistocene transition, prior to the Matuyama-Brunhes boundary. A continuous small vertebrate succession has been reported, including representatives of the families Bufonidae, Pelodytidae, Testudinidae, Gekkonidae, Blanidae, Lacertidae, Colubridae, Viperidae, Soricidae, Erinaceidae, Rhinolophidae, Vespertilionidae, Muridae, Gliridae, Sciuridae, Leporidae and Ochotonidae The ecological affinities of the faunal association suggest a progressive reduction in forest cover in the onset of the Jaramillo subchron.
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http://dx.doi.org/10.1038/s41598-020-58404-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002404PMC
February 2020

The genomic history of the Iberian Peninsula over the past 8000 years.

Authors:
Iñigo Olalde Swapan Mallick Nick Patterson Nadin Rohland Vanessa Villalba-Mouco Marina Silva Katharina Dulias Ceiridwen J Edwards Francesca Gandini Maria Pala Pedro Soares Manuel Ferrando-Bernal Nicole Adamski Nasreen Broomandkhoshbacht Olivia Cheronet Brendan J Culleton Daniel Fernandes Ann Marie Lawson Matthew Mah Jonas Oppenheimer Kristin Stewardson Zhao Zhang Juan Manuel Jiménez Arenas Isidro Jorge Toro Moyano Domingo C Salazar-García Pere Castanyer Marta Santos Joaquim Tremoleda Marina Lozano Pablo García Borja Javier Fernández-Eraso José Antonio Mujika-Alustiza Cecilio Barroso Francisco J Bermúdez Enrique Viguera Mínguez Josep Burch Neus Coromina David Vivó Artur Cebrià Josep Maria Fullola Oreto García-Puchol Juan Ignacio Morales F Xavier Oms Tona Majó Josep Maria Vergès Antònia Díaz-Carvajal Imma Ollich-Castanyer F Javier López-Cachero Ana Maria Silva Carmen Alonso-Fernández Germán Delibes de Castro Javier Jiménez Echevarría Adolfo Moreno-Márquez Guillermo Pascual Berlanga Pablo Ramos-García José Ramos-Muñoz Eduardo Vijande Vila Gustau Aguilella Arzo Ángel Esparza Arroyo Katina T Lillios Jennifer Mack Javier Velasco-Vázquez Anna Waterman Luis Benítez de Lugo Enrich María Benito Sánchez Bibiana Agustí Ferran Codina Gabriel de Prado Almudena Estalrrich Álvaro Fernández Flores Clive Finlayson Geraldine Finlayson Stewart Finlayson Francisco Giles-Guzmán Antonio Rosas Virginia Barciela González Gabriel García Atiénzar Mauro S Hernández Pérez Armando Llanos Yolanda Carrión Marco Isabel Collado Beneyto David López-Serrano Mario Sanz Tormo António C Valera Concepción Blasco Corina Liesau Patricia Ríos Joan Daura María Jesús de Pedro Michó Agustín A Diez-Castillo Raúl Flores Fernández Joan Francès Farré Rafael Garrido-Pena Victor S Gonçalves Elisa Guerra-Doce Ana Mercedes Herrero-Corral Joaquim Juan-Cabanilles Daniel López-Reyes Sarah B McClure Marta Merino Pérez Arturo Oliver Foix Montserrat Sanz Borràs Ana Catarina Sousa Julio Manuel Vidal Encinas Douglas J Kennett Martin B Richards Kurt Werner Alt Wolfgang Haak Ron Pinhasi Carles Lalueza-Fox David Reich

Science 2019 03;363(6432):1230-1234

Department of Genetics, Harvard Medical School, Boston, MA, USA.

We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula. We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming. We reveal sporadic contacts between Iberia and North Africa by ~2500 BCE and, by ~2000 BCE, the replacement of 40% of Iberia's ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry. We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European-speaking regions but also into non-Indo-European-speaking ones, and we reveal that present-day Basques are best described as a typical Iron Age population without the admixture events that later affected the rest of Iberia. Additionally, we document how, beginning at least in the Roman period, the ancestry of the peninsula was transformed by gene flow from North Africa and the eastern Mediterranean.
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http://dx.doi.org/10.1126/science.aav4040DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6436108PMC
March 2019

Ribcage measurements indicate greater lung capacity in Neanderthals and Lower Pleistocene hominins compared to modern humans.

Commun Biol 2018 16;1:117. Epub 2018 Aug 16.

Paleoanthropology Group, Museo Nacional de Ciencias Naturales (CSIC), José Gutiérrez Abascal 2, 28006, Madrid, Spain.

Our most recent fossil relatives, the Neanderthals, had a large brain and a very heavy body compared to modern humans. This type of body requires high levels of energetic intake. While food (meat and fat consumption) is a source of energy, oxygen via respiration is also necessary for metabolism. We would therefore expect Neanderthals to have large respiratory capacities. Here we estimate the pulmonary capacities of Neanderthals, based on costal measurements and physiological data from a modern human comparative sample. The Kebara 2 male had a lung volume of about 9.04 l; Tabun C1, a female individual, a lung volume of 5.85 l; and a Neanderthal from the El Sidrón site, a lung volume of 9.03 l. These volumes are approximately 20% greater than the corresponding volumes of modern humans of the same body size and sex. These results show that the Neanderthal body was highly sensitive to energy supply.
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http://dx.doi.org/10.1038/s42003-018-0125-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6123625PMC
August 2018

Over 100 years of Krapina: New insights into the Neanderthal thorax from the study of rib cross-sectional morphology.

J Hum Evol 2018 09 6;122:124-132. Epub 2018 Jul 6.

Paleoanthropology Group, Museo Nacional de Ciencias Naturales (CSIC), José Gutiérrez Abascal s/n, 28006 Madrid, Spain.

The Krapina costal sample was studied by Gorjanović-Kramberger in the early twentieth century. He pointed out unique features in the sample such as the rounder rib cross-section, which was recently confirmed in other Neanderthal specimens. Round rib cross-sections are characteristic of Homo ergaster, suggesting this may be plesiomorphic for Pleistocene Homo, but it is unknown whether Homo antecessor also had this rib shape. Furthermore, the influence of allometry on the cross-sectional shape of ribs is still unknown. The large costal sample from Krapina allows us to address these issues. We quantified cross-section morphology at the midshaft throughout a closed curve of one landmark and nine sliding semilandmarks in the Krapina costal remains (n = 7), as well as in other Neanderthals (n = 50), H. antecessor (n = 3) and modern humans, both fossil (n = 12) and recent (n = 160). We used principal components analysis and mean comparisons to explore interspecific differences, regression analysis to investigate allometry, and partial least squares analysis to examine covariation of cross-section shape and overall rib morphology. Neanderthal cross-sections tended to be larger than those of recent humans except for the Krapina and Tabun remains. Regarding shape, inter-group differences were found only in the diaphragmatic thorax, where Neanderthal and H. antecessor ribs were statistically significantly rounder than those of modern humans. Allometry accounted for covariation of size on shape, but the Neandertal and modern human trajectories had different slopes. While our results based on the Krapina costal sample are similar to previous findings, we also make several new insights: 1) the cross-section morphology observed in Neanderthals was probably present in H. antecessor, albeit less marked; 2) the distinct roundness of Neanderthal cross-sections is not related to size; 3) rounder cross-sections are correlated with ribs presenting less curvature in cranial view and a low degree of torsion in recent humans. These results are important for the interpretation of fragmentary Neanderthal costal remains, and the fact that the differences are marked only in the diaphragmatic thorax could have implications for breathing kinematics.
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http://dx.doi.org/10.1016/j.jhevol.2018.05.009DOI Listing
September 2018

Primary visual cortex in neandertals as revealed from the occipital remains from the El Sidrón site, with emphasis on the new SD-2300 specimen.

J Anat 2018 07 6;233(1):33-45. Epub 2018 Apr 6.

Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain.

The comparative analysis of the endocranial surface of the El Sidrón new occipital fragment SD-2300 shows meaningful differences in the configuration of the occipital pole region between neandertals and anatomically modern humans (AMH). The particular asymmetries found in neandertals in the venous sinus drainage and the petalial patterns are recognizable in this new specimen as well. In addition, the supra- and infracalcarine fossae of the occipital pole region appear to deviate obliquely from the mid-line when compared with sapiens. Due to the excellent preservation conditions of SD-2300, the main sulci and gyri of the occipital pole area have been identified, this degree of detail being uncommon in a fossil specimen; in general, the gyrification pattern is similar to AMH, but with some notable differences. Particularly interesting is the description of the lunate and the calcarine sulci. The lunate sulcus is located close to the occipital pole, in a similar posterior position to in other Homo species. Regarding the calcarine sulcus, there are significant differences in the primary visual cortex, with the V1 area, or Brodmann area 17, being larger in Homo neanderthalensis than in Homo sapiens. This may lead to greater visual acuity in neandertals than in sapiens.
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http://dx.doi.org/10.1111/joa.12812DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5987823PMC
July 2018

Response to Comment on "The growth pattern of Neandertals, reconstructed from a juvenile skeleton from El Sidrón (Spain)".

Science 2018 03;359(6380)

Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK.

The comment by DeSilva challenges our suggestion that brain growth of the El Sidrón J1 Neandertal was still incomplete at 7.7 years of age. Evidence suggests that endocranial volume is likely to represent less than 90% adult size at El Sidrón as well as Neandertal male plus Krapina samples, in line with further evidence from endocranial surface histology and dural sinus groove size.
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http://dx.doi.org/10.1126/science.aar3820DOI Listing
March 2018

New Neandertal wrist bones from El Sidrón, Spain (1994-2009).

J Hum Evol 2018 01 31;114:45-75. Epub 2017 Oct 31.

Área de Prehistoria Departamento de Historia, Universidad de Oviedo, Oviedo, Spain.

Twenty-nine carpal bones of Homo neanderthalensis have been recovered from the site of El Sidrón (Asturias, Spain) during excavations between 1994 and 2009, alongside ∼2500 other Neandertal skeletal elements dated to ∼49,000 years ago. All bones of the wrist are represented, including adult scaphoids (n = 6), lunates (n = 2), triquetra (n = 4), pisiforms (n = 2), trapezia (n = 2), trapezoids (n = 5), capitates (n = 5), and hamates (n = 2), as well as one fragmentary and possibly juvenile scaphoid. Several of these carpals appear to belong to the complete right wrist of a single individual. Here we provide qualitative and quantitative morphological descriptions of these carpals, within a comparative context of other European and Near Eastern Neandertals, early and recent Homo sapiens, and other fossil hominins, including Homo antecessor, Homo naledi, and australopiths. Overall, the El Sidrón carpals show characteristics that typically distinguish Neandertals from H. sapiens, such as a relatively flat first metacarpal facet on the trapezium and a more laterally oriented second metacarpal facet on the capitate. However, there are some distinctive features of the El Sidrón carpals compared with most other Neandertals. For example, the tubercle of the trapezium is small with limited projection, while the scaphoid tubercle and hamate hamulus are among the largest seen in other Neandertals. Furthermore, three of the six adult scaphoids show a distinctive os-centrale portion, while another is a bipartite scaphoid with a truncated tubercle. The high frequency of rare carpal morphologies supports other evidence of a close genetic relationship among the Neandertals found at El Sidrón.
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http://dx.doi.org/10.1016/j.jhevol.2017.09.007DOI Listing
January 2018

Right-handed fossil humans.

Evol Anthropol 2017 Nov;26(6):313-324

Department of Anthropology, University of Kansas, Lawrence, KS.

Fossil hominids often processed material held between their upper and lower teeth. Pulling with one hand and cutting with the other, they occasionally left impact cut marks on the lip (labial) surface of their incisors and canines. From these actions, it possible to determine the dominant hand used. The frequency of these oblique striations in an array of fossil hominins documents the typically modern pattern of 9 right- to 1 left-hander. This ratio among living Homo sapiens differs from that among chimpanzees and bonobos and more distant primate relatives. Together, all studies of living people affirm that dominant right-handedness is a uniquely modern human trait. The same pattern extends deep into our past. Thus far, the majority of inferred right-handed fossils come from Europe, but a single maxilla from a Homo habilis, OH-65, shows a predominance of right oblique scratches, thus extending right-handedness into the early Pleistocene of Africa. Other studies show right-handedness in more recent African, Chinese, and Levantine fossils, but the sample compiled for non-European fossil specimens remains small. Fossil specimens from Sima del los Huesos and a variety of European Neandertal sites are predominately right-handed. We argue the 9:1 handedness ratio in Neandertals and the earlier inhabitants of Europe constitutes evidence for a modern pattern of handedness well before the appearance of modern Homo sapiens.
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http://dx.doi.org/10.1002/evan.21554DOI Listing
November 2017

The growth pattern of Neandertals, reconstructed from a juvenile skeleton from El Sidrón (Spain).

Science 2017 09;357(6357):1282-1287

Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.

Ontogenetic studies help us understand the processes of evolutionary change. Previous studies on Neandertals have focused mainly on dental development and inferred an accelerated pace of general growth. We report on a juvenile partial skeleton (El Sidrón J1) preserving cranio-dental and postcranial remains. We used dental histology to estimate the age at death to be 7.7 years. Maturation of most elements fell within the expected range of modern humans at this age. The exceptions were the atlas and mid-thoracic vertebrae, which remained at the 5- to 6-year stage of development. Furthermore, endocranial features suggest that brain growth was not yet completed. The vertebral maturation pattern and extended brain growth most likely reflect Neandertal physiology and ontogenetic energy constraints rather than any fundamental difference in the overall pace of growth in this extinct human.
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http://dx.doi.org/10.1126/science.aan6463DOI Listing
September 2017

The costal remains of the El Sidrón Neanderthal site (Asturias, northern Spain) and their importance for understanding Neanderthal thorax morphology.

J Hum Evol 2017 10 3;111:85-101. Epub 2017 Aug 3.

Paleoanthropology Group, Museo Nacional de Ciencias Naturales (CSIC), J. G. Abascal 2, 28006, Madrid, Spain.

The study of the Neanderthal thorax has attracted the attention of the scientific community for more than a century. It is agreed that Neanderthals have a more capacious thorax than modern humans, but whether this was caused by a medio-lateral or an antero-posterior expansion of the thorax is still debated, and is key to understanding breathing biomechanics and body shape in Neanderthals. The fragile nature of ribs, the metameric structure of the thorax and difficulties in quantifying thorax morphology all contribute to uncertainty regarding precise aspects of Neanderthal thoracic shape. The El Sidrón site has yielded costal remains from the upper to the lower thorax, as well as several proximal rib ends (frequently missing in the Neanderthal record), which help to shed light on Neanderthal thorax shape. We compared the El Sidrón costal elements with ribs from recent modern humans as well as with fossil modern humans and other Neanderthals through traditional morphometric methods and 3D geometric morphometrics, combined with missing data estimation and virtual reconstruction (at the 1st, 5th and 11th costal levels). Our results show that Neanderthals have larger rib heads and articular tubercles than their modern human counterparts. Neanderthal 1st ribs are smaller than in modern humans, whereas 5th and 11th ribs are considerably larger. When we articulated mean ribs (size and shape) with their corresponding vertebral elements, we observed that compared to modern humans the Neanderthal thorax is medio-laterally expanded at every level, especially at T5 and T11. Therefore, in the light of evidence from the El Sidrón costal remains, we hypothesize that the volumetric expansion of the Neanderthal thorax proposed by previous authors would mainly be produced by a medio-lateral expansion of the thorax.
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http://dx.doi.org/10.1016/j.jhevol.2017.06.003DOI Listing
October 2017

Neandertal talus bones from El Sidrón site (Asturias, Spain): A 3D geometric morphometrics analysis.

Am J Phys Anthropol 2017 10 17;164(2):394-415. Epub 2017 Jul 17.

Área de Prehistoria, Department of History, Universidad de Oviedo. Calle Teniente Alfonso Martínez s/n, Oviedo, 33011, Spain.

Objectives: The El Sidrón tali sample is assessed in an evolutionary framework. We aim to explore the relationship between Neandertal talus morphology and body size/shape. We test the hypothesis 1: talar Neandertal traits are influenced by body size, and the hypothesis 2: shape variables independent of body size correspond to inherited primitive features.

Materials And Methods: We quantify 35 landmarks through 3D geometric morphometrics techniques to describe H. neanderthalensis-H. sapiens shape variation, by Mean Shape Comparisons, Principal Component, Phenetic Clusters, Minimum spanning tree analyses and partial least square and regression of talus shape on body variables. Shape variation correlated to body size is compared to Neandertals-Modern Humans (MH) evolutionary shape variation. The Neandertal sample is compared to early hominins.

Results: Neandertal talus presents trochlear hypertrophy, a larger equality of trochlear rims, a shorter neck, a more expanded head, curvature and an anterior location of the medial malleolar facet, an expanded and projected lateral malleolar facet and laterally expanded posterior calcaneal facet compared to MH.

Discussion: The Neandertal talocrural joint morphology is influenced by body size. The other Neandertal talus traits do not co-vary with it or not follow the same co-variation pattern as MH. Besides, the trochlear hypertrophy, the trochlear rims equality and the short neck could be inherited primitive features; the medial malleolar facet morphology could be an inherited primitive feature or a secondarily primitive trait; and the calcaneal posterior facet would be an autapomorphic feature of the Neandertal lineage.
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http://dx.doi.org/10.1002/ajpa.23280DOI Listing
October 2017

Three-dimensional morphometrics of thoracic vertebrae in Neandertals and the fossil evidence from El Sidrón (Asturias, Northern Spain).

J Hum Evol 2017 07 5;108:47-61. Epub 2017 May 5.

Paleoanthropology Group, Museo Nacional de Ciencias Naturales (CSIC), J. G. Abascal 2, 28006, Madrid, Spain.

Well preserved thoracic vertebrae of Neandertals are rare. However, such fossils are important as their three-dimensional (3D) spatial configuration can contribute to the understanding of the size and shape of the thoracic spine and the entire thorax. This is because the vertebral body and transverse processes provide the articulation and attachment sites for the ribs. Dorsal orientation of the transverse processes relative to the vertebral body also rotates the attached ribs in a way that could affect thorax width. Previous research indicates possible evidence for greater dorsal orientation of the transverse processes and small vertebral body heights in Neandertals, but their 3D vertebral structure has not yet been addressed. Here we present 15 new vertebral remains from the El Sidrón Neandertals (Asturias, Northern Spain) and used 3D geometric morphometrics to address the above issues by comparing two particularly well preserved El Sidrón remains (SD-1619, SD-1641) with thoracic vertebrae from other Neandertals and a sample of anatomically modern humans. Centroid sizes of El Sidrón vertebrae are within the human range. Neandertals have larger T1 and probably also T2. The El Sidrón vertebrae are similar in 3D shape to those of other Neandertals, which differ from Homo sapiens particularly in central-lower regions (T6-T10) of the thoracic spine. Differences include more dorsally and cranially oriented transverse processes, less caudally oriented spinous processes, and vertebral bodies that are anteroposteriorly and craniocaudally short. The results fit with current reconstructions of Neandertal thorax morphology.
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http://dx.doi.org/10.1016/j.jhevol.2017.03.008DOI Listing
July 2017

Neandertal and Denisovan DNA from Pleistocene sediments.

Science 2017 May 27;356(6338):605-608. Epub 2017 Apr 27.

Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany.

Although a rich record of Pleistocene human-associated archaeological assemblages exists, the scarcity of hominin fossils often impedes the understanding of which hominins occupied a site. Using targeted enrichment of mitochondrial DNA, we show that cave sediments represent a rich source of ancient mammalian DNA that often includes traces of hominin DNA, even at sites and in layers where no hominin remains have been discovered. By automation-assisted screening of numerous sediment samples, we detected Neandertal DNA in eight archaeological layers from four caves in Eurasia. In Denisova Cave, we retrieved Denisovan DNA in a Middle Pleistocene layer near the bottom of the stratigraphy. Our work opens the possibility of detecting the presence of hominin groups at sites and in areas where no skeletal remains are found.
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http://dx.doi.org/10.1126/science.aam9695DOI Listing
May 2017

Evolutionary anatomy of the Neandertal ulna and radius in the light of the new El Sidrón sample.

J Hum Evol 2017 05 17;106:38-53. Epub 2017 Mar 17.

Group of Paleoanthropology MNCN-CSIC, Department of Paleobiology, Museo Nacional de Ciencias Naturales-CSIC, Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain.

This paper aims to improve our understanding of the phylogenetic trait polarity related to hominin forearm evolution, in particular those traits traditionally defined as "Neandertal features." To this aim, twelve adult and adolescent fragmented forelimb elements (including ulnae and radii) of Homo neanderthalensis recovered from the site of El Sidrón (Asturias, Spain) were examined comparatively using three-dimensional geometric and traditional morphometrics. Mean centroid size and shape comparisons, principal components analysis, and phylogenetic signal analysis were undertaken. Our investigations revealed that the proximal region of the ulna discriminated best between Neandertals and modern humans, with fewer taxonomically-informative features in the distal ulna and radius. Compared to modern humans, the divergent features in the Neandertal ulna are an increase in olecranon breadth (a derived trait), lower coronoid length (primitive), and anterior orientation of the trochlear notch (primitive). In the Neandertal radius, we observe a larger neck length (primitive), medial orientation of the radial tubercle (secondarily primitive), and a curved diaphysis (secondarily primitive). Anatomically, we identified three units of evolutionary change: 1) the olecranon and its fossa, 2) the coronoid-radius neck complex, and 3) the tubercle and radial diaphysis. Based on our data, forearm evolution followed a mosaic pattern in which some features were inherited from a pre-Homo ancestor, others originated in some post-ergaster and pre-antecessor populations, and other characters emerged in the specific Homo sapiens and H. neanderthalensis lineages, sometimes appearing as secondarily primitive. Future investigations might consider the diverse phylogenetic origin of apomorphies while at the same time seeking to elucidate their functional meaning.
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http://dx.doi.org/10.1016/j.jhevol.2017.01.016DOI Listing
May 2017

Dietary reconstruction of the El Sidrón Neandertal familial group (Spain) in the context of other Neandertal and modern hunter-gatherer groups. A molar microwear texture analysis.

J Hum Evol 2017 03 4;104:13-22. Epub 2017 Feb 4.

Paleoanthropology Group MNCN-CSIC, Department of Paleobiology, Museo Nacional de Ciencias Naturales (CSIC), C/ José Gutiérrez Abascal 2, 28006 Madrid, Spain. Electronic address:

Here, we present the analysis of occlusal molar microwear textures of eight individuals from the El Sidrón Neandertal group (Spain). The aims of the study were: 1) to document potential age-, sex-, and maternal lineage-related differences in diet within a Neandertal familial group, and 2) to place the diet of El Sidrón individuals in the context of those of other Neandertal groups. This study also offers an interpretation of the diet of the El Sidrón Neandertals by comparing their microwear signatures to those of recent hunter-gatherer populations with diverse but known diets. The intra-group examination of the microwear signatures are consistent with the females of the El Sidrón group having had more abrasive diets or having used their teeth in more para-masticatory activities than did the males. Aside from the potential sex-related differences in diet, no additional intra-group dietary separation, such as by age group or maternal lineage, was observed. In comparison to other Neandertals, El Sidrón individuals, as a group, have microwear signatures most similar to those of other Neandertals from wooded habitats and different from those that lived in more open habitats. This result is expected based on the available paleoenvironmental reconstructions from El Sidrón Cave. The diet of the El Sidrón Neandertals, just like their Neandertal counterparts from similar wooded habitats, is interpreted as having been mixed, consisting of both meat and vegetable foods.
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http://dx.doi.org/10.1016/j.jhevol.2016.12.003DOI Listing
March 2017

Neanderthal behaviour, diet, and disease inferred from ancient DNA in dental calculus.

Nature 2017 04 8;544(7650):357-361. Epub 2017 Mar 8.

Australian Centre for Ancient DNA, School of Biological Sciences and The Environment Institute, University of Adelaide, Adelaide, South Australia, Australia.

Recent genomic data have revealed multiple interactions between Neanderthals and modern humans, but there is currently little genetic evidence regarding Neanderthal behaviour, diet, or disease. Here we describe the shotgun-sequencing of ancient DNA from five specimens of Neanderthal calcified dental plaque (calculus) and the characterization of regional differences in Neanderthal ecology. At Spy cave, Belgium, Neanderthal diet was heavily meat based and included woolly rhinoceros and wild sheep (mouflon), characteristic of a steppe environment. In contrast, no meat was detected in the diet of Neanderthals from El Sidrón cave, Spain, and dietary components of mushrooms, pine nuts, and moss reflected forest gathering. Differences in diet were also linked to an overall shift in the oral bacterial community (microbiota) and suggested that meat consumption contributed to substantial variation within Neanderthal microbiota. Evidence for self-medication was detected in an El Sidrón Neanderthal with a dental abscess and a chronic gastrointestinal pathogen (Enterocytozoon bieneusi). Metagenomic data from this individual also contained a nearly complete genome of the archaeal commensal Methanobrevibacter oralis (10.2× depth of coverage)-the oldest draft microbial genome generated to date, at around 48,000 years old. DNA preserved within dental calculus represents a notable source of information about the behaviour and health of ancient hominin specimens, as well as a unique system that is useful for the study of long-term microbial evolution.
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http://dx.doi.org/10.1038/nature21674DOI Listing
April 2017

Evidence of toothpick groove formation in Neandertal anterior and posterior teeth.

Am J Phys Anthropol 2017 04 30;162(4):747-756. Epub 2016 Dec 30.

Department of Paleobiology, Paleoanthropology Group, Museo Nacional de Ciencias Naturales (CSIC), Madrid, 28006, Spain.

Objectives: During the microscopic examination of the Neandertal dentitions from El Sidrón (Spain) and Hortus (France), we found unusual fine parallel microstriations on the mesial and distal sides of all tooth types, near the cervix. As its appearance was similar to toothpick grooves described in other Homo species, it could correspond to early stages on its formation. To test this hypothesis we developed an experimental replication of a groove using grass stalks.

Materials And Methods: Comparisons between 204 isolated Neandertal teeth and the two experimental dental specimens corroborate that the marks correspond to initial stages of toothpick groove formation, and we propose a five-grade recording scale that summarized the groove formation process.

Results: Using this new recording procedure, we found that Hortus individuals have higher incidence of this trait (eight individuals out of nine) than the El Sidrón individuals (nine out of 11). Toothpick grooves from El Sidrón show the earliest stages of development, whereas the grooves found on Hortus Neandertals were well-developed. Toothpick grooves were also found in 21 incisors and canines.

Conclusions: These differences could be due to the more advanced occlusal dental wear in Hortus individuals, maybe age-related and with a more meat-based diet maybe favoring the inclusion of food debris and thus probing as the cleaning methodology. Our results allow the identification and characterization of incipient toothpick grooves on the human fossil record and contribute to increase our knowledge on Neandertals behavioral and oral care habits.
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http://dx.doi.org/10.1002/ajpa.23166DOI Listing
April 2017

Adult Neandertal clavicles from the El Sidrón site (Asturias, Spain) in the context of Homo pectoral girdle evolution.

J Hum Evol 2016 06 3;95:55-67. Epub 2016 May 3.

Área de Prehistoria, Department of History, Universidad de Oviedo, Calle Teniente Alfonso Martínez s/n, 33011 Oviedo, Spain.

We undertook a three-dimensional geometric morphometric (3DGM) analysis on 12 new Neandertal clavicle specimens from the El Sidrón site (Spain), dated to 49,000 years ago. The 3DGM methods were applied in a comparative framework in order to improve our understanding of trait polarity in features related to Homo pectoral girdle evolution, using other Neandertals, Homo sapiens, Pan, ATD6-50 (Homo antecessor), and KNM-WT 15000 (Homo ergaster/erectus) in the reference collection. Twenty-nine homologous landmarks were measured for each clavicle. Variation and morphological similarities were assessed through principal component analysis, conducted separately for the complete clavicle and the diaphysis. On average, Neandertal clavicles had significantly larger muscular entheses, double dorsal curvature, clavicle torsion, and cranial orientation of the acromial end than non-Neandertal clavicles; the El Sidrón clavicles fit this pattern. Variation within the samples was large, with extensive overlap between Homo species; only chimpanzee specimens clearly differed from the other specimens in morphometric terms. Taken together, our morphometric analyses are consistent with the following phylogenetic sequence. The primitive condition of the clavicle is manifest in the cranial orientation of both the acromial and sternal ends. The derived condition expressed in the H. sapiens + Neandertal clade is defined by caudal rotation of both the sternal and acromial ends, but with variation in the number of acromia remaining in a certain cranial orientation. Finally, the autapomorphic Neandertal condition is defined by secondarily acquired primitive cranial re-orientation of the acromial end, which varies from individual to individual. These results suggest that the pace of phylogenetic change in the pectoral girdle does not seem to follow that of other postcranial skeletal features.
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http://dx.doi.org/10.1016/j.jhevol.2016.03.005DOI Listing
June 2016

Ancient gene flow from early modern humans into Eastern Neanderthals.

Nature 2016 Feb 17;530(7591):429-33. Epub 2016 Feb 17.

Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany.

It has been shown that Neanderthals contributed genetically to modern humans outside Africa 47,000-65,000 years ago. Here we analyse the genomes of a Neanderthal and a Denisovan from the Altai Mountains in Siberia together with the sequences of chromosome 21 of two Neanderthals from Spain and Croatia. We find that a population that diverged early from other modern humans in Africa contributed genetically to the ancestors of Neanderthals from the Altai Mountains roughly 100,000 years ago. By contrast, we do not detect such a genetic contribution in the Denisovan or the two European Neanderthals. We conclude that in addition to later interbreeding events, the ancestors of Neanderthals from the Altai Mountains and early modern humans met and interbred, possibly in the Near East, many thousands of years earlier than previously thought.
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http://dx.doi.org/10.1038/nature16544DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4933530PMC
February 2016

Cranial base topology and basic trends in the facial evolution of Homo.

J Hum Evol 2016 Feb 14;91:26-35. Epub 2015 Dec 14.

Paleoanthropology Group, Museo Nacional de Ciencias Naturales, CSIC, J. G. Abascal 2, 28006 Madrid, Spain.

Facial prognathism and projection are important characteristics in human evolution but their three-dimensional (3D) architectonic relationships to basicranial morphology are not clear. We used geometric morphometrics and measured 51 3D-landmarks in a comparative sample of modern humans (N = 78) and fossil Pleistocene hominins (N = 10) to investigate the spatial features of covariation between basicranial and facial elements. The study reveals complex morphological integration patterns in craniofacial evolution of Middle and Late Pleistocene hominins. A downwards-orientated cranial base correlates with alveolar maxillary prognathism, relatively larger faces, and relatively larger distances between the anterior cranial base and the frontal bone (projection). This upper facial projection correlates with increased overall relative size of the maxillary alveolar process. Vertical facial height is associated with tall nasal cavities and is accommodated by an elevated anterior cranial base, possibly because of relations between the cribriform and the nasal cavity in relation to body size and energetics. Variation in upper- and mid-facial projection can further be produced by basicranial topology in which the midline base and nasal cavity are shifted anteriorly relative to retracted lateral parts of the base and the face. The zygomatics and the middle cranial fossae act together as bilateral vertical systems that are either projected or retracted relative to the midline facial elements, causing either midfacial flatness or midfacial projection correspondingly. We propose that facial flatness and facial projection reflect classical principles of craniofacial growth counterparts, while facial orientation relative to the basicranium as well as facial proportions reflect the complex interplay of head-body integration in the light of encephalization and body size decrease in Middle to Late Pleistocene hominin evolution. Developmental and evolutionary patterns of integration may only partially overlap morphologically, and traditional concepts taken from research on two-dimensional (2D) lateral X-rays and sections have led to oversimplified and overly mechanistic models of basicranial evolution.
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http://dx.doi.org/10.1016/j.jhevol.2015.11.001DOI Listing
February 2016

Possible Further Evidence of Low Genetic Diversity in the El Sidrón (Asturias, Spain) Neandertal Group: Congenital Clefts of the Atlas.

PLoS One 2015 29;10(9):e0136550. Epub 2015 Sep 29.

Área de Prehistoria, Department of History, Universidad de Oviedo, Oviedo, Spain.

We present here the first cases in Neandertals of congenital clefts of the arch of the atlas. Two atlases from El Sidrón, northern Spain, present respectively a defect of the posterior (frequency in extant modern human populations ranging from 0.73% to 3.84%), and anterior (frequency in extant modern human populations ranging from 0.087% to 0.1%) arch, a condition in most cases not associated with any clinical manifestation. The fact that two out of three observable atlases present a low frequency congenital condition, together with previously reported evidence of retained deciduous mandibular canine in two out of ten dentitions from El Sidrón, supports the previous observation based on genetic evidence that these Neandertals constituted a group with close genetic relations. Some have proposed for humans and other species that the presence of skeletal congenital conditions, although without clinical significance, could be used as a signal of endogamy or inbreeding. In the present case this interpretation would fit the general scenario of high incidence of rare conditions among Pleistocene humans and the specific scenariothat emerges from Neandertal paleogenetics, which points to long-term small and decreasing population size with reduced and isolated groups. Adverse environmental factors affecting early pregnancies would constitute an alternative, non-exclusive, explanation for a high incidence of congenital conditions. Further support or rejection of these interpretations will come from new genetic and skeletal evidence from Neandertal remains.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0136550PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4587856PMC
June 2016

A geometric morphometrics comparative analysis of Neandertal humeri (epiphyses-fused) from the El Sidrón cave site (Asturias, Spain).

J Hum Evol 2015 May 24;82:51-66. Epub 2015 Mar 24.

Área de Prehistoria, Department of History, Universidad de Oviedo, Calle Teniente Alfonso Martínez s/n, 33011 Oviedo, Spain.

A new collection of 49,000 year old Neandertal fossil humeri from the El Sidrón cave site (Asturias, Spain) is presented. A total of 49 humeral remains were recovered, representing 10 left and 8 right humeri from adults, adolescents, and a juvenile (not included in the analyses). 3D geometric morphometric (GM) methods as well as classic anthropological variables were employed to conduct a broad comparative analysis by means of mean centroid size and shape comparisons, principal components analysis, and cluster studies. Due to the fragmentary nature of the fossils, comparisons were organized in independent analyses according to different humeral portions: distal epiphysis, diaphysis, proximal epiphysis, and the complete humerus. From a multivariate viewpoint, 3D-GM analyses revealed major differences among taxonomic groups, supporting the value of the humerus in systematic classification. Notably, the Australopithecus anamensis (KP-271) and Homo ergaster Nariokotome (KNM-WT 15000) distal humerus consistently clusters close to those of modern humans, which may imply a primitive condition for Homo sapiens morphology. Australopithecus specimens show a high degree of dispersion in the morphospace. The El Sidrón sample perfectly fits into the classic Neandertal pattern, previously described as having a relatively wide olecranon fossa, as well as thin lateral and medial distodorsal pillars. These characteristics were also typical of the Sima de los Huesos (Atapuerca) sample, African mid-Pleistocene Bodo specimen, and Lower Pleistocene TD6-Atapuerca remains and may be considered as a derived state. Finally, we hypothesize that most of the features thought to be different between Neandertals and modern humans might be associated with structural differences in the pectoral girdle and shoulder joint.
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http://dx.doi.org/10.1016/j.jhevol.2015.02.018DOI Listing
May 2015

Division of labor by sex and age in Neandertals: an approach through the study of activity-related dental wear.

J Hum Evol 2015 Mar 11;80:51-63. Epub 2015 Feb 11.

Paleoanthropology Group, Department of Paleobiology, Museo Nacional de Ciencias Naturales (MNCN-CSIC), C/ José Gutiérrez Abascal 2, 28006 Madrid, Spain.

The analysis of activity-related dental wear patterns in prehistoric anatomically modern humans and modern hunter-gatherers has shown sex differences attributable to a gendered division of labor. Neandertals are known to have extensive anterior dental wear related to the use of their front teeth as a tool. In this study we analyze the i) cultural striations (scratches on the labial surface of the anterior teeth with a cut-mark morphology), and ii) dental chipping (ante-mortem microfracture involving enamel or both enamel and dentine) in 19 Neandertal individuals from the l'Hortus (France), Spy (Belgium), and El Sidrón (Spain) sites, and compare the characteristics of those traits with the age and sex estimation for the individuals and among samples. The study reveals that all individuals have cultural striations, but those detected on the adult females are longer than the striations found in adult males. Regarding the distribution of dental chipping, the prevalence of this trait is higher in the maxillary dentition of males whereas females have the majority of dental chipping on their mandibular teeth. The differences detected on the overall activity-related dental wear pattern denote a difference or a division of labor by age and sex in Neandertals while using the mouth as a third hand, i.e., in activities other than the provisioning of food, and provide new evidence for the lifestyle of this Pleistocene fossil human species.
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http://dx.doi.org/10.1016/j.jhevol.2014.07.007DOI Listing
March 2015