Middle Pleistocene hominin teeth from Biache‑Saint‑Vaast, France

The study of dental morphology can be a very useful tool to understand the origin and evolution of Neanderthals in Europe during the Middle Pleistocene (MP). At present, the earliest evidence, ca. 430 ka, of a pre-Neanderthal population in Europe is the hominin sample from Atapuerca-Sima de los Huesos (SH) that present clear dental affinities with Neanderthals while other penecontemporaneous populations, such as Arago or Mala Balanica, exhibit less Neanderthal traits. We present the morphometric study of the external and internal dental structures of eleven hominin dental remains recovered from the MP, ca. 240 ka, French site of Biache-Saint-Vaast (BSV). Our analyses place the BSV hominins within the MP group, together with SH, Fontana Ranuccio, Visogliano, Steinheim or Montmaurin, that showgreater morphological affinities with Neanderthals. Moreover, we identified interpopulation variability in the expression of the enamel thickness trait, with BSV hominins sharing the unique combination of thin and thick pattern in the premolars and molars with the SH population. These results further support the coexistence of two or more populations in Europe during the MP that reflect the population and settlement of human groups suggested by the Central Area of Dispersals of Eurasia (CADE) and sink and source model

Comparing the Boxgrove and Atapuerca (Sima de los Huesos) human fossils: Do they represent distinct paleodemes?

The early Middle Pleistocene human material from Boxgrove (West Sussex, UK) consists of a partial left tibia and two lower incisors from a separate adult individual. These remains derive from deposits assigned to the MIS 13 interglacial at about 480 ka and have been referred to as Homo cf. heidelbergensis. The much larger skeletal sample from the Sima de los Huesos (Atapuerca, Spain) is dated to the succeeding MIS 12, at about 430 ka. This fossil material has previously been assigned to Homo heidelbergensis but is now placed within the Neanderthal clade. Because of the scarcity of human remains from the Middle Pleistocene and their morphological variability, this study assessed whether the Boxgrove specimens fit within the morphological variability of the homogeneous Sima de los Huesos population. Based on morphometric analyses performed against 22 lower incisors from Sima de los Huesos and published material, the data from the Boxgrove incisors place them comfortably within the range of Sima de los Huesos. Both assemblages present robust incisors distinct from the overall small recent Homo sapiens incisors, and Boxgrove also aligns closely with Homo neanderthalensis and some other European Middle Pleistocene hominins. Following morphological and cross-sectional analyses of the Boxgrove tibia compared to seven adult Sima de los Huesos specimens and a set of comparative tibiae, Boxgrove is shown to be similar to Sima de los Huesos and Neanderthals in having thick cortices and bone walls, but in contrast resembles modern humans in having a straight anterior tibial crest and a suggestion of a lateral concavity. Based on the patterns observed, there is no justification for assigning the Boxgrove and Sima de los Huesos incisors to distinct paleodemes, but the tibial data show greater contrasts and suggest that all three of these samples are unlikely to represent the same paleodeme

The first direct ESR dating of a hominin tooth from Atapuerca Gran Dolina TD-6 (Spain) supports the antiquity of Homo antecessor

The present study reports the results of the first direct Electron Spin Resonance (ESR) dating study of Homo antecessor, the oldest known hominin species identified in Western Europe. The analysis of a tooth (ATD6-92) from TD6 unit of Atapuerca Gran Dolina (Spain) following a “semi non-destructive” procedure provides a final age estimate ranging from 624 to 949 ka, which covers all possible uranium uptake scenarios. Last, the additional magnetostratigraphic data collected within TD6 enables to further constrain the initial ESR chronology and to propose an age of between 772 and 949 ka for Homo antecessor, in agreement with previous dating works. Although our new results do not refine the existing chronology of TD6 unit, they nevertheless support the antiquity of H. antecessor, which pre-dates the estimated divergence age of modern and archaic human lineages based on genetic evidence. This work illustrates the challenges of dating human teeth by means of the ESR method, with the main pitfalls that are sometimes inherent to this specific application (e.g., systematic μCT-scanning of fossil hominin teeth; limited knowledge about the original sedimentary environment for teeth coming from old excavations; heterogeneous spatial distribution of the U-series elements in dental tissues). We identified several sources of uncertainty that may directly impact the accuracy of the age result. In particular, a slight contamination of dentine (<6%) in the enamel fragment measured by ESR was found to induce a significant age underestimation (33%) if not taken into consideration. It indeed caused not only a DE underestimation (by about 8%), but also produced a massive internal dose rate overestimation (by a factor of about 3.5). In contrast, other sources of uncertainty, such as the heterogeneity of the sedimentary environment, the variability of the water content over time, the previous μCT-scanning of the tooth or the potential preferential creation of unstable NOCORs in the ESR signal, showed here a limited impact on the final age result. Given our current understanding of the ESR method and the existing uncertainties associated with the evaluation of the DE and dose rate, this is probably as far as we can presently go in the dating study of ATD6-92 sample

Immigrant IBD Patients in Spain Are Younger, Have More Extraintestinal Manifestations and Use More Biologics Than Native Patients

BackgroundPrevious studies comparing immigrant ethnic groups and native patients with IBD have yielded clinical and phenotypic differences. To date, no study has focused on the immigrant IBD population in Spain. MethodsProspective, observational, multicenter study comparing cohorts of IBD patients from ENEIDA-registry who were born outside Spain with a cohort of native patients. ResultsWe included 13,524 patients (1,864 immigrant and 11,660 native). The immigrants were younger (45 +/- 12 vs. 54 +/- 16 years, p < 0.001), had been diagnosed younger (31 +/- 12 vs. 36 +/- 15 years, p < 0.001), and had a shorter disease duration (14 +/- 7 vs. 18 +/- 8 years, p < 0.001) than native patients. Family history of IBD (9 vs. 14%, p < 0.001) and smoking (30 vs. 40%, p < 0.001) were more frequent among native patients. The most prevalent ethnic groups among immigrants were Caucasian (41.5%), followed by Latin American (30.8%), Arab (18.3%), and Asian (6.7%). Extraintestinal manifestations, mainly musculoskeletal affections, were more frequent in immigrants (19 vs. 11%, p < 0.001). Use of biologics, mainly anti-TNF, was greater in immigrants (36 vs. 29%, p < 0.001). The risk of having extraintestinal manifestations [OR: 2.23 (1.92-2.58, p < 0.001)] and using biologics [OR: 1.13 (1.0-1.26, p = 0.042)] was independently associated with immigrant status in the multivariate analyses. ConclusionsCompared with native-born patients, first-generation-immigrant IBD patients in Spain were younger at disease onset and showed an increased risk of having extraintestinal manifestations and using biologics. Our study suggests a featured phenotype of immigrant IBD patients in Spain, and constitutes a new landmark in the epidemiological characterization of immigrant IBD populations in Southern Europe

Revisión y estudio de las manifestaciones paleopatológicas en los homininos del plio-pleistoceno, con especial referencia a algunos fósiles de la Sierra de Atapuerca

La paleopatología es la disciplina que estudia las enfermedades del pasado a través del análisis del registro fósil para definir el perfil de morbosidad sufrido por el individuo o el conjunto de la población. Para ello utiliza un diagnóstico retrospectivo, extrapolando las consecuencias de la enfermedad para conocer sus causas. El patrón de enfermedad que afecta a una población es el resultado del estrés al que está sujeta dicha población. Los estudios de evolución humana requieren de otras disciplinas, además de la antropología evolutiva, para obtener un escenario más completo que incluya las estrategias de subsistencia, patrones de comportamiento y nicho ecológico. La contribución original presentada en esta disertación es un acercamiento alternativo, a través del análisis paleopatológico, para abordar el estudio de la evolución humana. Obviar los signos paleopatológicos nos llevaría a ignorar una valiosa fuente de información sobre el estudio de vida de los homininos y su adaptación al nicho ecológico. Es decir, en estas poblaciones los rigores de la vida diaria habrían dejado una huella en los esqueletos que necesita ser interpretada para elucidar la presión y estrés a las que han estado sometidos. El estudio de la cuadros patológicos consiste primordialmente en la identificación, la descripción detallada de la lesión, el diagnóstico, cuando es posible, e inferencias sobre actividades que puedan haber causado las lesiones. Para ello y junto con la técnica macroscópica, se aplicaron a los restos fósiles en estudio tres técnicas microscópicas: Tomografía Computarizada (CT), microtomografía (mCT) y Microscopio Electrónico de Barrido (ESEM). Los objetivos de esta tesis comprenden: a) identificación y descripción de las lesiones que afecten los restos fósiles humanos de los yacimientos del Pleistoceno de Atapuerca y de otros homínidos, provenientes de yacimientos euroasiáticos, relacionados filogenéticamente con las de Atapuerca o que comparten un marco geográfico y/o cronológico con éstas; b) presentar una hipótesis diagnóstica y diagnóstico diferencial; c) prognosis, evolución y evaluación de las implicaciones que tienen a nivel de comportamiento o adaptación sobre el individuo las lesiones identificadas; d) evaluación de los grados de alteración morfológica causada por los cuadros patológicos y su interferencia en la caracterización taxonómica; y por último f) una síntesis y revisión crítica de los estudios paleopatológicos del registro fósil y una evaluación del perfil de morbosidad de nuestros ancestros. La identificación de cuadros patológicos en poblaciones extintas, por leves que sean, habrían además repercutido de manera indirecta en otros elementos anatómicos, provocando irreparables modificaciones en la anatomía del individuo. Los resultados obtenidos evidencian un patrón caracterizado principalmente por cuadros dentognáticos y traumáticos. Homo neanderthalensis es la especie que presenta mayor frecuencia y variedad de cuadros patológicos. Los factores de comportamiento relacionados con las lesiones identificadas incluyen, entre otros: tipo de dieta, actividades locomotoras y violencia. En general la prognosis de la enfermedad supuso el avance y empeoramiento de la salud del individuo. En algunos casos también se ha observado signos de cicatrización y recuperación. A nivel de repercusión para el individuo, dependiendo del elemento afectado en el cuadro patológico, se han sugerido desde pequeñas molestias hasta lesiones incapacitantes a nivel de movimiento o alimentación

On the variability of the Dmanisi mandibles.

The description of a new skull (D4500) from the Dmanisi site (Republic of Georgia) has reopened the debate about the morphological variability within the genus Homo. The new skull fits with a mandible (D2600) often referred as 'big' or 'enigmatic' because of its differences with the other Dmanisi mandibles (D211 and D2735). In this report we present a comparative study of the variability of the Dmanisi mandibles under a different perspective, as we focus in morphological aspects related to growth and development. We have followed the notion of modularity and phenotypic integration in order to understand the architectural differences observed within the sample. Our study reveals remarkable shape differences between D2600 and the other two mandibles, that are established early in the ontogeny (during childhood or even before) and that do not depend on size or sexual dimorphism. In addition, D2600 exhibits a mosaic of primitive and derived features regarding the Homo clade, which is absent in D211 and D2735. This mosaic expression is related to the location of the features and can be explained under the concept of modularity. Our study would support the possibility of two different paleodemes represented at the Dmanisi site. This hypothesis has been previously rejected on the basis that all the individuals were constrained in the same stratigraphic and taphonomic settings. However, our revision of the complex Dmanisi stratigraphy suggests that the accumulation could cover an undetermined period of time. Even if "short" in geological terms, the hominin accumulation was not necessarily synchronic. In the same line we discard that the differences between D2600 and the small mandibles are consequence of wear-related dentoalveolar remodeling. In addition, dental wear pattern of D2600 could suggest an adaptation to a different ecological niche than the other Dmanisi individuals

Dental tissue proportions and linear dimensions of Sima de los Huesos lower incisors

Objectives To assess the phenotypic affinities of the Sima de los Huesos (SH) mandibular incisors dental tissue proportions, and radicular dimensions, relative to Neandertals, recent modern humans (RMH), and a large comparative sample of Pleistocene hominins. Materials and Methods Two dimensional (2D) and three dimensional (3D) data were extracted from SH (n = 22) incisors, and compared with specimens from Krapina (n = 6) and Ehringsdorf (n = 2), RMH (n = 42), as well as a comparative sample of hominins from the literature (n = 244). We calculated average enamel thickness (AET), relative enamel thickness (RET) and radicular variables (cervical area [CA] and root surface area [RSA], root linear dimensions [RL], dentine and pulp volume [RDV, RPV, TRV]). Results We found that SH incisor crown variables were generally undiagnostic for 2D and 3D AET and 2D RET. Trends indicated thicker 3D RET in RMH relative to SH hominins, Tighenif hominins, and Neandertals. The SH and Neandertal mandibular incisors share similar RL, RSA, and root tissue volumes when compared to other extinct members of Homo. Relative to all other extinct hominins examined here, SH incisors display a relatively narrow cervical labio-lingual diameter. Finally, we found a weak correlations in SH and RMH between the crown and root variables. Discussion This study confirms that SH mandibular incisors' dental tissue proportions and root dimensions align more closely to Neandertals. However, the complete set of Neandertal apomorphies is not present within SH mandibular incisors. SH incisors concur with traits reported in SH canines, and contrasting patterns in the molars, revealing a dichotomy between the anterior and posterior teeth for dental tissue proportions

List of mandibular morphological features considered in this study.

<p>List of mandibular morphological features considered in this study.</p

Detail of the left side of D2600.

<p>Note the molarized root bifurcation of the left P3.</p

Paléopathologie du spécimen pléistocène D2600 de Dmanisi (république de Géorgie)

Here we present a detailed palaeopathological study of the hominin mandible D2600 recov-ered at the Dmanisi site, Republic of Georgia. The Dmanisi assemblage represents theearliest evidence of hominins outside Africa with an age of 1.8 Ma. D2600 is the holotypeof Homo georgicus species and its taxonomic assignment is still under debate. Our studyreveals severe and unusual dental wear accompanied of extensive root exposure and dental axial migration, periapical abscesses and enamel fractures. In addition, there is evidenceof post-eruptive tooth rotation and temporomandibular arthropathy. We propose that thewear pattern observed in this individual is related to a diet with a high intake of fibrousand abrasive foods such as fruits and plants, as it is usually recorded in chimpanzees andgorillas and unlike the wear pattern observed in other Homo specimens of our comparativesample. The rounded occlusal surfaces and highly polished labio-lingual surfaces of D2600anterior teeth could be mainly the consequence of pre - and/or para-masticatory activi-ties such as gripping and stripping. This type of food would be also the origin of the highlycupped occlusal morphology of the posterior dentition in combination with relatively slightapproximal attrition. However, the lesions exhibited by D2600 have not significantly alteredthe morphology of the mandible and do not prevent a proper taxonomic assessment.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu