Behavioral strategies of prehistoric and historic children from dental microwear texture analysis

Introduction: Reconstructing the dietary and behavioral strategies of our hominin ancestors is crucial to understanding their evolution, adaptation, and overall way of life. Teeth in general, and dental microwear specifically, provide a means to examine these strategies, with posterior teeth well positioned to tell us about diet, and anterior teeth helping us examine non-dietary tooth-use behaviors. Past research predominantly focused on strategies of adult individuals, leaving us to wonder the role children may have played in the community at large. Here we begin to address this by analyzing prehistoric and historic children through dental microwear texture analysis of deciduous anterior teeth. Materials and Methods: Four sample groups were used: Neandertals (N = 8), early modern humans (N = 14), historic Egyptians from Amarna (N = 19) and historic high-Arctic Inuit from Point Hope, Alaska (N = 6). Anterior deciduous teeth were carefully cleaned, molded, and cast with high-resolution materials. Labial surfaces were scanned for dental microwear textures using two white-light confocal microscopes at the University of Arkansas, and a soft filter applied to facilitate data comparisons. Results and Discussion: Results show that dental microwear texture analysis successfully differentiated the samples by all texture variables examined (anisotropy, complexity, scale of maximum complexity, and two variants of heterogeneity). Interestingly, the Neandertal and Point Hope children had similar mean values across all the texture variables, and both groups were significantly different from the Amarna, Egyptian children. These differences suggest diversity in abrasive load exposure and participation in non-dietary anterior tooth-use behaviors. Further analyses and an expanded sample size will help to strengthen the data presented here, but our results show that some prehistoric and historic children took part in similar behaviors as their adult counterparts.The work was supported by the AE is supported by H2020-MSCA-IF project No. 891529 (3DFOSSILDIET)This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 89152

Evidence of habitual behavior from non-alimentary dental wear on deciduous teeth from the Middle and Upper Paleolithic Cantabrian region, Northern Spain

The use of "teeth as tools" (non-masticatory or cultural-related dental wear) has largely been employed as a proxy for studying of past human behavior, mainly in permanent dentition from adult individuals. Here we present the analysis of the non-masticatory dental wear modifications on the deciduous dentition assigned to eight Neanderthal and anatomically modern human subadult individuals from Mousterian to Magdalenian technocultural contexts in the Cantabrian region (Northern Spain). Although preliminary, we tentatively suggest that these eight subadults present activity-related dental wear, including cultural striations, chipped enamel, toothpick grooves, and subvertical grooves. We also found evidence of habitual dental hygienic practices in the form of toothpicking on a deciduous premolar. Orientation of the cultural striations indicates similar handedness development as in modern children. Taken together, these dental wear patterns support the participation of young individuals in group activities, making them potential contributors to group welfare. This study potentially adds new evidence to the importance of the use of the mouth in paramasticatory activities or as a third hand throughout the Pleistocene, which can be confirmed with a more specific reference sample.We thank the curators at the following museums for providing access to the collections: Museo de Arqueología de Asturias (Las Caldas and Tito Bustillo), Museo de Prehistoria y Arqueología de Cantabria (El Castillo) and Arkeologi Museoa (Santa Catalina and Axlor).We are very grateful to the Editors-in-Chief (David Alba and Clément Zanolli), the Associate Editor, and reviewers for their comments and suggestions, which greatly improved the quality of this paper. A.E. was beneficiary of a Juan de la Cierva-Formaci on Postdoctoral Fellowship (grant number FJCI-2016-30122). Partial aspects of this research have been founded by SUBSILIENCE ERCProject (ERCEA-; grant agreement No. 818299), ABRUPT project (HAR2017-84997-P Spanish Ministry of Science, Innovation and Universities) and Santander Bank within the program of Santander Talent Attraction for Research (STAR1) to A.B.M.A., and H2020- MSCA-IF project No. 891529 (3DFOSSILDIET) to A.E

Algoritmo para optimizar los ángulos de ataque de un UGV en función del terreno discretizando

El objetivo principal de este proyecto es conseguir optimizar la elección de los ángulos de ataque del UGV definido mediante la variación de los ángulos de ataque de cada uno de sus brazos por separado. Se debe de conseguir un algoritmo de cálculo el cual permita al vehículo orientar los ángulos de ataque de sus brazos de forma autónoma. Con tal de conseguir este objetivo principal, se definen los siguientes objetivos: Crear un modelo básico del vehículo en 2D que permita desarrollar todo el trabajo de una manera adecuada. Calcular un modelo viable, que permita llevar a cabo el análisis y el cálculo cinemático y dinámico del vehículo para cualquier función suelo y cualquier configuración angular del vehículo, con la finalidad de obtener el par necesario que permita al vehículo desplazarse a través de la trayectoria. Dotar al modelo de la mayor polivalencia posible, haciendo que pueda ser utilizado para la mayor variedad de tipos de función suelo. Crear un algoritmo de programación el cual implemente el modelo y sea además capaz de llevar a cabo una optimización para obtener las configuraciones angulares más óptimas a lo largo de la trayectoria. Analizar los resultados y sacar las conclusiones pertinentes.Ingeniería Industria

Paleobiología del linaje Neandertal: paleodieta y marcadores de actividad en la dentición de los fósiles humanos de la cueva de El Sidrón (Asturias)

Tesis doctoral inédita leída en la Universida Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología. Fecha de lectura: 05-02-201

Activity markers on the anterior dentition of Neandertals: the case of cultural striations

Comunicación presentada en el XIII Encuentro en Jóvenes Investigadores en Paleontología (XIII EJIP) - XIII Meeting of Early-Stage Researchers in Paleontology (XIII EJIP): Cercedilla, 15 - 18 de Abril de 2015Este trabajo ha sido financiado por el proyecto CGL2012-36682 (MINECO)Peer reviewe

A preliminary assessment of the thoracic remains of the El Sidrón Neandertals (Asturias, Spain)

Resumen del póster presentado en: 3rd Annual Meeting of the European Society for the study of Human Evolution, 19-21 September 2013, Vienna/AustriaPeer reviewe

Genetic evidence for patrilocal mating behaviour among Neandertal groups

The remains of 12 Neandertal individuals have been found at the El Sidrón site (Asturias, Spain), consisting of six adults, three adolescents, two juveniles, and one infant. Archaeological, paleontological, and geological evidence indicates that these individuals represent all or part of a contemporaneous social group of Neandertals, who died at around the same time and later were buried together as a result of a collapse of an underground karst. We sequenced phylogenetically informative positions of mtDNA hypervariable regions 1 and 2 from each of the remains. Our results show that the 12 individuals stem from three different maternal lineages, accounting for seven, four, and one individual(s), respectively. Using a Y-chromosome assay to confirm the morphological determination of sex for each individual, we found that, although the three adult males carried the same mtDNA lineage, each of the three adult females carried different mtDNA lineages. These findings provide evidence to indicate that Neandertal groups not only were small and characterized by low genetic diversity but also were likely to have practiced patrilocal mating behavior.C.L.-F. also is supported by an Intramural Grant from the Consejo Superior de Investigaciones Cientificas. A.R., A.E., M.B., A.G.-T., and S.G.-V. are supported by Grant CGL2009-09013 from the Ministry of Science and Innovation of Spain.Peer reviewe

Possible further evidence of low genetic diversity in the El Sidrón (Asturias, Spain) Neandertal group: congenital clefts of the Atlas

Received: June 12, 2015; Accepted: August 5, 2015; Published: September 29, 2015We 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.Funding was provided by Ministerio de Economía y Competitividad, Spain, projects CGL2012-36682 and CGL2012-37279.Peer reviewe

Preconditioned iterative methods for convection diffusion and related boundary value problems

AbstractWe develop and analyze preconditioners for the iterative solution of the system of equations arising from the discretization of multi-dimensional singularity perturbed boundary value problems. This includes a class of convection diffusion models. The choice of preconditioner is crucial for the efficient solution of the system of equations. In particular, it is necessary to choose a preconditioner that substantially reduces the condition number κ both for small grid size h and for large values of the parameter K multiplying the convection terms. A class of preconditioners is analyzed that is inexpensive to implement and for which κ = 0(1) as h→0 and κ = (1 + K12) as K → ∞ for some convection diffusion problems with positive definite symmetric part. This result is then used to develop an algorithm with work estimate 0(1 + K12as K → ∞ for a more general class of convection diffusion problems including those with indefinite symmetric part. Numerical experiments using a symmetric multigrid preconditioner demonstrate the effectiveness of the numerical method even for large problems

Response to comment on “The growth pattern of Neandertals, reconstructed from a juvenile skeleton from El Sidrón (Spain)”

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