The Sima de los Huesos cervical spine

Information regarding the evolution of the neck in genus Homo is hampered owing to a limited fossil record. Neandertals display significant metric and/or morphological differences in all the cervical vertebrae, when compared to Homo sapiens. Thus, the important fossil record from the Middle Pleistocene site of Sima de los Huesos (SH) not only offers important information about the evolution of this anatomical region within the Neandertal lineage, but also provides important clues to understand the evolution of this region at the genus level. We present the current knowledge of the anatomy of the cervical spine of the hominins found in SH compared to that of Neandertals and modern humans, and, when possible, to Homo erectus and Homo antecessor. The current SH fossil record comprises 172 cervical specimens (after refittings) belonging to a minimum of 11 atlases, 13 axes, and 52 subaxial cervical vertebrae. The SH hominins exhibit a morphological pattern in their cervical spine more similar to that of Neandertals than that of H. sapiens, which is consistent with the phylogenetic position of these hominins. However, there are some differences between the SH hominins and Neandertals in this anatomical region, primarily in the length and robusticity, and to a lesser extent in the orientation of the spinous processes of the lowermost cervical vertebrae. We hypothesize that these differences in the lowermost subaxial cervical vertebrae could be related to the increase in the brain size and/or changes in the morphology of the skull that occurred in the Neandertal lineage.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEMinisterio de Ciencia e InnovaciónJunta de Castilla y LeónFundación Atapuercapu

Failure mode prediction and energy forecasting of PV plants to assist dynamic maintenance tasks by ANN based models

In the field of renewable energy, reliability analysis techniques combining the operating time of the system with the observation of operational and environmental conditions, are gaining importance over time. In this paper, reliability models are adapted to incorporate monitoring data on operating assets, as well as information on their environmental conditions, in their calculations. To that end, a logical decision tool based on two artificial neural networks models is presented. This tool allows updating assets reliability analysis according to changes in operational and/or environmental conditions. The proposed tool could easily be automated within a supervisory control and data acquisition system, where reference values and corresponding warnings and alarms could be now dynamically generated using the tool. Thanks to this capability, on-line diagnosis and/or potential asset degradation prediction can be certainly improved. Reliability models in the tool presented are developed according to the available amount of failure data and are used for early detection of degradation in energy production due to power inverter and solar trackers functional failures. Another capability of the tool presented in the paper is to assess the economic risk associated with the system under existing conditions and for a certain period of time. This information can then also be used to trigger preventive maintenance activities

Morphological integration in the gorilla, chimpanzee, and human neck.

OBJECTIVES: Although integration studies are important to understand the evolution of organisms' traits across phylogenies, vertebral integration in primates is still largely unexplored. Here we describe and quantify patterns of morphological integration and modularity in the subaxial cervical vertebrae (C3-C7) in extant hominines incorporating the potential influence of size. MATERIALS AND METHODS: Three-dimensional landmarks were digitized on 546 subaxial cervical vertebrae from 141 adult individuals of Gorilla gorilla, Pan troglodytes, and Homo sapiens. Integration and modularity, and the influence of size effects, were quantified using geometric morphometric approaches. RESULTS: All subaxial cervical vertebrae from the three species show a strong degree of integration. Gorillas show the highest degree of integration; conversely, humans have the lowest degree of integration. Analyses of allometric regression residuals show that size is an important factor promoting integration in gorillas, with lesser influence in chimpanzees and almost no effect in humans. DISCUSSION: Results point to a likely ancestral pattern of integration in non-human hominines, whereby the degree of integration decreases from cranial to caudal positions. Humans deviate from this pattern in the cranialmost (C3) and, to a lesser extent, in the caudalmost (C7) vertebrae, which are less integrated. These differences can be tentatively related to the emergence of bipedalism due to the presence of modern human-like C3 in australopiths, which still preserve a more chimpanzee-like C7

Covariation between the cranium and the cervical vertebrae in hominids

[EN] The analysis of patterns of integration is crucial for the reconstruction and understanding of how morphological changes occur in a taxonomic group throughout evolution. These patterns are relatively constant; however, both patterns and the magnitudes of integration may vary across species. These differences may indicate morphological diversification, in some cases related to functional adaptations to the biomechanics of organisms. In this study, we analyze patterns of integration between two functional and developmental structures, the cranium and the cervical spine in hominids, and we quantify the amount of divergence of each anatomical element through phylogeny. We applied these methods to three-dimensional data from 168 adult hominid individuals, summing a total of more than 1000 cervical vertebrae. We found the atlas (C1) and axis (C2) display the lowest covariation with the cranium in hominids (Homo sapiens, Pan troglodytes, Pan paniscus, Gorilla gorilla, Gorilla beringei, Pongo pygmaeus). H. sapiens show a relatively different pattern of craniocervical correlation compared with chimpanzees and gorillas, especially in variables implicated in maintaining the balance of the head. Finally, the atlas and axis show lower magnitude of shape change during evolution than the rest of the cervical vertebrae, especially those located in the middle of the subaxial cervical spine. Overall, results suggest that differences in the pattern of craniocervical correlation between humans and gorillas and chimpanzees could reflect the postural differences between these groups. Also, the stronger craniocervical integration and larger magnitude of shape change during evolution shown by the middle cervical vertebrae suggests that they have been selected to play an active role in maintaining head balance.We would like to express our gratitude for access and technical help with the collections to Patrice Courtaud (Université de Bordeaux), Jacques Cuisin (MNHN, Paris), Emmanuel Gilissen and Wim Wendelen (Royal Museum for Central Africa, Tervuren), Olivier S. G. Pauwels and Patrick Semal (Royal Belgian Institute of Natural Sciences), Javier Quesada (Nat-Museu de Ciències Naturals, Barcelona), and Inbal Livne (Powell-Cotton Museum, Birchington, UK). This research has also received support from the Spanish Ministry of Science and Innovation through the “María de Maeztu” excellence accreditation (CEX2019-000945- M), FEDER/Ministerio de Ciencia e Innovación-Agencia Estatal de Investigación (project PGC2018-093925-B-C33), Research Group IT1418-19 from the Eusko Jaurlaritza-Gobierno Vasco, AGAUR (Ref. 2017SGR1040) and URV (Ref. 2019PFR-URV-91). A.G.O. was supported by the Ramón y Cajal fellowship (RYC-2017-22558)

New postcranial remains from the Roc de Marsal Neandertal child

This paper presents the identification and study of three new human fossil remains belonging to the Neandertal child Roc de Marsal, found in the eponymous cave site, located near Campagne-de-Bugue, Dordogne, France. These three new fragments correspond to a right clavicle shaft fragment, a shaft fragment of the right radius and the dorsal part of a shaft fragment of hand (likely proximal) phalanx. These elements further complete the state of preservation of the skeleton. This work underlines the necessity to review “old collections”. We propose the hypothesis that additional taphonomic studies could, in some cases, allow discussion of certain skeletal representation.Cet article présente l’identification et l’étude de trois nouveaux restes fossiles humains appartenant à l’enfant néandertalien Roc de Marsal , trouvé dans la grotte éponyme, située près de Campagne-du-Bugue, Dordogne, France. Ces trois nouvelles pièces correspondent à un fragment de diaphyse de clavicule droite, de diaphyse de radius droit et d’une phalange (probablement proximale) de main. Ces différents éléments complètent le squelette. La présente étude souligne la nécessité de revoir les « anciennes collections ». Nous proposons l’hypothèse que la réalisation d’études taphonomiques complémentaires pourrait, dans quelques cas, permettre alors de discuter la représentation squelettique

Single-grain OSL dating of the Middle Palaeolithic site of Galería de las Estatuas, Atapuerca (Burgos, Spain)

This study presents single-grain optically stimulated luminescence (OSL) chronologies for the archaeological site of Galería de las Estatuas – the first systematically excavated Middle Palaeolithic site within the karst system of the Sierra de Atapuerca archaeological complex, northern Spain. The single-grain OSL ages are compared with paired single-grain thermally transferred OSL (TT-OSL) dating results for a selection of samples in order to better assess quartz signal bleaching characteristics of endokarstic deposits preserved at Atapuerca. In total, seven luminescence dating samples were collected from four lithostratigraphic units exposed in two excavation pits (GE-I and GE-II). The single-grain OSL equivalent dose (De) distributions are characterised by generally low overdispersion (20–30%), suggesting appropriate bleaching at deposition. The resultant single-grain OSL ages reveal that the sediment sequence and archaeological remains excavated in pit GE-I accumulated 80–112 ka, while the upper layers of excavation area GE-II were deposited 70–79 ka. The replicate single-grain TT-OSL ages are in agreement with the OSL chronologies at 2σ for three of the four samples investigated; although in all cases the TT-OSL ages were systematically older than their single-grain counterparts. Apparent TT-OSL residual doses (i.e., TT-OSL De values in excess of their corresponding OSL De values) of 9–65 Gy were observed for all samples. These excess TT-OSL De values are generally low in comparison to the natural dose ranges of TT-OSL dating applications undertaken elsewhere in the Atapuerca karst system. The single-grain TT-OSL and OSL dating comparisons build on daylight bleaching experiments and modern analogue studies performed on other Atapuerca exogeneous infill deposits and suggest reasonable potential for TT-OSL signal resetting down to relatively low levels for at least some sediments preserved in the Atapuerca karstic cavities. The quartz single-grain OSL chronologies obtained in this study place the Middle Palaeolithic sequence of Galería de las Estatuas within marine isotope stage (MIS) 5 and the beginning of MIS 4, and provide firm evidence for human occupation of the Sierra de Atapuerca during a previously unreported time period

The evolutionary ecology of the endemic European Eocene Plagiolophus (Mammalia: Perissodactyla)

The climatic cooling that began in the late middle Eocene and culminated in the Eocene-Oligocene transition meant major changes in Palaeotheriidae (Perissodactyla, Mammalia) biodiversity in Europe and could have caused the appearance of new dietary strategies. This work is the first to study the spatiotemporal response of one palaeotheriid genus (Plagiolophus) to the Eocene environmental and ecological changes using three dietary proxies: hypsodonty, mesowear and dental microwear texture analysis (DMTA). DMTA is applied for the first time to palaeotheriids. The high diversity and wide chrono-spatial distribution of Plagiolophus make it possible to evaluate spatiotemporal environmental variations, including palaeodiet. We study five Plagiolophus samples from late middle Eocene to early Oligocene from western Iberia to central Europe in order to (1) infer lifetime palaeodiet; (2) infer short-term palaeodiet; and (3) test temporal and spatial trends. All samples present an exclusion of abrasive foodstuff given low hypsodonty index; dominance of browsing given the low mesowear score; and browsing of tough foliage and exclusion of hard items in their diet given DMTA information. These factors point to Plagiolophus as a highly selective feeder that fed on plants with the same features irrespective of chronology or location: tough foliage (leaves from monocots or dicots) avoiding lignified or hard materials, without seasonal variations.Financial support was provided by the Spanish Ministry of Science, Innovation and Universities and the European Regional Development Fund (projects CGL2017–85038-P and PGC2018–093925-B-C33), the Basque Country Government (research groups of the Gobierno Vasco/Eusko Jaurlaritza IT1004–16 and IT418–19) and the UPV/EHU (PPG17/04). LPG received a pre-doctoral grant from the UPV/EHU (PIF16/190). AGO is supported by a Ramon y Cajal fellowship (RYC-2017-22558). GM is funded by ANR TRIDENT (ANR-13-JSV7–0008-01, PI: GM)