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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.

Inferences of function and ecology in extinct taxa have long been a subject of interest because it is fundamental to understand the evolutionary history of species. In this study, we use a quantitative approach to investigate the locomotor behaviour of Simocyon batalleri, a key taxon related to the ailurid family. To do so, we use 3D surface geometric morphometric approaches on the three long bones of the forelimb of an extant reference sample. Next, we test the locomotor strategy of S. batalleri using a leave-one-out cross-validated linear discriminant analysis. Our results show that S. batalleri is included in the morphospace of the living species of musteloids. However, each bone of the forelimb appears to show a different functional signal suggesting that inferring the lifestyle or locomotor behaviour of fossils can be difficult and dependent on the bone investigated. This highlights the importance of studying, where possible, a maximum of skeletal elements to be able to make robust inferences on the lifestyle of extinct species. Finally, our results suggest that S. batalleri may be more arboreal than previously suggested., MJS and JM belong to the Research Group UCM-BSCH 910607.

The clade Archosauria contains two very different sister groups in terms of diversity (number of species) and disparity (phenotypic variation): Crurotarsi (taxa more closely related to crocodiles than to birds) and Ornithodira (pterosaurs and dinosaurs including birds). The extant species of Crurotarsi may constitute a biased sample of past biodiversity regarding growth patterns and metabolic rates. Bone histological characters can be conserved over hundreds of millions of years in the fossil record and potentially contain information about individual age at death, age at sexual maturity, bone growth rates, and basal metabolic rates of extinct vertebrates. Using a sample of extant amniotes, we have constructed a paleobiological model to estimate bone growth rate from bone histological traits. Cross-validation tests show that this model is reliable. We then used it to estimate bone growth rates in a sample of extinct archosaurs including Crurotarsi and Ornithodira. After testing for phylogenetic signal, optimization of femoral growth rates through squared change parsimony onto a time-calibrated tree of amniotes shows two divergent evolutionary trends: whereas bone growth rates increase from the last common ancestor of Ornithodira to extant birds, they decrease from the last common ancestor of Crurotarsi to extant crocodiles. However, we conclude, on the basis of recent evidence for unidirectional airflow in the lungs of alligators, that crocodiles may have retained the capacity of growing at high rates., This study was partly funded by the PPF Biomineralisations of the Universite´ Pierre et Marie Curie – Paris VI. C.M.M. was funded by the National Human Resources Mobility Programme under the I+D+i 2008–2011 National Plan of the Spanish Ministry of Science and Innovation (MICINN).

International audience; Ante todo queremos expresar nuestro más sinceroagradecimiento a todos los que han contribuido alvolumen homenaje dedicado a Leonard Ginsburgque aquí presentamos. Nuestra gratitud a José MaríaCebriá editor de Estudios Geológicos, por su apoyoincondicional durante todo el proceso de elabora-ción del volumen. También queremos expresarnuestro agradecimiento a Luís Gómez Argüero porsu dedicación e inestimable ayuda desde la Secreta-ría de la Revista. Esperamos que este homenaje anuestro querido amigo y compañero Leonard Gins-burg sea recibido con agrado.Leonard Ginsburg (1927-2009)1ha marcado todauna época en la Paleontología de mamíferos euro-pea, su dedicación a la sistemática de los mamíferosfósiles es inconmensurable, más de 50 años de traba-jo, desde sus comienzos a principios de los años 50del siglo XX, hasta sus últimas aportaciones, publi-cadas durante los primeros años del presente siglo.Son centenares de trabajos, que hoy son fundamen-tales para todos aquellos que todavía aman y sededican a la clasificación de los mamíferos fósiles.

Developmental and evolutionary changes in craniofacial morphology are a central issue in paleoanthropology, but the underlying bone growth processes have been scarcely studied. Relevant knowledge on bone growth dynamics can be obtained from the spatial distribution of bone formation and resorption activities. Determining these patterns from the valuable samples typically used in anthropology and palaeoanthropology necessarily implies nondestructive procedures. In this work, we present a methodology based on the analysis of high-resolution replicas by reflected light microscopy, describing how microfeatures related to bone formation and resorption activities are recognized on both recent and fossil bone surfaces. The proposed method yields highly similar images to those obtained with scanning electron microscope and has proven its utility in an analysis of a large sample of extant and extinct hominoids.

International audience; Etosha Pan, northern Namibia, at nearly 5,000 km', is one of the largest in the world. A major hurdle to understanding the geological history of Etosha Pan has been the lack of dated horizons in the local stratigraphic record. We here report the discovery of fossil plants, invertebrates and vertebrates at several distinct horizons within the pan and its immediate vicinity, which reveal the presence of deposits ranging in age from Late Miocene to Late Pleistocene. Most of the floor of the pan consists of Late Miocene deposits whereas in islands and ridges within the pan and along its margins there occurs a discontinuous deposit of Pliocene, Pleistocene sediments up to 20 metres thick. Finally, there are discontinuous patches of green silts on Pelican Island at an altitude of ca 1093 metres, some 8-10 metres above the floor of the pan, which attest to a Late Pleistocene lacustrine episode. Similar aged deposits at the western end of Oshigambo Peninsula has yielded a rich and diverse mammalian fauna containing remains of the aquaphile bovid Tragelaphus spekei (the sitatunga). The discovery of Mio-Pliocene fossils in Elosha is important as it helps to fill whal used to be a large geographic gap in the African palaeonlological map of this epoch. Laie Miocene sites in particular, are poorly represented over much of the continent, being concentrated in the rift valleys of East Africa, the Chad basin, the Maghreb and north African littoral zone. ­

The thickness of dental enamel is often discussed in paleoanthropological literature, particularly with regard to differences in growth, health, and diet between Neandertals and modern humans. Paleoanthropologists employ enamel thickness in paleodietary and taxonomic studies regarding earlier hominins, but variation in enamel thickness within the genus Homo has not been thoroughly explored despite its potential to discriminate species and its relevance to studies of growth and development. Radiographic two-dimensional studies indicate that Neandertal molar enamel is thin relative to the thick enamel of modern humans, although such methods have limited accuracy. Here we show that, measured via accurate high-resolution microtomographic imaging, Neandertal molar enamel is absolutely and relatively thinner than modern human enamel at most molar positions. However, this difference relates to the ratio of coronal dentine volume to total crown volume, rather than the quantity of enamel per se. The absolute volume of Neandertal molar enamel is similar to that of modern humans, but Neandertal enamel is deposited over a larger volume of coronal dentine, resulting in lower average (and relative) enamel thickness values. Sample sizes do not permit rigorous intragroup comparisons, but Neandertal molar tissue proportions evince less variation than the modern human sample. Differences in three- and two-dimensional enamel thickness data describing Neandertal molars may be explained by dimensional reduction. Although molar tissue proportions distinguish Neanderthals from recent Homo sapiens, additional study is necessary to assess trends in tissue proportions in the genus Homo throughout the Pleistocene.

Both the giant panda (Ailuropoda melanoleuca) and the red panda (Ailurus fulgens) possess a 'false-thumb', actually an enlarged radial sesamoid bone, which contributes to the gripping action of the hand. These species are not closely related, however, as one is an ursid and the other an ailurid, so the fact that they share this adaptation implies a remarkable convergence. We studied the functional anatomy of this structure in the red panda, comparing it with existing descriptions of the grasping mechanism in both pandas. Previous interpretations of the radial sesamoid in Ailurus as a rod-like structure without direct articulation to the wrist bones are inaccurate. There are various important differences between the red panda and the giant panda. In the former, the lesser development of the radial sesamoid, its connection with the flexor retinaculum, the presence of an insertion of the muscle abductor pollicis longus in the first metacarpal, which enhances its supinatory action, and the presence of a muscle flexor brevis digitorum manus point to thin-branch climbing features serving as an exaptation to the more recent role of the red panda hand in the manipulation of bamboo.

The “false thumb” of pandas is a carpal bone, the radial sesamoid, which has been enlarged and functions as an opposable thumb. If the giant panda ( Ailuropoda melanoleuca ) and the red panda ( Ailurus fulgens ) are not closely related, their sharing of this adaptation implies a remarkable convergence. The discovery of previously unknown postcranial remains of a Miocene red panda relative, Simocyon batalleri , from the Spanish site of Batallones-1 (Madrid), now shows that this animal had a false thumb. The radial sesamoid of S. batalleri shows similarities with that of the red panda, which supports a sister-group relationship and indicates independent evolution in both pandas. The fossils from Batallones-1 reveal S. batalleri as a puma-sized, semiarboreal carnivore with a moderately hypercarnivore diet. These data suggest that the false thumbs of S. batalleri and Ailurus fulgens were probably inherited from a primitive member of the red panda family (Ailuridae), which lacked the red panda's specializations for herbivory but shared its arboreal adaptations. Thus, it seems that, whereas the false thumb of the giant panda probably evolved for manipulating bamboo, the false thumbs of the red panda and of S. batalleri more likely evolved as an aid for arboreal locomotion, with the red panda secondarily developing its ability for item manipulation and thus producing one of the most dramatic cases of convergence among vertebrates.

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