The earliest hominin occupation of Europe is one of the most debated topics in palaeoanthropology. However, the purportedly oldest of the Early Pleistocene sites in Eurasia lack precise age control and contain stone tools rather than human fossil remains. Here we report the discovery of a human mandible associated with an assemblage of Mode 1 lithic tools and faunal remains bearing traces of hominin processing, in stratigraphic level TE9 at the site of the Sima del Elefante, Atapuerca, Spain. Level TE9 has been dated to the Early Pleistocene (approximately 1.2-1.1 Myr), based on a combination of palaeomagnetism, cosmogenic nuclides and biostratigraphy. The Sima del Elefante site thus emerges as the oldest, most accurately dated record of human occupation in Europe, to our knowledge. The study of the human mandible suggests that the first settlement of Western Europe could be related to an early demographic expansion out of Africa. The new evidence, with previous findings in other Atapuerca sites (level TD6 from Gran Dolina), also suggests that a speciation event occurred in this extreme area of the Eurasian continent during the Early Pleistocene, initiating the hominin lineage represented by the TE9 and TD6 hominins.

etween 1994 and 1996, during the excavation of a 7-m 2 test pit, a sample of Ϸ100 hominin fossil remains was found in the so-called Aurora Stratum of the stratigraphic unit TD6 of the Gran Dolina site in Sierra de Atapuerca, Burgos, northern Spain (1). The hominin remains were associated with 268 lithic artifacts made of flint, quartzite, sandstone, limestone, and quartz. This sample is characterized by the presence of small artifacts, and includes flakes, denticulates, notches, and side-scrapers and can be characterized as Mode 1 technology (2). The excavation of the Aurora Stratum also yielded a rich small mammal assemblage (26 species, including the water vole Mimomys savini) as well as Ϸ1,000 large mammal fossil remains. The study of the arvicolids suggests that the TD6 level can be referred to the Biharian biochron (3). The macromammal assemblage is biochronologically consistent with the end of the Early Pleistocene or early Cromerian (4, 5). Paleomagnetic dating places TD6 in the Matuyama reversed Chron, hence, before 780 thousand years ago (6, 7). These paleomagnetic data combined with electron spin resonance and uranium series results give an age range of between 780 and 857 thousand years for TD6 (8). Pollen analysis suggests that the Aurora Stratum was deposited under wet, temperate conditions (9); thus, the Aurora Stratum possibly correlates to oxygen isotope stages 21 or 19.In 1997, the TD6 hominins were attributed to Homo antecessor, a new European Lower Pleistocene species (10). On the basis of cranial and dental features, it was suggested that this species could be the common ancestor of modern humans (Homo sapiens) and Neandertals (Homo neanderthalensis). The new taxon was defined in part by using facial and mandibular traits observed in immature individuals. Although the TD6 remains were compared with those of individuals of the same dental age (e.g., KNM-WT 15000), it was clear that the credibility of the species would improve if new specimens corresponding to adult individuals were found. In 2003, we obtained in the Aurora Stratum an excellently preserved mandible, whose description and comparative analysis is the subject of the present study. Mandible ATD6-96Preservation and Age at Death. The specimen catalogued as ATD6-96 was recovered in a planar section of Ͻ1 m 2 , near the area excavated during the 1994-1997 field seasons (1). ATD6-96 is a left half of a gracile mandible of an adult individual (Hominid 7) with the premolars and molars in place (Fig. 1). The specimen is broken at the level of the lateral incisor-canine septum, and the left genial apophysis is preserved. Some postmortem fractures are observed at the region between the corpus and ramus and near the neck of the condyle, but there is no noticeable distortion. Molar (M)3 is fully erupted and exhibits a minimal wear facet at the mesial marginal ridge. During restoration, the corpus and ramus were separated, and the roots of the M3 were observed directly. These roots are at stage Rc of tooth formation (11). Thus, according to mo...

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The Iberian lynx (Lynx pardinus) is the most threatened wild feline in the world. Little is known about the diseases and pathology that affect this animal. The aim of this study was to evaluate the histopathological status of the peripheral lymphoid tissues and thymus of Iberian lynxes necropsied between 1998 and 2003. Seventeen animals including females (n=8) and males (n=9), age range of 10 months to 16 years, with different causes of death were histopathologically and immunohistochemically (anti-CD3, CD79, MAC387, CD68) studied. Feline immunosuppressive virus laboratorial tests were negative. Five individuals presented neoplasia and/or tuberculosis. All animals presented some degree of both B and T cells depletion in peripheral lymphoid tissues and follicular hyalinosis in the center of depleted follicles. A viral origin of the lymphoid depletion is postulated although other causes (inbreeding, stress, toxic) are not ruled out. The loss of the effectiveness of the immune system increases the vulnerability of the critically endangered Iberian lynx to pathogens.