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Living sloths represent two distinct lineages of small-sized mammals that independently evolved arboreality from terrestrial ancestors. The six extant species are the survivors of an evolutionary radiation marked by the extinction of large terrestrial forms at the end of the Quaternary. Until now, sloth evolutionary history has mainly been reconstructed from phylogenetic analyses of morphological characters. Here, we used ancient DNA methods to successfully sequence 10 extinct sloth mitogenomes encompassing all major lineages. This includes the iconic continental ground sloths Megatherium, Megalonyx, Mylodon, and Nothrotheriops and the smaller endemic Caribbean sloths Parocnus and Acratocnus. Phylogenetic analyses identify eight distinct lineages grouped in three well-supported clades, whose interrelationships are markedly incongruent with the currently accepted morphological topology. We show that recently extinct Caribbean sloths have a single origin but comprise two highly divergent lineages that are not directly related to living two-fingered sloths, which instead group with Mylodon. Moreover, living three-fingered sloths do not represent the sister group to all other sloths but are nested within a clade of extinct ground sloths including Megatherium, Megalonyx, and Nothrotheriops. Molecular dating also reveals that the eight newly recognized sloth families all originated between 36 and 28 million years ago (mya). The early divergence of recently extinct Caribbean sloths around 35 mya is consistent with the debated GAARlandia hypothesis postulating the existence at that time of a biogeographic connection between northern South America and the Greater Antilles. This new molecular phylogeny has major implications for reinterpreting sloth morphological evolution, biogeography, and diversification history. Extant sloths are the survivors of an evolutionary radiation marked by the extinction of large terrestrial forms of the Ice Age. By sequencing ten mitogenomes from extinct sloths, Delsuc et al. present a new molecular phylogeny revealing widespread morphological convergence with major implications for reinterpreting sloth evolutionary history. Fil: Delsuc, Frédéric. Université Montpellier II; Francia Fil: Kuch, Melanie. Mcmaster Ancient Dna Centre; Canadá Fil: Gibb, Gillian C.. Massey University; Nueva Zelanda. Université Montpellier II; Francia Fil: Karpinski, Emil. Mcmaster Ancient Dna Centre; Canadá. Mcmaster University; Canadá Fil: Hackenberger, Dirk. Mcmaster Ancient Dna Centre; Canadá Fil: Szpak, Paul. Trent University; Canadá Fil: Martinez, Jorge Gabriel. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; Argentina Fil: Mead, Jim I.. East Tennessee State University; Estados Unidos Fil: McDonald, H. Gregory. Bureau of Land Management; Estados Unidos Fil: Macphee, Ross Douglas Earle. American Museum of Natural History; Estados Unidos Fil: Billet, Guillaume. Université Pierre et Marie Curie; Francia Fil: Hautier, Lionel. Natural History Museum; Reino Unido. Université Montpellier II; Francia Fil: Poinar, Hendrik N.. Mcmaster Ancient Dna Centre; Canadá

International audience; The Glossopteridales are an extinct group of seed plants that dominated Gondwanan floras during the Permian. Their remains are found across a wide range of habitats and paleolatitudes, and it is particularly interesting to understand the anatomical characteristics that might have enabled such an extensive distribution.Here, we document for the first time the bark anatomy of high-latitude glossopteridalean trees using peels and thin sections made from a Late Permian trunk from Skaar Ridge, Antarctica. The bark is 3 cm thick. The secondary phloem is composed of sieve cells, axial and ray parenchyma, and fibers arranged in discontinuous unicellular tangential layers. The outer bark is a rhytidome, with numerous alternating layers of periderm and non-conducting secondary phloem showing some proliferation of the axial parenchyma. Successive periderms mostly run parallel to the cambium, with some longitudinal undulation and rare connections between two periderms. A similar anatomy was observed in bark fragments found isolated in the matrix or closely associated with large glossopterid stems or roots.The anatomy of the Skaar Ridge specimens shows that Antarctic Glossopteridales had a relatively thick, probably stringy bark. The retention of a significant amount of insulating dead bark tissue on the trunk likely provided protection of the cambium, conducting secondary phloem, and potential latent buds against biotic and abiotic environmental hazards (fire, frost, scalding, insects, etc.) and may have contributed to the extensive paleolatitudinal distribution of the Glossopteridales during the Permian.

International audience; We developed a new method to generate topographic maps of tooth crowns from X-ray synchrotron microtomographic data. Maps are drawn after cervix-plane orientation of tooth image stacks, without the need for a geographic information system. Classical topographic maps with contour lines are complemented by slope maps and angularity maps. Cartography allows precise comparisons of cusps morphologies, and quantification of the directions of cusp axis elongation and slope. Application of this method to muroid rodents with cricetine and murine dental patterns reveals clear-cut differences in cusps morphology that are indicative of the direction of the chewing movement, in agreement with wear facet analyses. Rodents with a murine dental pattern were derived from ancestors with a cricetine pattern, and their origin is associated with important changes in cusp morphology and organization. In order to understand such evolutionary change, our investigation is applied to a sample of extant and fossil muroid rodents that are characterized by either a murine dental plan or a cricetine one, or a dental pattern intermediate between those of cricetines and murines.

A new otarionine trilobiteOtarionella rastrumsp. nov., from the late Emsian Mont Peyroux Formation (Montagne Noire, France), is described. Silicified remains, recovered from the underlying Bissounel Formation (early to late Emsian), are also attributed to this new species. These isolated silicified sclerites represent metaprotaspid to young holaspid growth stages, which enables the almost complete ontogeny of an otarionine trilobite with a spinose adult morphology to be described for the first time. Comparison with associated larval and juvenile growth stages ofCyphaspisreveal that the pattern of juvenile cranidial spine distribution inOtarionella rastrumsp. nov. differs from all patterns described so far in the Otarioninae, in particular that characterizing the tribe Otarionini. A second species,Otarionella lkomaliisp. nov., known only from a complete articulated specimen discovered in the early Eifelian of southern Morocco, is also described. Like the middle EifelianOtarionella chamaeleo(Basse, 1997), this new species has only ten thoracic segments, with the fourth and the sixth segments each bearing a long axial spine. In the light of the new elements provided by the ontogenetic sequence ofO. rastrumsp. nov. and the adult specimens of this species andO. lkomaliisp. nov., the putative synonymy ofOtarionellaandOtarionis rejected and a restricted concept of the genusOtarionellais defined.

Four new trace fossils of termites are described from the Upper Miocene and Lower Pliocene continental sandstones of the northern Chad basin. Coatonichnus globosus, ichnogenus and ichnospecies nov. is a large ellipsoidal termite calie (20?40 cm in diameter) more or less flattened at both poles. It is morphologically very similar to the nest of extant termite Hodotermes mossambicus from South Africa. It exhibits an internal shelved pattern of modern Hodotermitidae such as the superposition of flat chambers separated vertically by ramps, columns, walls, and pillars. It is interpreted as the nest of an ancestral species of Hodotermes (Hodotermitidae).The new ichnospecies Vondrichnus planoglobus is composed of dense swarms of tens of chambers connected by a net of straight galleries developed in a single plane. The chambers (5?12 cm in diameter) have a spherical shape with a planar base. Generally, short galleries connect each chamber to the straight main tunnel of meter to decameter-scale length. Vondrichnus planoglobus is interpreted as polychambered diffuse nests of fungus-growing termites (Macrotermitinae, Termitidae). Microfavichnus alveolatus, ichnogenus and ichnospecies nov. is a small-scale alveolar mass (3?8 cm by 2?4 cm). The base of the construction is flat to concave. It is entirely composed of a sub-horizontally layered, alveolar-like structure composed of a regular juxtaposition of millimetre-scale round pellets or balls (mylospheres). Microfavichnus alveolatus is interpreted as fossilized fungus combs of ?fungus-growing? termites (Macrotermitinae, Termitidae). Termitichnus schneideri, ichnospecies nov. is a large-scale extremely flattened construction (15?60 cm in diameter and 6?18 cm in height). The internal shelved pattern is composed of flat chambers separated by columns, walls, and pillars. Each level is connected by ramps. An external wall surrounds the framework constructed. One to several peripheral funnel-shaped tunnels occur sub-perpendicular to the construction. This new Termitichnus ichnospecies is interpreted as being a possible central hive of the Vondrichnus planoglobus net. Fil: Duringer, Philippe. Universite Louis Pasteur; Francia Fil: Schuster, Mathieu. Université de Poitiers; Francia Fil: Genise, Jorge Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Mackaye, Hassan T.. Université de N'Djaména; Chad Fil: Vignaud, Patrick. Université de Poitiers; Francia Fil: Brunet, Michel. Université de Poitiers; Francia

International audience; dagger Siamamia naga, gen. et sp. nov, is described on the basis of three partly articulated skulls and a collection of isolated ossifications from a continental Early Cretaceous Formation of northeastern Thailand. The new taxon is a dagger sinamiid halecomorph as demonstrated by the median parietal and other cranial characters. dagger Sinamiidae is hitherto known by two genera occurring in Early Cretaceous freshwater deposits in China. Although a complete revision of all species within the family is necessary, the Thai material shows characters justifying a new genus. It is the first dagger sinamiid found outside eastern Asia (South and North Chinese blocks, plus small Central Asian terranes), thus validating the close paleogeographical affinities between mainland Asia and SE Asia in the Early Cretaceous. A preliminary phylogenetic assessment of the new taxon with the data matrix of Grande and Bemis (1998) with the addition of data for dagger Siamamia and dagger Tomognathus provides a strict consensus tree similar to the phylogenetic hypothesis of Halecomorphi proposed by these authors, except the basal-most amiids which show a lower resolution in our hypothesis. The dagger Sinamiidae appear as a monophyletic clade, but the four taxa included in the analysis form a polytomy.

International audience; Fossil bone collagen 14C dating and δ13C and δ15N isotopic measurements of the rodent Canariomys bravoi from Tenerife (Canary Islands, Spain) were used to test two different hypotheses about the causes of extinctions of endemic vertebrates on islands, climate versus humans. For the Tenerife giant rat, we show that it survived the climatic change that occurred between the Middle and Late Holocene, but not the settlement of humans on the island.

International audience; An overview of upper pPliocene and Pleistocene otolith assemblages is compiled on the basis of both literature data and newly collected material from several sections located mainly in southern Italy. One hundred and five taxa are listed. Additional comments are provided for taxa subject to discussion. The composition and affinities of the Mediterranean Pleistocene otolith associations (consisting mainly of deep sea fishes) is checked against the available data for Pre-Messinian, Pliocene, and Recent Mediterranean fishes. This analysis is based on the recorded nominal species, but some taxa that could be identified at the generic level only are also included when they are relevant from a biogeographic point of view. Some new data on Piacenzian (middle Pliocene) and Gelasian (upper Pliocene) otoliths are also provided because this time interval still constitutes a major gap in the knowledge of the stratigraphic range of Plio-Pleistocene fish taxa. The Pleistocene deepwater fish fauna of the Mediterranean shows a markedly more oceanic character than the present-day one, a tendency that was all ready observed from early Oligocene till Pliocene times. Starting from the late Piacenzian, an increasing number of Atlantic taxa progressively invaded the Mediterranean including several subpolar and temperate forms. This invasion became stronger in the Gelasian. From this period up to the middle and late Pleistocene, the Mediterranean deepwater fish fauna (mesopelagic and benthopelagic) is enriched by taxa which today are typical for the north Atlantic cold deep water. This faunal shift seems to be correlated with the evolution of the Plio-Pleistocene. Mediterranean paleoceanographic setting as well as with the global climatic deterioration. (c) 2006 Elsevier Masson SAS. All rights reserved.

Editorial material; International audience

The mammalian order Xenarthra (armadillos, anteaters and sloths) is one of the four major clades of placentals, but it remains poorly studied from the molecular phylogenetics perspective. We present here a study encompassing most of the order's diversity in order to establish xenarthrans' intra-ordinal relationships, discuss the evolution of their morphological characters, search for their extant sister group and specify the timing of their radiation with special emphasis on the status of the controversial fossil Eurotamandua. Sequences of three genes (nuclear exon 28 of the Von Willebrand factor and mitochondrial 12S and 16S rRNAs) are compared for eight of the 13 living genera. Phylogenetic analyses confirm the order's monophyly and that of its three major lineages: armadillos (Cingulata), anteaters (Vermilingua) and sloths ('Tardigrada', renamed in 'Folivora'), and our results strongly support the grouping of hairy xenarthrans (anteaters and sloths) into Pilosa. Within placentals, Afrotheria might be the first lineage to branch off, followed by Xenarthra. The morphological adaptative convergence between New World xenarthrans and Old World pangolins is confirmed. Molecular datings place the early emergence of armadillos around the Cretaceous/Tertiary boundary, followed by the divergence between anteaters and sloths in the Early Eocene era. These Tertiary dates contradict the concept of a very ancient origin of modern xenarthran lineages. They also question the placement of the purported fossil anteater (Eurotamandua) from the Middle Eocene period of Europe with the Vermilingua and instead suggest the independent and convergent evolution of this enigmatic taxon.

International audience; The genus Gnetopsis was created for dispersed ovules preserved as compressions showing characteristic long apical expansions and for permineralized cupules (Gnetopsis elliptica) containing similar ovules, both from the late Pennsylvanian of central France. Subsequently, several species, on the basis of isolated ovules preserved as compressions of Mississippian to Pennsylvanian age, have been attributed to the same genus. Reexamination of Renault's original material of Gnetopsis shows that the permineralized ovules of G. elliptica have exceptionally well-preserved integument, nucellus, pollen chamber, and megagametophyte with archegonia. Similarity of the ovules of G. elliptica with those of Conostoma is confirmed, but apical expansions are not known in the last genus. Early Permian dispersed ovules, attributed to Gnetopsis (Gnetopsis augustodunensis), also have been reinvestigated; they are very similar to G. elliptica ovules but devoid of apical expansions and are here transferred to the genus Conostoma. Associated organs of stems assigned to the genus Heterangium are believed to have been produced by the same plant. New reconstructions of the ovule and cupule of G. elliptica are presented, along with an emended diagnosis of G. elliptica. The evolutionary significance of this multiovulate cupule is discussed, considering that G. elliptica is more similar in size and organization to some of the earliest (Devonian-Mississippian) cupules than to the contemporaneous Pennsylvanian uniovulate cupules.

International audience; A new species of permineralised marattialean fern trunk is described from Lopingian (late Permian) aged volcaniclastic tuffs from Panxian County, western Guizhou Province, China and named Psaronius xuii sp. nov. The stem has vascular bundles that are encircled by a bi-layered sheath and has a ground tissue consisting of thicker-walled and thinner-walled parenchymatous cells and dispersed nests of sclerenchymatous cells. Two sclerenchymatous strands occur between neighboring stelar cycles, with this species lacking a peripheral sclerenchyma sheath and possessing a "chrysanthemum"-shaped sclerenchyma strands in the adaxial bay of the peripheral vascular bundles. Although distinct from other species, comparisons demonstrate a consistent organisation amongst contemporaneous species from South Cathaysia that have sclerenchymatous strands in the adaxial bay of the peripheral vascular bundles, vascular bundles and leaf traces surrounded by a vascular bundle sheath, and the middle part of the leaf trace is depressed inward after departing from the peripheral vascular bundle. These features are used to define the Panxianensis Group named after the most comprehensively known species, P. panxianensis. Species within the Panxianensis Group differ from other species from the Carboniferous and Permian floras of Euramerica, Gondwana and North Cathaysia that we place in the Blicklei Group that lack sclerenchymatous strands in the adaxial bay of the peripheral vascular bundles, lack vascular bundle sheaths, and the middle part of the leaf trace is arched outwards when they depart from the peripheral vascular bundles. Members of the Panxianensis Group appear to represent a relatively derived group that appears to be endemic to South Cathaysia, with these presumably evolving from members of the Blicklei Group in the Cisuralian or Guadalupian

International audience; The new vertebrate locality Moissac-IV, in SW France, yields the alligatoroid Diplocynodon sp., the turtle Trionyx sp., and a diversified mammal fauna. The mammal assemblage includes the rodent Protechimys cf. lebratierensis, the artiodactyls Caenomeryx sp., Lophiomeryx chalaniati, Gelocus sp., Metriotherium aff. mirabile, Entelodon sp., and Anthracotherium sp., the perissodactyls Protaceratherium albigense and Eggysodon gaudryi, the carnivore Nimravus intermedius. and the creodonts Hyaenodon dubius and Hyaenodon?leptorhynchus. The Moissac-IV fauna, referred to the MP24 reference level, is both totally distinct from those of Moissac-I (MN1, Earliest Miocene) and Moissac-II (MP29, Late Oligocene) and older than Moissac-III (MP26). It provides original data in a stratified context just prior the Early-Late Oligocene transition, i.e. a stratigraphical interval, which for SW France, was essentially documented by karstic fillings of the Phosphorites of Quercy so far. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

ACL-11-04; International audience; Psaronius housuoensis sp. nov. is described from the Upper Permian Xuanwei Formation deposits of Housuo Coal Mine, Fuyuan County, Yunnan Province, southwest China, adding to the marattialean fern community of the Cathaysian flora. The permineralized stem shows a polycyclic dictyostele with five leaf traces arranged in a helical manner and exhibiting 2/5 phyllotaxy. Vascular bundles arranged in 6 concentric rings with cauline bundles in 5 radial rows. Stem bound externally by a peripheral sclerenchyma sheath. Leaf trace configuration comprised of three vascular bundles resulting from the division of a single originally C-shaped strand. Ground tissue replaced with coprolites and sediments. Stem surrounded by a thick mantle of roots. Occurrence of coprolites within the stem indicates well developed plant-animal interaction during the Late Permian times and that the habitat in which Psaronius grew was abounding with diversity of arthropod or the oribatid mite community preferring the rotting P. housuoensis sp. nov. stem ground tissue as a suitable microenvironment for shelter. Evolutionary pattern of leaf trace development is described in the new species and its possible ecological significance.

International audience; In this paper, we describe four fossil rodent taxa from two new localities situated in the Idam Unit ('Bioturbated Unit) of the Dur At-Talah escarpment in central Libya These rodents belong to the family Phiomyidae (Hys tricognathi) and are distributed amongst three genera (Phiomys, Protophiomys, and Talahphiomys gen. nov.) that include three new species (Phiomys hammudai sp. nov., Protophiomys durattalahensis sp. nov., and Talahphiomys libycus sp. nov.). Although some of these new species are inorphologically close to certain phiomyids from the latest Eocene and Oligocene of the Jebel elQatrani Formation of the Fayum in Egypt, the Idam rodent faunas lack the abundant and somewhat morphologically derived Fayum phiomyids (such as: Metaphiomys, Gaudearnus, Paraphiornys, Phiocricetomys), thereby excluding a similar age for the Dur At-Talah rodent assem blages. More resemblance is shared with the phiomyid (Protophiomys algeriensis) of the Nementcha locality in Algeria, for which a late middle Eocene age is presently admitted. Protophiomys is a primitive representative of the phiomyid African radiation and it is represented at Dur At-Talah by a slightly more derived species (Pr. durattalahensis) than that of Nementcha, thereby suggesting a younger age for Dur AtTalah. As a result, the new rodent assemblages suggest a late middle Eocene age for the Idam ('Bioturhated) deposits of the Dur At-Talah escarpment. This age hypothesis is substantiated by other mammals (especially Proboscidea), which occur in the same sedimentological unit. Interestingly, the dental pattern of Protophiornys and that of Talahphzomys have somewhat stronger affinities with South Asian hystricognath baluchimyines than with Fayum phiomyids. It is clear that haluchimyines and phiomyids have a common ancestry, and that dispersal occurred between Asia and Africa during the middle of the Palaeogene. However, it is not clear if both groups can be strictly separated in two distinct natural groups inasmuch as some haluchimyines (e.g Lophthaluchia, Bugtirnys, Hodsahibia) appear to be phioinyid4ike, and some early members of phiomyids (e.g. Protophiomys, Talahphiomys) are baluchimyine4ike. South Asia and North Africa represent two centres of adaptive radiation of early hystricognathous rodents. The strong dental resemblances between early Asian and African forms are perhaps the result of subsequent convergent evolution after an initial dispersal from Asia, Otherwise, the systematics of these rodents has to be entirely revised, or we must consider that their historical biogeography is much more complex. (C) 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160, 195-213.

Les fouilles entreprises depuis quelques années dans plusieurs gisements du Sud-Est de la France fournissent un aperçu précis de la grande faune de la fin du stade isotopique marin 7 (MIS 7) au début du stade 4. Quatre sites ont des niveaux qui ont été datés de l’Éemien. Ils sont situés pour l’un à l’est du Rhône (Bau de l’Aubesier ; Monieux, Vaucluse - Niveau H), et pour les trois autres à l’ouest de ce fleuve, en Ardèche : grotte de Saint-Marcel d’Ardèche (couche u), abri Moula à Soyons (couches XII à XV) et Baume Flandin à Orgnac-l’Aven. D’après le stade évolutif du tahr (Hemitragus cedrensis) et du cheval (Equus cf. taubachensis), la couche H1 du Bau de l’Aubesier doit être légèrement vieillie (MIS 6). Les trois localités ardéchoises ont livré un assemblage faunique tempéré avec comme éléments communs le daim (Dama sp.), le cerf élaphe (Cervus elaphus), le chevreuil (Capreolus capreolus), le sanglier (Sus scrofa) et chez les carnivores, un ours de type deningeri. Le début du sous-stade 5e (MIS 5e) est caractérisé par la persistance du tahr de la fin du Pléistocène moyen, H. bonali. Il est ensuite relayé par le bouquetin de la lignée du Caucase qui fait sa première apparition en Europe sud-occidentale (Capra caucasica praepyrenaica). La fin du MIS 5e est marquée par l’essor du bouquetin de la lignée alpine (C. ibex), déjà présent sur le territoire depuis la fin du Pléistocène moyen ; son stade évolutif le rattache à la forme du début du Weichselien, C. ibex cebennarum. Les équidés sont représentés par Equus hydruntinus et par un cheval proche d’Equus taubachensis mais néanmoins différent de la forme type des niveaux éemiens de Taubach. Tout au long de l’interglaciaire, les félins sont présents et diversifiés : lion (Panthera (Leo) spelaea), panthère (P. pardus), lynx (Lynx spelaeus) et chat sauvage (Felis silvestris). L’existence du dhole (Cuon alpinus) et de l’ours du Tibet (Ursus thibetanus) est attestée au début du sous-stade 5e. Pour ce dernier, il s’agit de sa dernière mention en Europe. La fin de l’Éemien voit l’apparition de la hyène des cavernes (Crocuta spelaea). Several localities from the Southeast of France were recently excavated. The analyses give a precise view of the great faunal assemblages from the end of the marine isotopic stage 7 (MIS 7) to the beginning of the MIS 4. Four of them are dated to the Eemian. One is located at the Eastern side of the Rhône river (Bau de l’Aubesier; Monieux, Vaucluse - Level H), the three others on its Western side, in Ardèche : Saint-Marcel d’Ardèche cave (Layer u): abri Moula (Soyons- Layers XII to XV) and Baume Flandin (Orgnac-l’Aven). According to the evolutionary stage of the tahr (Hemitragus cedrensis) and the horse (Equus cf. taubachensis), the level H1 of the Bau de l’Aubesier cave is older than previously presumed, dating to the beginning of the MIS6. The three other localities have yielded a temperate association with the following elements in common: fallow deer (Dama sp.), red deer (Cervus elaphus), roe deer (Capreolus capreolus), boar (Sus scrofa) and amongst the Carnivores a bear whose evolutionary stage is consistent with Ursus deningeri. The beginning of the MIS 5e corresponds to the last occurrence of the Middle Pleistocene tahr H. bonali. Thereafter the Caucasian ibex (Capracaucasica praepyrenaica) is observed for the first time in the Southeastern part of the Occidental Europe. At the end of the MIS 5e, the Alpine ibex(C. ibex) inhabits the area. Its evolutionary stage is similar to the C. ibex cebennarum of the early Weichselian. Two Equids are identified: Equus hydruntinus and a horse, close to Equus taubachensis but nevertheless different from the typical one of the Eemian levels of Taubach. Throughout the Eemianperiod, felids are present and diverse: lion (Panthera (Leo) spelaea), leopard (P. pardus), lynx (Lynx spelaeus) and wild cat (Felis silvestris). The dhole(Cuon alpinus) and the Tibetan black bear (U. thibetanus) are present at the beginning of the MIS 5e. It is the last occurrence of the latter in Europe. Theend of the Eemian sees the appearance of the cave hyaena (Crocuta spelaea).

International audience; A sediment core retrieved from Quaternary deposits from the Aammiq wetland (Bekaa Valley, Lebanon) provided a pollen record carrying valuable information which allowed reconstruction of past vegetation dynamics in relation to climate change and anthropogenic impacts. Core stratigraphy and microfossil data helped interpret the depositional settings of the sequence. Before c. 12.2 kyr cal. BP, an expansion of cedars (Cedrus libani) and deciduous oaks (Quercus cerris-type) is observed. The Younger Dryas is marked by the spread of a Chenopodiaceae steppe and a regression of cedars and deciduous oaks. During the early Holocene, an open oak forest expanded concomitantly with the development of a marsh in the Bekaa Valley. Between c. 6.0 and c. 3.4 kyr cal. BP, major disturbances in the sedimentation process are recorded, leading to some dissimilarities with other palaeobotanical records from the Eastern Mediterranean region. After c. 3.4. kyr cal. BP, the pollen data reveal that agriculture in the Bekaa Valley was mainly oriented towards livestock rearing since there is very little record of cultivated plants. In this regard, the results conflict somewhat with other studies carried out in the Eastern Mediterranean region, where intensive cultures have been observed since the early Holocene. Cultures might have been present in other regions in Lebanon but apparently not in this part of the Bekaa Valley.

International audience; During the last two decades, an abundant selachian assemblage has been collected from the late Ypresian (NP12) fossiliferous sands of Premontre (Aisne, northern France) but has received little attention. Sharks of the family Triakidae (Carcharhiniformes) are particularly well represented and all are described and figured herein. Among them, two new species of the genus Galeorhinus are described: G. duchaussoisi sp. nov. and G. louisi sp. nov.; these are compared to the common Paleogene G. ypresiensis which is refigured. Another triakid taxon, the genus Gomphogaleus gen. nov., is described. Most of the triakids have been recorded elsewhere in the North Atlantic region, suggesting a wider distribution than expected for these small sharks during the Paleogene. The present paper updates the list of selachians from Premontre, bringing the number of taxa from 19 to 33 (including 22 sharks and 11 batoids) and improving our knowledge of the ancient North Atlantic Ypresian selachian fauna. Despite this vastly improved record, it is clear that fossil data are still very incomplete and insufficient for calibrating phylogenetic hypotheses of living forms. Review of the Premontre fauna shows that the Triakidae were much more diverse and broadly distributed than at present, suggesting that the limited distribution and low diversity of living forms is probably a recent phenomenon.

International audience; In 1935, Dalinkevičius described and illustrated several teeth of squaloid sharks from Lithuania, originating from deposits considered by him to be of Cenomanian and Turonian age. To date, these strata are known to be of late Albian and late Cenomanian age, respectively. A re-examination of the original collection, together with an analysis of newly collected material, allows these squaloid teeth to be identified as Protosqualus glickmani Averianov, 1997, Squalus sp., Squaliodalatias sp. and Protocentrophorus balticus (Dalinkevičius, 1935) nov. gen., morphologically different from the extant genus Centrophorus. The present material also enables a detailed insight into the first evolutionary stages of deep-sea squaloid sharks, confirmation of the most recent phylogenetic hypotheses regarding extant taxa (e.g., dalatiids being no more derived than other ‘modern-type' squaloid families) and identification of a possible centre of origin of such sharks in Boreal Europe and the Central Asian seaway.

International audience; We report here the results of stable carbon and nitrogen isotope analysis of human and faunal remains from La Vergne (Charente-Maritime, western France), a rare Early Mesolithic burial site (ca. 8500e8000 cal BC). The results for nine humans (average d13C¼19.3&; d15N ¼ 9.4&) indicate a strongly terrestrial diet, dominated by animal protein, with the possibility of, at best, a slight contribution of marinederived protein. Given lower sea-levels in the early Holocene, the site would have been some 60e80 km from the sea at the time of its use; nevertheless, contacts with the coast are shown by the presence of numerous marine shell beads in the graves. In the light of the stable isotope results, it is suggested here that such contacts most likely took the form of exchange with coastal communities whose remains now lie underwater. 2007 Elsevier Ltd. All rights reserved.

International audience; Fossil deep-sea selachians are rare and their diversity underestimated as a consequence of the scarcity of available outcrops of sediments containing them. Here we report a new fossil locality from the Middle Eocene of southwestern France and give a first synthesis of the deep-sea deposits of this area which have yielded one of the richest fossil selachian faunas ever to have inhabited the continental slope. The fossil records of deep-sea sharks and rays are discussed in the context of these new fossil occurrences, a literature review and the recent phylogenetic hypothesis.

(2007). First occurence in Europe of Myocricetodontinae (Rodentia, Gerbillidae) During the lower middle Miocene in the Karstic Locality of Blanquatere 1 (southern France): implications. Journal of Vertebrate Paleontology: Vol. 27, No. 4, pp. 1062-1065.

International audience; Trois espèces du genre Megacricetodon sont reconnues pour la première fois, associées dans un même site, Blanquatère 1 d'âge Miocène, dans le Languedoc-Roussillon. Deux sont nouvelles : M. tautavelensis nov. sp., de petite taille et M. aunayi nov. sp. de taille moyenne à grande, la troisième, M. « collongensis-gersii », de taille moyenne, étant déjà connue dans la région. Les espèces se différencient par leurs dimensions et par la morphologie. Cette découverte souligne la complexité de l'évolution de ce genre en Europe occidentale liée à la différenciation biogéographique et à des phénomènes migratoires. L'âge du gisement est estimé à 16 Ma, à la limite MN 4/MN 5. La position des gisements de Vieux-Collonges (MN 5) et de Sansan (MN 6) est discutée ainsi que l'âge estimé des limites biozonales MN 3/MN 4, MN 4/MN 5 et MN 5/MN 6.

A-07-38; International audience; The genus Eristophyton is founded on woody axes of Mississippian age, showing a dense wood with an araucarioid type of pitting on the radial walls of tracheids and small numerous pits in cross-fields. Distinctive characters of Eristophyton are related to its primary vascular body, especially the structure and arrangement of primary xylem strands, and structure and size of leaf traces. Species described from Permian deposits are not considered in this review, which focuses on the three Mississippian species, E. beinertianum, E. fasciculare, and E. waltonii. Eristophyton consists of plants of arborescent stature that produced a large amount of vascular and cortical secondary tissues, and had their leaves borne on the youngest axes. Anatomical and morphological similarities with Bilignea and Pitus are emphasized. Compared to all other arborescent genera of lignophytic affinities known for the Mississippian, Eristophyton has the widest geographical and stratigraphical extent.

International audience; The human diet was investigated using the carbon and nitrogen isotopic signatures of 93 Mesolithic and Neolithic specimens (not, vert, similar10,000–2000 BC) from the Meuse Basin (Belgium). During the Ancient Mesolithic period (not, vert, similar9300–8000 BC), the environment was generally open and the main dietary protein was provided by hunted terrestrial mammals, with the possible addition of freshwater resources. Human remains are not available in the Meuse Basin from around 8000 BC to 4300 BC, thus preventing the study of the Mesolithic-Neolithic dietary transition in this region. Throughout the Middle Neolithic (not, vert, similar4300–3000 BC), hunting was more difficult and less productive due to a densely forested environment. The contribution of freshwater resources to the diet increased, with the remaining proteins provided by terrestrial wild and/or domestic mammals, indicating that non-agricultural resources were not eliminated in this region during the Middle Neolithic period. The contribution of freshwater resources seems negligible in the Middle/Late and Late Neolithic periods (not, vert, similar3300–1700 BC), with isotopic results revealing a diet composed of agricultural products. The δ15N values of infants are compatible with a weaning age at around 2 years. This study documents the dietary changes that occurred in Belgium during the first part of the Holocene, and reveals the subtle dietary distinction between wild and domestic terrestrial resources and freshwater resources.

International audience; The Middle Miocene climatic cooling (MCC) is a global event recorded synchronously in the marine and continental realms by several geo- and bioindicators around 15–13.5 Ma. The temporal distribution of European plants and ectothermic vertebrates indicates a similar response to the MCC around 15–13.5 Ma. According to the existing correlations of the European mammalian biochronological time scale to the Geomagnetic Polarity Time Scale (GPTS), a cenogram analysis revealed an important reorganisation of the Middle Miocene European terrestrial mammalian faunas that seems to take place later, around 11.5–11 Ma. This discrepancy between the timing of faunal changes can be solved by considering the recent biochronological and magnetostratigraphic data leading to reinterpretations of the debated ages of several Middle Miocene localities that need to be placed before the MCC event. # 2007 Elsevier Masson SAS. All rights reserved.

International audience; Although modern lantern sharks (Etmopteridae, Squaliformes) are taxonomically diverse, their phylogenetic relationships remain unclear. Numerous fossil etmopterids have been recently discovered, and their geologic occurrences are reviewed here. The dentition of the rare recent etmopterid Miroscyllum sheikoi is described. The species shows peculiar ontogenetic changes in the morphology of lower and upper teeth, and allows to assign some fossil material described as Centroscyllium by Ledoux (1972) to Miroscyllium. Moreover, the presence, in Miroscyllium sheikoi, of a morphological transitional dental type between Etmopterus and Centroscyllium, and its discovery in the fossil record allow to propose an alternative way to contribute to the phylogenetic frameworks.

International audience; A biometric analysis of the lower teeth of Recent cow sharks (Hexanchidae) investigates the ontogenetic and phylogenetic aspects of the dental characters employed by many ichthyologists and palaeontologists. The dental characters currently used to separate two extant species of sixgill sharks (Hexanchus griseus and H. nakamurai) are analysed and the fossil record of their relatives reviewed. The main results suggest that the cusp number ratio (number of cusps per mm) is preferable to width of the lower tooth for inference of total body size, at least in species of Hexanchus. The presence of a serrated edge or an enlarged acrocone appears to depend on ontogeny and care must be taken when using these as taxomomic characters. Three Eocene species of Hexanchus, H. collinsonae, H. hookeri, and H. agassizi, and a new assemblage of fossil teeth from the late Ypresian/early Lutetian (Early/Middle Eocene) of south-western France, are also analysed. The first two of these species may be ontogenetic states of H. agassizi. Hexanchus agassizi, belonging to the vituliform lineage and closely related to the living H. nakamurai, is considered here to be the only species of Hexanchus in the Lower to Middle Eocene. A brief overview of Palaeogene Hexanchus, suggests no evidence of the grisiform group (closely related to living H. griseus) before the Late Eocene.

International audience; A new species of trilobite, Cyrtosymbole rectifrons, from Famennian marlstones in the south-eastern vicinity of Erfoud (Tafilalt, Morocco), is described. Silicified sclerites of various sizes allow the description of its late growth sequence, which demonstrates that some characteristic features of the Cyrtosymbolinae are acquired during late ontogeny. Precise examination of exceptionally well-preserved material enables reconstruction of the in situ position of the adult hypostome, together with a reconsideration of its relation to the dorsal exoskeleton and its morphofunctional capacity for movement. The natant hypostomal condition inferred for C. rectifrons suggests that it is not always possible to deduce the nature of hypostomal attachment from the dorsal morphology alone.

International audience; Two new species of scutelluine styginid trilobites are described from Frasnian strata in the Virgin Hills Formation in the Canning Basin of Western Australia. They are placed in the genus Telopeltis n. gen., reflecting the fact that their final occurrence in the late Frasnian, up to the latest Frasnian Kellwasser extinction event, is the last known record of scutelluine trilobites. As such, it also represents the youngest record of the order Corynexochida. The two species, Telopeltis woodwardi n. sp. and Telopeltis microphthalmus n. sp., are unlike most other scutelluines in possessing extremely vaulted pygidia and showing trends to eye reduction. Such eye reduction is a common feature of late Frasnian trilobites. The characteristic morphological features of this small genus are indicative of evolution of this last scutelluine by paedomorphosis.

New dental and postcranial remains of the alleged louisinine hyopsodontid “condylarth” Microhyus from the European Paleocene/Eocene transition are described, and prompt a reevaluation of the genus. New specimens belonging to Microhyus musculus from Dormaal (MP7, Belgium ) provide the first evidence of the lower dentition of the type species. We describe M. musculus? from Pourcy (MP7, France) and cf. Microhyus sp. from Berru (MP6a, France). A rich original assemblage of M. reisi from Silveirinha (MP7, Portugal ) allows a detailed description of the morphological dental variation within that species. Well-preserved astragali and calcanei from Silveirinha can be confidently attributed to Microhyus reisi. Functional analysis of these elements suggests that Microhyus was a terrestrial mammal capable of rapid running or jumping. The pedal morphology of Microhyus is very similar to that of Paschatherium. These louisinines share some derived characters with the hyopsodontids Apheliscus and Haplomylus (e.g., the occurrence of a cotylar fossa on the astragalus) but they differ from Hyopsodus. Therefore, in view of the pedal morphology alone, the hyopsodontids may be polyphyletic. Given the dental similarities between Microhyus and the early representatives of the order Macroscelidea, we compared the tarsal morphology of louisinines with that of modern macroscelidids (Paleogene tarsal remains are currently unknown for this group). Macroscelidids and louisinines present some similarities in their astragalar morphology; however, the macroscelidid astragalus appears to be too specialized to be compared with that of Microhyus and Paschatherium.

International audience; The subsistence patterns of Iron Age and Historical period humans from south-western Turkmenistan have been reconstructed using the carbon and nitrogen isotopic compositions of archaeological faunal and human bones. A qualitative comparison of the isotopic signatures points to a small proportion of ruminant meat and dairy in human diet for both periods. The ranges of proportions of dietary items yielded by a quantitative approach based on concentration dependent mixing models confirm the high proportions of plant food in the average diet, and show little change in the reconstructed diet for both periods. A comparison of results from zooarchaeological and isotopic approaches illustrates their complementarity in subsistence patterns reconstruction.

International audience; The discovery of a new elasmobranch assemblage from the Lower Cretaceous of Thailand allows expansion of the faunal list and refinement of our knowledge of the dental morphological features of some previously described taxa. The root morphology of Thaiodus is now known and a more complete description of the dentition of the genus Heteroptychodus, known formerly by a single tooth from Japan, is given. A new genus and species, Acrorhizodus khoratensis, characterized by teeth of very special morphology is described. Besides these taxa, some teeth of a genus probably close to Hybodus, but with more bulbous teeth, are present. Owing to the sedimentological characters of the deposits and the associated fauna (dinosaurs), it is probable that this elasmobranch fauna lived in a freshwater or brackish environment. The simultaneous occurrence of teeth of Heteroptychodus in Thailand and Japan favours the existence of a large continental area in south-east Asia during the Early Cretaceous.

International audience; The mammal bearing locality Blanquatere 1 delivers the highest diversified glirid fauna of middle Miocene age (near MN 4/MN 5 boundary) discovered up to now in southern Europe: nine genera and 16 species. Three species are new: Prodryomys remmerti n. sp., a large-sized species with only a few accessory crests, Glirudinus intermedius n. sp., intermediate in size and shape between G. minutus and G. modestus and Glirudinus magnus n. sp., the largest species of the genus presently known; the two former and the genus Muscardinus are possible migrants. Remarks are made about the phylogeny of Glirudinus and Prodyromys, and the stratigraphic distribution of Vasseuromys species must be extended. The overall fauna of glirids suggests a significant forest cover.

International audience; A magnetostrati graphic study was performed on continental Upper Cretaceous beds in the L'Olivet quarry, Villeveyrac-Meze Basin (Herault, France). Nearly all specimens subjected to progressive thermal demagnetization procedures exhibit opposite polarities for the low- and high-temperature magnetization components. The high-temperature component shows reverse polarity, characteristic of the Late Cretaceous magnetization, which is well isolated between 200 degrees and 450 degrees C. The overall mean paleomagnetic direction (incl. = -39.1 degrees, decl. = 160.7 degrees, k = 15, a(95) = 10) suggests a counterclockwise vertical axis rotation of about 15.1 degrees +/- 8.3 with respect to the expected Late Cretaceous direction calculated from the Eurasian polar wander curve (incl. = -49.0 degrees, decl. = 174 degrees). Combined with local biostratigraphic data, the L'Olivet sequence can be correlated with polarity chron C33.lr, corresponding to the Early Campanian with an age of 83.5 to 79.5 Ma.

Numerous silicified and calcareous sclerites of various sizes, recovered from the latest Famennian of Thuringia (Germany), allow the description of the first complete growth series of a blind proetoid trilobite: Drevermannia richteri. In addition, the partial ontogenetic development of Drevermannia antecurvata sp. nov. and undetermined species, Drevermannia sp. 1, are described. The proetoid anaprotaspides, associated with D. richteri, illustrate that a marked increase in larval size occurred prior to the terminal Devonian extinction event. Considering the homogeneity of larval size in older Devonian proetoids, it is interpreted as evidence that the developmental strategy of these trilobites was significantly modified. Though largely speculative, two alternative hypotheses are proposed to explain this modification. Finally, all three ontogenetic sequences show that ocular structures never develop externally in Drevermannia, but also illustrate that the development of optical nerves is not completely lost in this group. This suggests that blindness in the Drevermannia lineage followed a centripetal mode of eye reduction.

Among rodents, the lineage from Progonomys hispanicus to Stephanomys documents a case of increasing size and dental specialization during an approximately 9 Myr time-interval. On the contrary, some contemporaneous generalist lineages like Apodemus show a limited morphological evolution. Dental shape can be related to diet and can be used to assess the ecological changes along the lineages. Consequently, size and shape of the first upper molar were measured in order to quantify the patterns of morphological evolution along both lineages and compare them to environmental trends. Climatic changes do not have a direct influence on evolution, but they open new ecological opportunities by changing vegetation and allow the evolution of a specialist like Stephanomys . On the other hand, environmental changes are not dramatic enough to destroy the habitat of a long-term generalist like Apodemus . Hence, our results exemplify a case of an influence of climate on the evolution of specialist species, although a generalist species may persist without change.

International audience; The use of nucleotide and amino acid sequences allows improved understanding of the timing of evolutionary events of life on earth. Molecular estimates of divergence times are, however, controversial and are generally much more ancient than suggested by the fossil record. The limited number of genes and species explored and pervasive variations in evolutionary rates are the most likely sources of such discrepancies. Here we compared concatenated amino acid sequences of 129 proteins from 36 eukaryotes to determine the divergence times of several major clades, including animals, fungi, plants, and various protists. Due to significant variations in their evolutionary rates, and to handle the uncertainty of the fossil record, we used a Bayesian relaxed molecular clock simultaneously calibrated by six paleontological constraints. We show that, according to 95% credibility intervals, the eukaryotic kingdoms diversified 950-1,259 million years ago (Mya), animals diverged from choanoflagellates 761-957 Mya, and the debated age of the split between protostomes and deuterostomes occurred 642-761 Mya. The divergence times appeared to be robust with respect to prior assumptions and paleontological calibrations. Interestingly, these relaxed clock time estimates are much more recent than those obtained under the assumption of a global molecular clock, yet bilaterian diversification appears to be approximately 100 million years more ancient than the Cambrian boundary.