Devonian antiarch placoderms from Belgium revisited

peer reviewedAnatomical, systematic, and paleobiogeographical data on the Devonian antiarchs from Belgium are reviewed, updated and completed thanks to new data from the field and re-examination of paleontological collections. The material of Bothriolepis lohesti is enhanced and the species redescribed in more detail. An undetermined species of Bothriolepis is recorded from the Famennian of Modave (Liège Province), one species of Asterolepis redescribed from the Givetian of Hingeon and another one described from the Givetian of Mazy (Namur Province). Grossilepis rikiki sp. nov. is recorded from the Famennian tetrapod-bearing locality of Strud (Namur Province) and from the Famennian of Moresnet (Liège Province). It is the first occurrence of Grossilepis after the Frasnian and on the central southern coast of the Euramerican continent. Its occurrence in the Famennian of Belgium may be the result of a late arrival from the Moscow Platform and the Baltic Depression, where the genus is known from Frasnian deposits. Remigolepis durnalensis sp. nov. is described from the Famennian of Spontin near Durnal (Namur Province). Except for the doubtful occurrence of Remigolepis sp. in Scotland, this is the first record of this genus in Western Europe. Its occurrence in Belgium reinforces the strong faunal affinities between Belgium and East Greenland and the hypothesis of a hydrographical link between the two areas during the Late Devonian

Devonian and Carboniferous dendroid graptolites from Belgium and their significance for the taxonomy of the Dendroidea

peer reviewedDevonian and Carboniferous dendroid graptolites from Belgium are evaluated and partly revised. New finds in two different stratigraphic intervals of the ‘Carrière de Lompret’, an active quarry exploiting Frasnian limestones and shales east of Frasnes-lez-Couvin, allow the identification of Callograptus sp. and Dictyonema fraiponti, both belonging to the dendroid family Acanthograptidae. The relatively high diversity of the dendroid graptolite fauna from the Viséan Marbre noir de Denée, one of the few Carboniferous graptolite faunas in the world, can be shown to be based on astogenetic and preservational aspects. Nearly all known specimens can be included in the highly variable Dictyonema fraiponti, a fan-shaped large dendroid species with complex stipes formed from tubular thecae, possessing simple to complex bridges connecting adjacent stipes. Some of the graptolite material is well preserved and provides important information on the tubarium construction of Devonian to Carboniferous dendroid graptolites and, thus, is highly significant for a taxonomic and phylogenetic understanding of the youngest dendroid graptolite faunas worldwide. The genera Callograptus and Ptiograptus are revised based on their type species (Callograptus elegans from Quebec, Canada; Ptiograptus percorrugatus from the Silurian or Devonian of Kentucky, USA) and referred to the Acanthograptidae

The origins and spread of domestic horses from the Western Eurasian steppes

This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: All collapsed and paired-end sequence data for samples sequenced in this study are available in compressed fastq format through the European Nucleotide Archive under accession number PRJEB44430, together with rescaled and trimmed bam sequence alignments against both the nuclear and mitochondrial horse reference genomes. Previously published ancient data used in this study are available under accession numbers PRJEB7537, PRJEB10098, PRJEB10854, PRJEB22390 and PRJEB31613, and detailed in Supplementary Table 1. The genomes of ten modern horses, publicly available, were also accessed as indicated in their corresponding original publications57,61,85-87.NOTE: see the published version available via the DOI in this record for the full list of authorsDomestication of horses fundamentally transformed long-range mobility and warfare. However, modern domesticated breeds do not descend from the earliest domestic horse lineage associated with archaeological evidence of bridling, milking and corralling at Botai, Central Asia around 3500 BC. Other longstanding candidate regions for horse domestication, such as Iberia and Anatolia, have also recently been challenged. Thus, the genetic, geographic and temporal origins of modern domestic horses have remained unknown. Here we pinpoint the Western Eurasian steppes, especially the lower Volga-Don region, as the homeland of modern domestic horses. Furthermore, we map the population changes accompanying domestication from 273 ancient horse genomes. This reveals that modern domestic horses ultimately replaced almost all other local populations as they expanded rapidly across Eurasia from about 2000 BC, synchronously with equestrian material culture, including Sintashta spoke-wheeled chariots. We find that equestrianism involved strong selection for critical locomotor and behavioural adaptations at the GSDMC and ZFPM1 genes. Our results reject the commonly held association between horseback riding and the massive expansion of Yamnaya steppe pastoralists into Europe around 3000 BC driving the spread of Indo-European languages. This contrasts with the scenario in Asia where Indo-Iranian languages, chariots and horses spread together, following the early second millennium BC Sintashta culture

Analyse de l'eau du Poncia (Gembloux)

L'abstract ainsi que le poster peuvent être obtenus sur demande.<BR> Le poster peut être obtenu sur https://www.researchgate.net/profile/Gilles_Olive/contributions/?ev=prf_act ou bien sur http://orbi.ulg.ac.be/browse?type=authorulg&rpp=20&value=Olive%2C+Gilles+p079922International audienceLe Poncia est un cours d'eau situé sur le "village" de Grand-Manil (Gembloux, Belgique). Dans le cadre de sa réhabilitation, huit paramètres (température, pH, conductivité, concentration en ions ammonium, concentration en ions nitrite, concentration en ions nitrate, concentration en ions phosphate et concentration en oxygène dissous) ont été étudiés sur 20 mois. Nous présentons ici les résultats de ces 20 mois d'analyse.<BR> *** L'abstract ainsi que le poster peuvent être obtenus sur demande. ***<BR>Le poster peut être obtenu sur https://www.researchgate.net/profile/Gilles_Olive/contributions/?ev=prf_act ou bien sur http://orbi.ulg.ac.be/browse?type=authorulg&rpp=20&value=Olive%2C+Gilles+p07992

A new placoderm fish (Acanthothoraci) from the Early Devonian Jauf Formation (Saudi Arabia)

peer reviewedAn exceptionally well-preserved new acanthothoracid (placoderm fish) presenting complete endocranium and skull roof, from Saudi Arabia (Qasr Limestone Member, Jauf Formation), Early Devonian in age, is described as Arabosteus variabilis n. gen. n. sp. Compared to other Acanthothoraci, the new taxon exhibits a skull roof variable in its dermal plate distribution (e.g. a supernumerary plate: the posterior central plate) and sensory line pattern. Even the different specimens of this taxon show such variability between them. Arabosteus variabilis enlarges the scope of our knowledge of Acanthothoraci and Placodermi in general. Traditionally, the Arthrodira, one of the historically earliest described groups, provide the standard reference model for the placoderm skull roof pattern. The interpretation of the acanthothoracid skull roof pattern of the Saudi taxon from an arthrodiran model and the establishment of homologies is impossible to resolve unless based on prior assumptions (e.g. hypothesis of fragmentation or fusion for the paranuchal plate complex). The lateral line system of A. variabilis is unstable (e.g. presence or absence of the postmarginal sensory line canal) making it ambiguous to define bone homology and terminology. Consequently spatial distribution of skull roof plates has been retained for such a task with a minimal reference to the instable features of the sensory line groove distribution

"Ca ne va pas de soi" (Le masculin, le féminin et le sujet)

Lacan considérait le genre comme une entité grammaticale, il lui a préféré la sexuation, qui nomme le processus complexe (et qui ne se réduit pas à des identifications) par lequel un sujet devient (ou pas) homme ou femme. Le choix, pour un sujet, d'être homme ou femme s'enracine dans ses modes de jouissance, jouissance phallique et/ou jouissance Autre. Lacan développe, en particulier dans le séminaire Encore , le manque d'un signifiant pour dire La femme ( La femme n'existe pas ), et l'impossible écriture du rapport sexuel ( il n'y a pas de rapport sexuel ). Pour un sujet névrosé, la sexuation s'appuie très tôt sur la fonction phallique. La névrose recouvre ce choix par des identifications qui le voilent, le contrarient: identifications viriles de la femme hystérique, identification à la mère du névrosé obsessionnel. Malgré cette ambiguïté apparente, le choix semble souvent définitif. L'inscription dans la foncttion phallique donne une certaine inertie au choix infantile de la sexuation. Il y a symptômes sexuels mais la sexuation est stable. Le sujet psychotique affiche, lui, une conviction sans faille, qui semble balayer toutes les interrogations du sujet, La transsexualisme en est le paradigme, un choix inébranlable. Cependant avant d'inventer un signifiant autre que phallique pour la jouissance, il y a une période de perplexité concernant son sexe propre et celui du partenaire. L'ambiguïté est également à son comble dans les moments féconds: la chute des identifications laisse le sujet horsexe , ni homme ni femme (ou les deux en même temps).Les questions du sujet, quelle que soit sa structure et son sexe biologique, sont nombreuses en ce qui concerne cette problématique qu'est la sexuation. Comment être une femme? En étant mère? Ou sur le modèle de Médée, la vraie femme ? Le sujet hystérique s'interroge. Suis-je homme ou femme? Parfois se revêtir de semblant paraît plus commode, c'est l'exemple de la mascarade, qui consiste à faire croire qu'on n'a pas le phallus, parce qu'on pense qu'on l'a (alors qu'en fait on ne l'a pas).RENNES1-BU Santé (352382103) / SudocSudocFranceF