1,721,042 research outputs found

    Early Oligocene fish otoliths from the Castellane area (SE France) and an overview of Mediterranean teleost faunas at the Eocene-Oligocene boundary

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    The study of Oligocene fish otoliths from the blue marls in the Castellane area allowed the reconstruction of a teleost fauna of 38 taxa of which 16 could be identified at species level. This is the first otolith-based neritic fish fauna known from the Mediterranean Early Oligocene. Additional data for Early Oligocene otolith-based fish faunas of the paleo-Mediterranean Basin are available only from the Liguro-Piemontese Basin, northern Italy, where the associations are dominated by deepwater fishes. Combining the data from both Mediterranean paleoenvironments, one obtains a list of 88 taxa of which 48 could be identified to species level. This is the only available overview on the composition of the otolith-based fish fauna in the Mediterranean realm during the Early Oligocene. It is shown that already in the Oligocene, the neritic fauna shows good affinities with the present-day Mediterranean one, while the deepwater fauna was a circumglobal oceanic one, strongly different from the Recent Mediterranean deepwater fauna. The Early Oligocene and Late Eocene Mediterranean otolith-based teleost faunas are compared to each other and to contemporaneous faunas from the Aquitaine Basin. This provides evidence for a very strong faunal break in both basins, both in the neritic and the mesopelagic fauna, and this faunal turnover is interpreted as a response to the paleoceanographic and climatic changes (cooling) that took place at the Late Eocene-Early Oligocene at global scale. Finally, the results indicate the great homogeneity of the Eastern Atlantic and Mediterranean faunas during the late Eocene. Notwithstanding the strong faunal turnover at the Eocene-Oligocene boundary, the new Oligocene fauna also exhibits a similar homogeneity over a large geographic area which, for this time unit, can be extended to the Paratethys

    Lampadena ionica: a new teleost from the Mediterranean Pleistocene

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    The new species Lampadena ionica (Myctophidae, Teleostei) is described from lower and middle Pleistocene deposits of southern Italy. In particular, L. ionica is known from the "large Gephyrocapsa" up to the Pseudoemiliania lacunosa biozone. Apparently, the species became extinct before the end of the Pleistocene. Although the genus Lampadena lives only outside the Mediterranean today, it is known from the Mediterranean realm since the early Miocene. L. ionica seems to be the only species of the genus Lampadena existing in the Pleistocene deposits of the Mediterranean area. The new species has been found only associated with benthic faunas (invertebrate and vertebrate) indicating an bathyal environment deeper than 500m

    Fish otoliths from the Priabonian (Late Eocene) of North Italy and South-East France - Their palaeobiogeographical significance

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    The study of the Late Eocene (Priabonian) otolith associations from Possagno, North-East Italy, and from the Synclinal d’Allons in Haute Provence, South-East France, allows for the reconstruction of a teleost fauna of 55 taxa, which is the most diversified assemblage presently known from the Upper Eocene Paleo–Mediterranean basin. Thirty-six taxa are identified at the species level, and five of those are new: “genus Alepocephalidarum” astrictus, “genus Lophiiformorum” canovae, “genus Agonidarum” sudans, “genus Uranoscopidarum” cochlearis and Aseraggodes laganum. In the Synclinal d’Allons, the otolith associations reflect a tropical to subtropical neritic environment with a few mesopelagic fishes. At Possagno, the associations indicate an environment that changed from one that was deep and exposed to the pelagic realm and then evolved to a more shallow sea with a well-diversified benthic life and less mesopelagic fishes. A paleobiogeographical analysis of all known data on Priabonian otoliths, worldwide, shows clearly a western Atlantic (Louisiana) and an eastern Atlantic–Paleomediterranean association. In the eastern Atlantic–Paleomediterranean association, the Aquitaine association not only differs from the Possagno–Allons association in function of its more distant geographical position, but also by its stronger oceanic character in the southern part of the basin, and by the occurrence in the north, of a very shallow water facies (Saint-Estephe Formation) that contains some taxa which are known nowhere else in the Priabonian. The Ukraine fauna is characterized by a high number of species, which have an Oligocene record in other European sites. The northern geographic location of Ukraine, combined with the good connections to both the North Sea Basin and the Turgai street can provide the explanation. Many Oligocene species (or their close relatives) probably already existed at Eocene times in more northern regions, but could penetrate only in more southern European seas since the strong cooling at the beginning of the Oligocene

    Fish otoliths from the pre-evaporitic (Early Messinian) sediments of northern Italy: their stratigraphic and palaeobiogeographic significance

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    The study of otolith assemblages from the preevaporitic Messinian deposits allows the reconstruction of a fauna of 79 taxa of which 35 could be identiWed at the speciWc level. Three of these are new: Diaphus rubus, Myctophum coppa, and Uranoscopus ciabatta. The assemblages reXect mainly a neritic environment inXuenced by the oceanic realm. Analysis of the global present-day geographic distribution of 42 of the recognised Messinian genera indicates that 88% of these are still living in the Mediterranean, 98% in the Atlantic and 78% in the Indo-PaciWc realm. These results are in good agreement with the evolutionary trends documented for the Oligocene and Miocene teleost fauna, speciWcally an increase in percentage of genera inhabiting the modern Mediterranean, a very high percentage of Atlantic and Indo-PaciWc genera, and a slight fall of the importance of present-day Indo-PaciWc genera from the Rupelian up to the Late Miocene. Analysing the composition of the Early Messinian fauna at the level of nominal species indicates that about 53% of the species represented in the assemblages are still living in the Recent Mediterranean, and that a signiWcant number of these were already present in the Tortonian. It is interesting that these species are mainly neritic. This seems to conWrm that the close aYnity of the fossil assemblage with the present-day Mediterranean neritic fauna, which was already recorded at the genus level for the Rupelian fauna, persists during the Neogene and continues until the Pleistocene

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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