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RESTAURO DI UN REPERTO CON RESTI DI TARTARUGA DEL MIOCENE SUPERIORE DEL BACINO DI BACCINELLO-CINIGIANO (GROSSETO)
No full textTra la scoperta di un fossile in campagna e la sua disponibilità per la comunità scientifica o per la fruizione del pubblico con l’esposizione all’interno di un museo, è necessario un passaggio fondamentale, che è quello di preparazione e restauro in laboratorio.
Questa comunicazione presenta gli interventi che hanno permesso il restauro di un reperto contenente resti appartenenti a uno o più esemplari di tartaruga rinvenuti nei pressi di Baccinello, in provincia di Grosseto.
Il fossile è stato recuperato dal bacino neoautoctono di Baccinello-Cinigiano, in sedimenti che hanno restituito la associazione faunistica detta V0 (Engesser 1983) e affioranti lungo il Fosso della Fittaia. Questa parte della successione è riferita al Miocene superiore, (MN 11, Turoliano; Engesser 1983, 1989). Insieme ai resti di vertebrati erano presenti anche gusci di molluschi d’acqua dolce che, insieme ai dati sedimentologici (Benvenuti et al. 2001) forniscono indicazione sul contesto di deposizione del sedimento inglobante in ambiente lacustre.
Il reperto analizzato è incluso in un sedimento composto da argille in una matrice marnosa, più tenace alla rottura rispetto alle prime. L’analisi mineralogica del sedimento ha evidenziato la presenza di Quarzo (SiO2), Calcite (CaCO3) ed Oligonite [Fe(Mn,Zn)(CO3)2]; con la stessa analisi diffrattometrica effettuata in un campione del fossile, sono stati individuati Quarzo (SiO2), Goetite (Fe2O3·H2O), Calcite (CaCO3), Oligonite [Fe(Mn,Zn)(CO3)2] e Fluorapatite [Ca5(PO4)3F]. Questi risultati indicano che esiste una certa uniformità tra la roccia inglobante e i resti fossili.
A prima vista, i frammenti di ossa e delle placche del piastrone erano disposti su piani diversi, e solo in alcuni punti era possibile vedere una precisa connessione anatomica tra i vari elementi.
Inizialmente, il reperto si presentava scomposto in più parti e come prima fase queste sono state ricollocate nella posizione originale. Dopodiché, siamo passati a liberare i resti fossili dalla roccia inglobante grazie all’uso di un vibroincisore. Tale strumento, utilizzando una sorgente di aria compressa che genera delle vibrazioni, consente di eliminare il sedimento intorno alle ossa senza danneggiarle.
Infine, sono stati eseguiti alcuni stucchi nelle fratture preesistenti all’interno del reperto per ottenere una migliore lettura e uniformità della superficie utilizzando un consolidante reversibile (Mowilith) impastato con la roccia di appartenenza al sedimento, così da ottenere un effetto cromatico simile all’originale. Come ultimo passo del procedimento, è stato effettuato un consolidamento di tutti i resti e una pulitura delle superfici per valorizzare il risultato finale del restauro.
In questo lavoro di restauro sono state tenute presenti due principali finalità:
- quella scientifica, per raggiungere la migliore condizione possibile del reperto in modo da
consentire lo studio paleontologico;
- quella estetica, volta al migliore apprezzamento e facile lettura da parte del pubblico
NEW DATA FROM BACCINELLO V0 (GROSSETO, TUSCANY), THE OLDEST ASSEMBLAGE OF THE ENDEMIC TUSCO-SARDINIAN LATE MIOCENE VERTEBRATE FAUNA.
No full textThe Late Miocene endemic vertebrate assemblage of Baccinello V0 is the oldest vertebrate fauna within the Baccinello-Cinigiano basin succession in southern Tuscany (Benvenuti et al., 2001; Rook et al, 2011). The BC Basin is celebrated for recording vertebrate assemblages that yielded the youngest European Miocene Hominoid, Oreopithecus bambolii (Casanovas Villar et al., 2011). The faunal assemblages are known and described since 1960’s (de Terra, 1954; Lorenz,1968; Hurzeler & Engesser, 1976).
The so-called V0 assemblage, mainly made up by small mammals, was discovered by researchers of the Basel Naturhistorisches Museum and partially described by Engesser (1989), who described the murid remains. According to the latter author the Bacciello V0 faunal list includes: Huerzelerimys vireti, Anthracoglis marinoi, Paludotona sp., Chiroptera indet., Soricidae indet., and Tyrrhenotragus sp.
A reconnaissance along the Trasubbie river by the authors was made in June-July 2013 within the framework of a project aiming to acquire a better knowledge of the geology of the BC Basin and the vertebrate fossil record of the Late Miocene of southern Tuscany. The exposure conditions allowed us to investigate the sedimentary succession outcropping along the small creek Fosso della Fittaia and to individuate the V0 fossiliferous level that was intensely sampled for screen washing.
The sample yielded a number of fossil remains that will allow improving our documentation of the Baccinello V0 assemblage. In addition to the already recognized Huerzelerimys vireti, and Anthracoglis marinoi, a few dental remains permit identifying the occurrence of a giant dormouse (possibly Gliridae nov. gen. et nov. sp. from Baccinello V1 described by Engesser in 1983). Worth noting the occurrence in the new sample of two mandibles of Soricidae indet., as well as of several elements of the Herpetofauna (Anura indet., Lacertidae indet., Anguidae indet., Serpentes indet., Testudinae indet)
Preliminary report on the taxonomic revision of Fossil Equidae from Tizi’n Tadderht (Ouarzazate, Morocco)
Full text linkWe are reviewing the sample of fossil Equidae, belon-ging to the genus “Hipparion” s.s. (see Armour-Chelu & Bernor, 2011) from Tizi’n Tadderht (Ouarzazate, Morocco), a fossiliferous site chronologically referable to the Late Miocene.The fossiliferous locality of Tizi’n Tadderht, already known in the literature (Geraads et al., 2012; Zouhri et al., 2012), has yielded a small but significant vertebrate fossil association. It represents the first documentation of a Late Miocene vertebrate fauna in the western area of North Africa. This new fauna allows to expand the possibilities of investigation on the biogeographical and evolutionary record of the vertebrate fossils in the circum-Mediterranean are
Vertebrate records
No full textThis chapter introduces the beginning of Pleistocene vertebrate records, starting from an overview of the Plio-Pleistocene transition. Understanding the Early Pleistocene vertebrate record is impossible without the knowledge of the events characterizing the setting of Early Pleistocene land vertebrate communities. A number of taxa are selected to describe evolutionary and dispersal patterns within the Early Pleistocene. These are the dispersals and evolutionary history of Canidae, elephants, horses, Rhinocerotidae, Hippopotamidae and Cervidae. The last section offers an overview of the Early Pleistocene herpetofauna
Evolution of Early Equus in Italy, Georgia, the Indian Subcontinent, East Africa, and the Origins of African Zebras
Full text linkWe report here ecological and morphological characterization of the main Old World Equus in North America, Asia, Europe, and Africa, by comparing the studied fossil forms with the living Equus grevyi zebra. Equus simplicidens from North America, Equus livenzovenzis, Equus stenonis, and Equus stehlini from Italy, Equus sivalensis from India, Equus cf. stenonis and a small Equus from Georgia (Caucasus), Equus oldowayensis, Equus koobiforensis, and Equus cf. tabeti from Kenya and the extant Equus grevyi are described in their cranial and dental features and are compared in morphological postcranial dimensions by means of log10 ratio analysis. The occurrence of the two horses at the Dmanisi Homo site in Georgia is reported here for the first time. Our comparative analyses allow to confirm the primitive lineage of the ancient zebras as derived from Equus simplicidens, and the successive evolution of the stenonine horses in Asia, South Asia, and Europe during the Plio-Pleistocene. The morphological analysis has reveals a clear trend in third metacarpals and third metatarsals of E. simpicidens, the small Equus from Dmanisi and E. grevyi, suggesting a close relationship between these species. The trend of the stenonine Equus from Europe and Asia confirms the possible derivation from the North America Equus simplicidens. The description of all the Old World Equus is integrated with an overview of their paleoecological context, with a referred section for each locality where these fossils were found. This contribution represents a comprehensive review of the present knowledge of the Old World Equus evolutionary history, with some new important data in deciphering the deep origin and evolution of ancient and living zebras
Testing Equid Body Mass Estimate Equations on Modern Zebras-With Implications to Understanding the Relationship of Body Size, Diet, and Habitats of Equus in the Pleistocene of Europe
Full text linkThe monodactyl horses of the genus Equus originated in North America during the Pliocene, and from the beginning of the Pleistocene, they have been an essential part of the large ungulate communities of Europe, North America and Africa. Understanding how body size of Equus species evolved and varied in relation to changes in environments and diet thus forms an important part of understanding the dynamics of ungulate body size variation in relation to Pleistocene paleoenvironmental changes. Here we test previously published body mass estimation equations for the family Equidae by investigating how accurately different skeletal and dental measurements estimate the mean body mass (and body mass range) reported for extant Grevy's zebra (Equus grevyi) and Burchell's zebra (Equus quagga). Based on these tests and information on how frequently skeletal elements occur in the fossil record, we construct a hierarchy of best practices for the selection of body mass estimation equations in Equus. As a case study, we explore body size variation in Pleistocene European Equus paleopopulations in relation to diet and vegetation structure in their paleoenvironments. We show a relationship between diet and body size in Equus: very large-sized species tend to have more browse-dominated diets than small and medium-sized species, and paleovegetation proxies indicate on average more open and grass-rich paleoenvironments for small-sized, grazing species of Equus. When more than one species of Equus co-occur sympatrically, the larger species tend to be less abundant and have more browse-dominated diets than the smaller species. We suggest that body size variation in Pleistocene Equus was driven by a combined effect of resource quality and availability, partitioning of habitats and resources between species, and the effect of environmental openness and group size on the body size of individuals.Peer reviewe
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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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