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FAKE OR SIMPLY “BEAUTIFIED”? AN EXAMPLE FROM A NEW SPECIMEN OF TETHYSAURUS NOPCSAI BARDET ET AL. 2003
No full textAs the paleontology is better known and fossil trading, legal and illegal, widespread, the probability of coming up to problematic specimens increases. And more often, these fossils are not directly collected by specialists, for whom it is important to determine whether authentic or fake, but become a source of enrichment for inexperienced people who live especially in poor countries (Mateus et al., 2008). The market of fossils is oriented more towards private collectors than to professional paleontologists and such type of consumer privilege the general aspect of the specimens in respect to their scientific value. It is also well known that such type of material frequently includes various types of fake (Padian, 2000; Zhou et al., 2002; Mateus et al., 2008).
Recently, the refurbishing of a private collection rich in nearly thousand specimens seized by Carabinieri del Nucleo Tutela Patrimonio Culturale (Ancona, Marche, Italy) in the locality of Serrapetrona (Macerata, Marche, Italy) and currently owned by Soprintendenza per i Beni Archeologici delle Marche (Italy) has given the chance to analyzed amazing and rare specimens.
In particular, one specimen captured the attention because of its beauty and its peculiarity: it showed characters of aquatic adaptations and similarities with both mosasaurs and aigialosaurs. It has been classified as Tethysaurus nopcsai Bardet et al. 2003, a basal mosasauroid of which there are only three fragmentary specimen described in the literature and the holotype consists only of a nearly complete articulated skull. At least at first sight, the specimen consisted of an apparently complete skeleton, about 1.6 m in length, well exposed on a whitish slab of about 80x90 cm. In front of such a dramatically important specimen, the questions about its provenance and its real scientific nature were pressing and because of the completeness of such a rare taxon, some doubts rose up about its authenticity.
In order to clear the mind of all suspicions, the fossil was submitted to CT-scan and X-Ray examinations to proceed subsequently to a general cleaning for removing the paint coverage and so showing the artifacts. After the cleaning and preparation following the results of the radiographic exams, it was possible to establish that the specimen consists of a complete skull and mandible with most of the axial skeleton and some elements of the appendicular one preserved.
All the make-up work, that at first sight can be interpreted as a case of forgery, has been done only to “beautify” the specimen and to increase its value on the market of private collectors. It seems worth of note that, even if the “preparation” neither damaged the specimen nor brought to a loss of scientific value, surely rendered harder the study.
To complete the tale of this specimen odyssey, it’s important to notify that the Tethysaurus specimen of Serrapetrona is still under study and probably will dramatically improve our knowledge about this taxon (Paparella in prep.).
The word “beautified” wants to enhance the importance of the scientific value that it’s still possible to retrieve from a made-up specimen. The aim of this work is to make a distinction between real frauds, chimeras, hoaxes, “Frankensteins” (Dalton, 2000b; 2004; Padian, 2000; Rowe et al., 2001; Milner et al., 2001; Mateus et al., 2008) and fossils that have been “beautified” just to increase their ostensive and economic value and not to invalidate their potential scientific value
THE FORGOTTEN ICHTHYOSAUR: REVALUATION OF THE FIRST OPHTHALMOSAURID SPECIMEN FROM THE UPPER JURASSIC OF THE MARCHE APENNINES (CENTRAL ITALY)
No full textWith the exception of the Triassic material of Monte San Giorgio, which is quite abundant and well-preserved, the Italian fossil record about ichthyosaurs for the remainder of the Mesozoic is very poor, and usually consists of few disarticulated elements. Lower Cretaceous remains have been described from the Northern Apennines, south of Modena and Bologna; another rostrum belonging to Platypterygius sp. has been recently reported from the Lessini Mts., near Verona; and a few vertebrae are reported from the Triassic of Sicily.
In the summer of 1976, an ichthyosaur specimen was discovered in the locality of Camponocecchio, near Genga (Ancona, Marche, Italy) in an Upper Jurassic outcrop of the Marche Apennines. The specimen consists of a reasonably complete skeleton crushed on a slab, with a disarticulated skull, partially articulated vertebral column (from the atlas-axis to the tail bend, with few missing vertebrae), part of the pectoral girdles and some elements of the forelimbs.
During the Late Jurassic, the Umbria-Marche area was occupied by a pelagic domain consisting of numerous structural highs and lows, as a result of the fragmentation and drowning of the pre-rifting Early Jurassic carbonate platform. The Genga ichthyosaur comes from the Calcari ad aptici e Saccocoma Formation (sensu Galluzzo & Santantonio, 2002), and thanks to the combination of the occurrence/lack of some micro- and macrofossils with biostratigraphic meaning, it has been possible to date the ichthyosaur-bearing level to the late Kimmeridgian – earliest Tithonian.
The history of the Genga ichthyosaur has always been problematic, mainly because of the lack of attention that the authorities turn to paleontological findings: it took more than 20 years before the specimen could find a proper location, where it was finally prepared and where it is still exposed, in the Abbey of San Vittore di Genga.
Since its discovery, few studies have focused on the Genga ichthyosaur (e. g. Fastelli & Nicosia, 1980; De Marinis & Nicosia, 2000), but never addressing its taxonomy and paleogeographical importance. This is the first time that this Mesozoic marine reptile is described and compared with other Late Jurassic and Early Cretaceous ichthyosaurs by including it in the most recent phylogenetic analysis of ophthalmosaurids
EXCEPTIONAL SOFT-TISSUE PRESERVATION IN A NEW MARINE PYTHONOMORPH FROM THE UPPER CRETACEOUS (CAMPANIAN) OF SOUTHERN ITALY
No full textA new pythonomorph lizard gen. et sp. nov. with exceptional soft-tissues preservation was found in Upper Cretaceous marine sediments of the Apulia platform (Southern Italy). Phylogenetically related forms (‘dolichosaurs’, e. g. Pontosaurus and Adriosaurus) have been described from Upper Cretaceous deposits of the Middle East (Lebanon) and the Balkan Peninsula (Croatia, Slovenia). This is the first record of this group of marine lizards from southern Italy, and extends the known paleobiogeographic distribution of ‘dolichosaurs’ towards the center of the Tethys. This taxon also extends the known temporal range for these marine lizards both globally and from the Tethyan realm; the new taxon is Campanian in age, while related taxa are Cenomanian – Turonian. The new specimen consists of an almost complete, articulated skeleton, most of which is exposed in ventral view. Pachyostotic dorsal vertebrae and ribs suggest aquatic adaptations. The slender and elongated humerus and femur are indicative of a basal degree of aquatic adaptation. Presence of unfused epiphyses and unfused pelvic girdle elements may be indicative either of paedomorphosis in an adult form, or of a juvenile condition. The preservation of the bones is unusual, as the elements retain a ‘fresh brittle look’ despite being about 80 million years old. Spectroscopic analysis (EDX/SEM) of the specimen revealed that, the original composition of the bones is likely retained, and that there is very little calcification (high phosphorous content). Different types of squamation are also preserved: 1) deeply imbricated polygonal scales (close to the trunk and forelimbs); 2) large diamond-shaped scales (in the trunk and tail regions); and 3) broad ventral scales similar to those of Pontosaurus kornhuberi and some snakes (visible in lateral view along the ventral margin of the tail). This specimen also preserves portions of mineralized epaxial and hypaxial musculature along the trunk and tail. Due to its exceptional state of preservation this specimen provides new information about the anatomy of dolichosaurs
The first ophthalmosaurid ichthyosaur from the Upper Jurassic of the Umbrian–Marchean Apennines (Marche, Central Italy)
No full textThe first ophthalmosaurid ichthyosaur from the Upper Jurassic deposits of the Central–
Northern Apennines (Marche, Italy) is here described for the first time. The specimen is relatively
complete and is referred to Gengasaurus nicosiai gen. et sp. nov. based on a unique combination of
characters, including a peculiar condition of the preaxial accessory facet on the humerus. The faunal
association of the ichthyosaur-bearing level indicates a late Kimmeridgian – earliest Tithonian age,
and its finding contributes significantly to our knowledge of the diversity of Late Jurassic ichthyosaurs
from the Western Tethys. Two shark teeth assigned to the order Hexanchiformes were also recovered
in association with the ichthyosaur specimen, suggesting that scavenging of the carcass might have
occurred. Gengasaurus can be referred to Ophthalmosauridae based on the reduced extracondylar
area of the basioccipital, and the presence of a preaxial digit. It differs from Ophthalmosaurus spp.
in several respects, including the shape of the posterior basisphenoid, the shape of the supraoccipital,
the anteriorly deflected preaxial facet of the humerus, and a proximodistally shortened ulna. The new
taxon actually shares diagnostic characters with both members of the two main lineages recovered in
previous phylogenetic analyses,more nested within Ophthalmosauridae. The affinities of Gengasaurus
to genera from both the northern and southern hemispheres also suggest that connectivity between
pelagic habitats was high during the early Late Jurassic, allowing dispersal of some forms, followed
by local, endemic divergence
First occurrence of an ophthalmosaurid ichthyosaur in the Upper Jurassic of the Northern Apennines (Marche, Central Italy): stratigraphic setting
No full textAn ophthalmosaurid ichthyosaur was discovered in Upper Jurassic deposits of the Umbria-Marche sedimentary succession near Genga (Ancona, Marche, Italy). While other Mesozoic marine reptiles have been found at different stratigraphic intervals in Italy, this specimen represents the first ichthyosaur ever recorded from the Upper Jurassic of the Apennines. It consists of an almost complete skeleton preserved on a slab, with an articulated vertebral column, and disarticulated skull and pectoral girdle. This paper describes the stratigraphy of the ichthyosaur-bearing deposits.
The Umbria-Marche sedimentary succession is characterized by Meso-Cenozoic pelagites and hemipelagites overlying Lower Jurassic shallow-water carbonates (Calcare Massiccio Fm.). The rifting stage, which affected the Western Tethys in the Early Jurassic, produced a complex submarine architecture, resulting in a mosaic of variable facies and thickness differences in the syn- and post-rift succession. Extension linked with opening of the Liguria - Piedmont Ocean dismembered and drowned a huge carbonate platform (Calcare Massiccio paleoplatform), and converted it into a system with small horsts-and-grabens/semigrabens, where pelagic deposits capped the shallow-water carbonates. The original Early Jurassic paleobathymetric differences were levelled by Early Cretaceous times. The basin-fill deposits onlapped the (mostly pre-rift) Calcare Massiccio facies, exposed at the footwall of Jurassic faults in the form of paleoescarpments, and buried the structural highs while their margins were largely inactive. The area in which the ichthyosaur was found was characterized by numerous structural highs (Mt. Murano, Mt. Revellone, Mt. Scoccioni and Mt. Valmontagnola), onlapped by the Jurassic - Early Cretaceous basin-fill units. In the Middle Jurassic, a huge block (about 0,7 km longer axis) of Calcare Massiccio - characterizing the Il Sassone sector - collapsed from the western escarpment of the Mt. Scoccioni or from the Mt. Revellone high, due to tectonic/gravitative instability. The olistolith was embedded in the “Calcari e marne a Posidonia” Fm. (late Toarcian-?late Bajocian), and subsequently was onlapped by the “Calcari Diasprigni” (?late Bajocian-early Kimmeridgian) and “Calcari ad aptici e Saccocoma” (Kimmeridgian p.p.-early Tithonian) Fms. Additional stratigraphic evidence for tectonic instability across the study area is found in the Middle Jurassic with gravity flow deposits, slumps and breccias bearing Calcare Massiccio clasts.
The specimen was discovered in the Upper Jurassic deposits onlapping the Il Sassone mega-olistolith. It was embedded in green and reddish limestones and cherty-limestones referable to the “Calcari ad aptici e Saccocoma” Fm. The faunal assemblage includes belemnites (Duvalia spp.), aptychi (Laevaptychus sp., ?Laevilamellaptychus sp.), rhyncholites (Leptocheilus sp.), shark teeth (hexanchiforms), trace fossils (Thalassinoides sp., Chondrites sp.), radiolarians, calcisphaerulids and abundant Saccocoma tenella. These elements, coupled with the absence of S. vernioryi, Chitinoidella spp. and calpionellids, constrain the age of the ichthyosaur to the late Kimmeridgian - earliest Tithonian
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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