1,720,976 research outputs found
The Villafranchian perissodactyls of Italy: knowledge of the fossil record and future research perspectives
No full textThe Villafranchian fossil record of Perissodactyla is of a great interest because the appearance of the genus Equus and disappearance of the genus Tapirus mark important faunal turnovers. Here, we provide new data on Italian Villafranchian Tapiridae, Rhinocerotidae, and Equidae with updates from the last comprehensive review; most relevant are those of the Rhinocerotidae and Equidae. At present only two Villafranchian rhinoceros’ species are documented in Italy: Stephanorhinus jeanvireti and Stephanorhinus etruscus. The two species can be distinguished by several morphological features and by the dimensions of their bones. Stephanorhinus etruscus occurred throughout the Villafranchian; despite the numerous records, its remains are not enough to investigate morphometric trends. The Equidae include seven species including new occurrences of Hipparionine horses and of the genus Equus. The statistical analyses performed on the Equus species show two different evolutionary trends, namely the stenonine lineage “Equus livenzovensis - Equus stenonis” and the small-to-medium-sized lineage “Equus senenzensis - Equus stehlini”, suggesting a different evolution of these species. Moreover, the analyses show close relationships between the Italian Equus stenonis samples and three European Equus stenonis subspecies (E. stenonis vireti, E. stenonis guthi, and E. stenonis pueblensis). We begin to reconsider the validity of E. stenonis subspecies identification in order to provide new perspectives on the taxonomy of this species
A late occurring “Hipparion” from the middle Villafranchian of Montopoli, Italy (Early Pleistocene; MN16b; ca. 2.5 Ma)
Full text linkWe report here for the first time the occurrence in the Montopoli large mammal fossil assemblage of a small equid taxon identified as “Hipparion” sp., associated to the monodactyl large horse Equus cf. livenzovensis. This occurrence has been recognised on a specimen that the late De Giuli (1938-1988) identified as Hipparion sp. in unpublished notes available in the archives of the Vertebrate Palaeontology Laboratory of the Dipartimento di Scienze della Terra at the Università degli Studi di Firenze. Although fragmentary, the specimen documents the occurrence of “Hipparion” at the middle Villafranchian (early Pleistocene, ca. 2.5 Ma) site of Montopoli, one of the latest occurrences of an hipparionine horse in western Europe. The western Eurasian “Hipparion” evolutionary history is summarised herein
Early Miocene (Burdigalian) acorn barnacles (Cirripedia: Sessilia) from the Chilcatay Formation of southern Peru: palaeoenvironmental, palaeobiogeographical and evolutionary significance
No full text- We report on a recently described barnacle-rich facies from the East Pisco Basin.
- Barnacles are associated with an abundant, mollusc-rich hard-substrate biota (i.e., a barnamol).
- The Chilcatay barnacle facies depicts a very shallow, high-energy, nearshore assemblage.
- Two new species of austromegabalanines have been described from this Burdigalian assemblage.
- Austromegabalanines likely originated at low latitudes and in warm marginal-marine waters
The Montopoli site, a reference Local Fauna in the Pliocene and Pleistocene European Large Mammals Biochronology, first discovered by Giovanni Capellini (1833-1922)
Full text linkEquus stenonis (Equidae, mammalia) from the early pleistocene of pantalla (italy) and the dispersion of stenonine horses in europe
No full textStenonine horses roamed across Eurasia for a long-time interval between the Early Pleistocene and the early Middle Pleistocene. These forms probably derived from North American Equus simplicidens and recent research suggests that they can be at the basis of the radiation of the extant African zebras. Equus stenonis is the most widespread stenonine horse in the Early Pleistocene of Europe. Here we describe the Equus record from Pantalla (Italy) and we refer it to E. stenonis based on a combination of morphometric analyses of metapodials and tibia. In particular, our comparisons show remarkable similarities between the Pantalla horse and E. stenonis from Saint Vallier (France). The studied sample allows suggesting an age close to the beginning of the late Villafranchian (~2 Ma) for the Pantalla assemblage, thus representing one of the earliest records of E. stenonis in Italy. Furthermore, our analyses highlight a substantial morphometric homogeneity in European E. stenonis samples, supporting that they may represent intraspecific variation of a single long-lasting widespread species
The lower Pliocene elasmobranch assemblage from Arcille (Campagnatico, Grosseto Province): palaeoecological and palaeoenvironmental significance
Full text link- Tuscany hosts a conspicuous fossil record of elasmobranchs.
- New stratigraphically informed studies are need to be performed.
- A newly discovered elasmobranch assemblage is described from the lower Pliocene Campagnatico locality.
- This diverse assemblage allows for a reconstruction of an early Pliocene marginal-marine palaeoenvironment of Tuscany
Equus cf. Livenzovensis from montopoli, Italy (early pleistocene; mn16b; ca. 2.6 ma)
Full text linkWe report here the occurrence and metric characteristics of a large species of Equus from Montopoli (Tuscany, Italy) correlated with the middle Villafranchian, 2.6 Ma (early Pleistocene). This species co-occurs with a rare “Hipparion” sp. at Montopoli. We compare the Montopoli Equus cf. livenzovensis with a large suite of extant Equus including zebras, asses and a large suite of fossil Equus using bivariate and log10 ratio analyses of anterior and posterior 1 st phalanges III. Our comparisons show that Montopoli anterior and posterior 1 st phalanges III are larger than in living zebras and asses and comparable in size and proportions to the early Pleistocene large Chinese species Equus eisenmannae and late Pleistocene Rancho La Brean Equus occidentale. Equus livenzovensis was a larger species than Equus stenonis and Equus stehlini. Equus cf. livenzovensis is not represented as far as we know by skulls and dentitions in the Italian Villafranchian record
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
3° Convegno Nazionale per Giovani Ricercatori in Paleontologia - IVP Day 2020 – Abstract Booklet
No full text- …
