23 research outputs found
The last European varanid: demise and extinction of monitor lizards (Squamata, Varanidae) from Europe
Remains of a varanid lizard from the middle Pleistocene of the Tourkobounia 5 locality near Athens, Greece are described. The new material comprises cranial elements only (one maxilla, one dentary, and one tooth) and is attributed to Varanus, the genus to which all European Neogene varanid occurrences have been assigned. Previously, the youngest undisputed varanid from Europe had been recovered from upper Pliocene sediments. The new Greek fossils therefore constitute the youngest records of this clade from the continent. Despite being fragmentary, this new material enhances our understanding of the cranial anatomy of the last European monitor lizards and is clearly not referable to the extant Varanus griseus or Varanus niloticus, the only species that could be taken into consideration on a present-day geographic basis. However, these fossils could represent a survivor of the monitor lizards of Asian origin that inhabited Europe during the Neogene
A new species of Varanus (Anguimorpha: Varanidae) from the early Miocene of the Czech Republic, and its relationships and palaeoecology
Skeletal remains of a new early Miocene (Ottnangian, MN 4 mammal zone) monitor lizard, Varanus mokrensis sp. nov., are described from two karst fissures in the Mokrá-Western Quarry (1/2001 Turtle Joint; 2/2003 Reptile Joint), Czech Republic, providing the first documented example of a European varanid for which osteological data permit a well-supported assignment to the genus Varanus. The new species is morphologically similar to the Recent Indo-Asiatic varanids of the Varanus bengalensis group. It differs from all other Varanus species on the basis of a single autapomorphy and a combination of 11 characters. As a distinguishing feature of V. mokrensis, the parietal and squamosal processes of the postorbitofrontal form a narrowly acute angle. The teeth show distinct, smooth cutting edges along the mesial and distal margins of the apical portion of their crowns. This feature is not observed in most extant Asiatic Varanus species and may represent a plesiomorphic condition. The results of parsimony phylogenetic analyses, with and without character reweighting, reveal poor resolution within Varanus. A Bayesian analysis shows V. mokrensis to be closely related to extant representatives of the Indo-Asiatic Varanus clade, with close affinities to the V. bengalensis species group. The topology of the Bayesian tree supports the hypothesis that Miocene monitors from Mokrá are representatives of a lineage that is ancestral to the well-defined clade of extant African varanids, including the early Miocene V. rusingensis. In addition, our results support a Eurasian origin for the varanid clade. The extant African Varanus species probably originated in the late Oligocene. The radiation of African varanids probably occurred during the late Oligocene to early Miocene time interval. The occurrence of Varanus in the early Miocene of Mokrá-Western Quarry corresponds to the warm phase of the Miocene Climatic Optimum. Remains of a diverse aquatic and heliophobe amphibian fauna at the 2/2003 Reptile Joint site indicate more humid conditions than those at the 1/2001 Turtle Joint site
Eredit\ue0 kantiane (1804-2004). Questioni emergenti e problemi irrisolti.
Progettazione del volume, invito degli autori, e curatela editoriale di saggi in italiano, tedesco e in inglese con abstract in inglese; Presentazione del volume e degli autori con abstracts in italiano; Nota bibliografica finale; proprio contributo in lingua inglese, per la celebrazione del bicentenario della morte di Kant (1804)
What Makes Cultural Heredity Unique? On Action-Types, Intentionality and Cooperation in Imitation
Sociology, Culture and Energy: The Case of Wilhelm Ostwald’s ‘Sociological Energetics’ – A Translation and Exposition of a Classic Text
Sociology has largely ignored the contribution of the German Nobel-Prize-winning chemist Wilhelm Ostwald to the sociology of energy, mainly due to Max Weber’s (1909) dismissive reception of Ostwald’s ‘energetical thought’. This article reclaims Ostwald’s significance for contemporary sociology, through a translation and exposition of ‘Sociological Energetics’, first published in 1908 as the final chapter of a popular book on energy. Ostwald’s deliberations, which derive from his engagement in contemporary debates on thermodynamics and energetics, brought him into contact with classical sociologists, including Rudolf Goldscheid, Georg Simmel, Ferdinand Tönnies and Weber. Ostwald’s contribution to sociology lies in his focus on the cultural significance of energy relations and transformations. In their encounters with Ostwald and energetics, Simmel, Tönnies and Weber all reveal the potential importance of Ostwald’s work on energy relations in thinking productively about the relationship between technology and culture
Tachypteron franzeni n. gen., n. sp., earliest emballonurid bat from the Middle Eocene of Messel (Mammalia, Chiroptera)
A new genus and species of emballonurid microchiropteran,Tachypteron franzeni, is described from the early Middle Eocene (MP 11) of Grube Messel, near Darmstadt, Germany. The holotype is extraordinarily well-preserved. It is the first unequivocal representative of an extant clade among Messel bats and the oldest unequivocal record of Emballonuridae. The flight apparatus ofT. franzeni is highly specialized for a rapid and constant flight style. The proportions of the strikingly narrow wing, the outline of the flight membranes and external ear, the morphology of the postcranial skeleton, and the relative cochlea size ofT. franzeni and extantTaphozous species are almost identical, while the dentition ofT. franzeni is distinguished by more plesiomorphic features.Tachypteron and the fairly diverse Paleogene record of emballonurids from France, consisting mainly of isolated teeth, document the earliest radiation known from an extant bat family and suggest a rather intense pre-Middle Eocene diversification of emballonurids