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1.
2.
The anatomy of a new articulated enantiornithine bird skeleton from the Late Cretaceous of Patagonia clearly indicates a capacity for powered flight, approaching that of modern birds. Enantiornithines possess some of the synapomorphies of the Ornithurae, although they retain plesiomorphic states for many other characters, mainly in the hind limb. Such a mosaic character combination suggests a sister-group relationship between Enantiornithes and Ornithurae. Derived features of the pectoral girdle are here considered as diagnostic for a major avian clade, the Ornithopectae, comprising all known birds other than Archaeopteryx. The combination of derived and primitive traits in the fore and hind limbs and their girdles in early ornithopectines reflects mosaic evolution, with flight-related modifications of the fore limb and pectoral girdle preceding those in the hind limb and pelvic girdle.  相似文献   

3.
Cione, A.L. & Gouiric-Cavalli, S., June 2012. Metaceratodus kaopen comb. nov. and M. wichmanni comb. nov., two Late Cretaceous South American species of an austral lungfish genus (Dipnoi). Alcheringa 36, 203–216. ISSN 0311-5518.

Metaceratodus wollastoni, an Australian species, was reported from Upper Cretaceous beds of Patagonia in 1997. Later, three new species (Ceratodus wichmanni, Ptychoceratodus kaopen and Ptychoceratodus cionei), based on scarce material, were described from the same region. Two of these species were later referred to Ferganoceratodus. After examining much more abundant and better-preserved material, we conclude that neither the occurrence of Metaceratodus wollastoni nor those of Ptychoceratodus and Ferganoceratodus in the Cretaceous of South America are supported. We consider that C. wichmanni and P. cionei are synonyms and we reassign the three putative species to Metaceratodus under two new combinations: M. kaopen comb. nov. and M. wichmanni comb. nov. Both differ from the other species of the genus in having pits over most of the occlusal surface and a different occlusal profile of the tooth plate, and most have four ridges in the lower and upper tooth plates. Metaceratodus wichmanni differs from M. kaopen in oclussal profile, inner angle, and symphysis development among other features. Metaceratodus kaopen is known from the upper Santonian–lower Campanian Anacleto Formation of Río Negro province and M. wichmanni from upper Campanian–lower Maastrichtian units of Chubut, Río Negro, Neuquén and Mendoza provinces, Argentina. The occurrence of Metaceratodus in southern South America corroborates a close biogeographical relationship with Australia in the latest Cretaceous.

Alberto Luis Cione [acione@museo.fcnym.unlp.edu.ar] and Soledad Gouiric-Cavalli [sgouiric@museo.fcnym.unlp.edu.ar], División Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque s/n, W1900FWA La Plata, Argentina. Received 23.11.2010, revised 11.7.2011, accepted 7.8.2011.

  相似文献   

4.
Poropat, S.F., Nair, J.P., Syme, C.E., Mannion, P.D., Upchurch, P., Hocknull, S.A., Cook, A.G., Tischler, T.R. &; Holland, T. XX.XXXX. 2017. Reappraisal of Austrosaurus mckillopi Longman, 1933 Longman, H.A., 1933. A new dinosaur from the Queensland Cretaceous. Memoirs of the Queensland Museum 10, 131144. [Google Scholar] from the Allaru Mudstone of Queensland, Australia’s first named Cretaceous sauropod dinosaur. Alcheringa 41, 543–580. ISSN 0311-5518

Austrosaurus mckillopi was the first Cretaceous sauropod reported from Australia, and the first Cretaceous dinosaur reported from Queensland (northeast Australia). This sauropod taxon was established on the basis of several fragmentary presacral vertebrae (QM F2316) derived from the uppermost Lower Cretaceous (upper Albian) Allaru Mudstone, at a locality situated 77 km west-northwest of Richmond, Queensland. Prior to its rediscovery in 2014, the type site was considered lost after failed attempts to relocate it in the 1970s. Excavations at the site in 2014 and 2015 led to the recovery of several partial dorsal ribs and fragments of presacral vertebrae, all of which clearly pertained to a single sauropod dinosaur. The discovery of new material of the type individual of Austrosaurus mckillopi, in tandem with a reassessment of the material collected in the 1930s, has facilitated the rearticulation of the specimen. The resultant vertebral series comprises six presacral vertebrae—the posteriormost cervical and five anteriormost dorsals—in association with five left dorsal ribs and one right one. The fragmentary nature of the type specimen has historically hindered assessments of the phylogenetic affinities of Austrosaurus, as has the fact that these evaluations were often based on a subset of the type material. The reappraisal of the type series of Austrosaurus presented herein, on the basis of both external morphology and internal morphology visualized through CT data, validates it as a diagnostic titanosauriform taxon, tentatively placed in Somphospondyli, and characterized by the possession of an accessory lateral pneumatic foramen on dorsal vertebra I (a feature that appears to be autapomorphic) and by the presence of a robust ventral mid-line ridge on the centra of dorsal vertebrae I and II. The interpretation of the anteriormost preserved vertebra in Austrosaurus as a posterior cervical has also prompted the re-evaluation of an isolated, partial, posterior cervical vertebra (QM F6142, the ‘Hughenden sauropod’) from the upper Albian Toolebuc Formation (which underlies the Allaru Mudstone). Although this vertebra preserves an apparent unique character of its own (a spinopostzygapophyseal lamina fossa), it is not able to be referred unequivocally to Austrosaurus and is retained as Titanosauriformes indet. Austrosaurus mckillopi is one of the oldest known sauropods from the Australian Cretaceous based on skeletal remains and potentially provides phylogenetic and/or palaeobiogeographic context for later taxa such as Wintonotitan wattsi, Diamantinasaurus matildae and Savannasaurus elliottorum.

Stephen F. Poropat* [; ] Department of Chemistry and Biotechnology, Swinburne University of Technology, John St, Hawthorn, Victoria 3122, Australia; Jay P. Nair [; ] School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Caitlin E. Syme [] School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Philip D. Mannion [] Department of Earth Science and Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK; Paul Upchurch [] Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK; Scott A. Hocknull [] Geosciences, Queensland Museum, 122 Gerler Rd, Hendra, Queensland 4011, Australia; Alex G. Cook [] School of Earth Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Travis R. Tischler [] Australian Age of Dinosaurs Museum of Natural History, Lot 1 Dinosaur Drive, PO Box 408, Winton, Queensland 4735, Australia; Timothy Holland [] Kronosaurus Korner, 91 Goldring St, Richmond, Queensland 4822, Australia. *Also affiliated with: Australian Age of Dinosaurs Museum of Natural History, Lot 1 Dinosaur Drive, PO Box 408, Winton, Queensland 4735, Australia.  相似文献   

5.
The first lungfish tooth plate from the Las Flores Formation, Chubut, southern Argentina, is described. This is the youngest ceratodontid known from the continent. In Africa, ceratodonts disappeared in the Eocene. Afterwards, they are only known from Australia until their extinction during the Pleistocene. The Las Flores tooth plate also represents the southernmost lungfish known since the Coniacian (early Late Cretaceous).  相似文献   

6.
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In South America, various state organizations have an investment in producing some kind of ‘national’ cinema. Although different countries around the world have varied levels of government involvement, the four countries I would like to examine – Argentina, Bolivia, Chile and Peru – can be drawn upon for their similarities and the shared regional context in which their policies operate. Particularly important is the fact that an increase in government involvement and support has been taking place in the twenty‐first century against predictions that enhanced global capital would weaken the function of the state. Furthermore, it is frequently the case that policy, in the form of government regulation and funding, provides the only means for cinema’s continued existence, visibility and access to the public and thus cannot be underestimated. Complicating these factors is the fact that while legislation is in place, government bodies often struggle to implement the policies in a practical manner. This article examines these issues and suggests the effect they are having on the cinematic culture of the region.  相似文献   

8.
The time of appearance of a persistent and demographically-viable hunter-gatherer population in late Pleistocene southern South America must be determined by evaluating evidence from as large as possible a sample of candidate archaeological sites in the region. We co-ordinated the AMS dating of multiple bone and charcoal samples from previously-excavated strata at the following sites: Arroyo Seco 2, Paso Otero 5, Piedra Museo, and Cueva Tres Tetas (all in Argentina), and Cueva del Lago Sofia 1 and Tres Arroyos (both in Chile). With one possible exception, we did not obtain new results to confirm earlier observations of pre-Clovis-age cultural activity at any of the sites considered in this study. The possible exception, Arroyo Seco 2, is considered in detail elsewhere [Politis G., Gutierrez M.A., Scabuzzo, C. (Eds), in press. Estado actual de las Investigaciones en el sitio 2 de Arroyo Seco (región pampeana, Argentina). Serie Monográfica INCUAPA 5. Olavarría]. However, our results for the samples which were the most preferred indicators of cultural events (hearth charcoal and cut-marked bone) confirm that people were in the southern cone of South America at or soon after 11,000 BP (13,000 cal BP). Considered alongside recent age estimates for the Clovis culture in North America, these results imply the contemporaneous emergence of a consistent and archaeologically-robust human occupation signal at widely-separated locations across the Western Hemisphere. Such findings suggest that Palaeoindian demic expansion may have involved more than one terminal Pleistocene dispersal episode.  相似文献   

9.
The multiple and varied trajectories of chiefdom development in northern South America (and adjacent Central America) offer a rich opportunity for evaluating generalizations about the processes of chiefdom development. Sequences of the south coast of Ecuador, the Alto Magdalena, Calima, the Muisca region, Barinas, and the Tairona region are well enough documented to attempt to use in this way. Although centralized hierarchical societies develop in all these regions, there are many differences in the character of centralization and hierarchy and in the pacing of the development, and none of the traditionally proposed forces of social change is entirely adequate to account for these cases. Attention to the role played by competition between aspiring chiefs and their factions offers promise for more satisfactory generalizations that could be evaluated through further comparative study.  相似文献   

10.
11.
Archaeology is a practice that exists within various social contexts. As such, the way it is practiced is dependent upon the class interests of those who fund and undertake archaeological investigations. These interests in turn can be influenced by existing political regimes. In this article, I discuss how class interests have influenced the direction of Brazilian archaeology for the past century and a half.  相似文献   

12.
    
Here we report the first example of associated short-faced bear fossils from South America. The specimens represent three individuals referable to the Ensenadan (early to middle Pleistocene) species Arctotherium angustidens (Ursidae, Tremarctinae), the giant South American short-faced bear. Although the fossil record of short-faced bears in South America is very rich, they have not previously been recorded in association. These three individuals were found in a cave during quarry exploitation. We suggest that these bears represent the first record of a family group and open the discussion about cave utilization and hibernation or torpor by South American short-faced bears.  相似文献   

13.
Orinoquia is one of the most important riverine ecosystems complexes of the world. However, it has been seldom recognized as an ecological or historical entity in general accounts of South American archaeology. This essay reviews systematically and comparatively the archaeology of Orinoquia, by discussing research done from the 1940s onwards in all the areas of the Orinoco Basin: the Andes, the plains or llanos, the Orinoco river proper, the highlands of Guayana, and the Delta. It is proposed that, in the last 20 years, there has been a sustained movement away from a traditional archaeology, concerned mostly with environmental determinism and cultural history, to new and pluralistic models that share, in spite of their diversity, a regional, long-term, and multidisciplinary approach.  相似文献   

14.
    
Lucy Riall 《Modern Italy》2014,19(1):41-52
In this article, it is argued that Garibaldi's global fame owes much to his own experiences as a migrant and exile in the Americas. Overseas, Garibaldi not only acquired several practical and political skills, he also built up an important network of friends and supporters and became a hybrid figure able to adapt his image to diverse political settings. At the same time, Garibaldi relied on the trope of exile, developed by people like Ugo Foscolo, to define his opposition to, first, Italy's Restoration governments and, after Italian unification, the new moderate liberal regime. The article also looks at Garibaldi's life on Caprera and it is further argued that here Garibaldi combined elements of his previous experiences to fashion a role for himself as a ‘foreigner in Italy’. Garibaldi was a symbol of many worlds as well as a hero of two and it is precisely this hybrid nature of his appeal that can explain his global popularity.  相似文献   

15.
    
Prosopiscus is particularly important in Ordovician palaeobiogeography because of its wide geographic distribution in Gondwana and peri-Gondwanan regions. It appears to have been confined to low palaeolatitudes, representing a characteristic member of the warm water eastern Gondwanan shelf faunas. Trends in the distribution of the Ordovician genus can be observed due to its long stratigraphic range. Prosopiscus was restricted to, and may have originated in, Australia during the late Early Ordovician (Bendigonian-Chewtonian). By the Middle Ordovician (Darriwilian), Prosopiscus had dispersed to other parts of Gondwana and peri-Gondwana, including the North and South China blocks, Tarim, central Himalayas, and the Argentine Precordillera (South America). Possible explanations for the distribution of Prosopiscus are that: (1) there were no oceanic barriers preventing dispersal of trilobites between different regions of Gondwana, thus permitting uninhibited migration over vast distances; (2) Prosopiscus was not restricted to a specific biofacies; (3) a major eustatic transgression during the early Darriwilian may have facilitated the dispersal of Prosopiscus in allowing further development and expansion of marine environments; and (4) a prolonged planktonic larval stage may have permitted wide dispersal.

Prosopiscus lauriei sp. nov. is described from the late Early Ordovician (Bendigonian-Chewtonian) Tabita Formation at Mount Arrowsmith, northwestern New South Wales, Australia. The new species is closely related to P. praecox, from the Nora Formation, Georgina Basin, central Australia, and to P. magicus from northwest China.  相似文献   

16.
    
Azurduya gen. nov. (Brachiopoda: Camarotoechiidae) is described from Early Carboniferous sequences in the Argentine Precordillera and northern Chile. Marine assemblages and the palynoflora associated with this genus suggest a Tournaisian age. The type species Azurduya chavelensis (Amos, 1958) is reviewed and redescribed from material from the type locality. Additional material from equivalent localities in the Rio Blanco Basin (La Rioja and San Juan provinces, Argentine Precordilera) has been used to understand ontogenetic changes as well intraspecific variation. Azurduya cingolanii sp. nov. is proposed.  相似文献   

17.
Diederle, J.M., 1.8.2015. Systematic status of the Miocene darter ‘Liptornishesternus Ameghino, 1895 (Aves, Suliformes, Anhingidae) from Patagonia, Argentina. Alcheringa 39, 589–594. ISSN 0311-5518.

Liptornis hesternus was established by Ameghino in the late 1800s on the basis of a cervical vertebra (NHMUK-A599) from the Santa Cruz Formation (Santacrucian, South American Land Mammal Age, early Miocene, Burdigalian Stage) of Patagonia, Argentina. Although taxonomic attributions were controversial, the specimen is now confidently assigned to Anhingidae. Recently, however, L. hesternus was designated a nomen dubium because of its uninformative diagnostic characters and apparent loss of the holotype. Nevertheless, NHMUK-A599 has been relocated and is redescribed here prompting referral to Anhinga. A combination of traits are shared with the extant Anhinga anhinga and A. melanogaster, and the material is dimensionally compatible with A. anhinga. The estimated body size of NHMUK-A599 would have been larger than A. minuta but less than A. grandis, A. subvolans, A. fraileyi and A. walterbolesi. Finally, Anhinga hesterna is considered valid and represents the stratigraphically oldest occurrence of the genus in South America and the southernmost yet recorded.

Juan M. Diederle [], Laboratorio de Paleontología de Vertebrados, Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción (CICYTTP-CONICET), Materi y España, E3105BWA Diamante, Entre Ríos, Argentina.  相似文献   

18.
Abstract

Italian historians have not yet seriously confronted the emigration of 27 million Italians as an interpretative theme. Part II of this two‐part article studies Italian migrants’ experiences in France, South America, Switzerland and Germany, comparing ‘Latin’ and ‘Germanic’ receiving areas to the English‐speaking world discussed in Part I. A focus on these other sections of the Italian diaspora challenges some fundamental interpretations of historians of Italy about emigration: Italian migrations to these areas were neither limited to the late nineteenth century, sparked by the economic crises of those yean, nor a product of the ‘problem of the Mezzogiomo’. Italian historians have special opportunities to study return migration to Italy, and to interpret Italy's own evolution into a multicultural receiving country, by comparing it to the models of multi‐ethnic nations where Italian migrants once settled around the world.  相似文献   

19.
Acosta Hospitaleche, C. & Olivero, E., April 2016. Re-evaluation of the fossil penguin Palaeeudyptes gunnari from the Eocene Leticia Formation, Argentina: additional material, systematics and palaeobiology. Alcheringa 40, xx–xx. ISSN 0311-5518

Eocene penguins are known mostly from Antarctic specimens. A previously documented partial skeleton consisting of a pelvis, femur, tibiotarsus and fibula, from the middle Eocene Leticia Formation, Tierra del Fuego Province, Argentina, has been prepared and re-described. Re-analysis favours assignment to Palaeeudyptes gunnari, a species widely recorded in the Eocene of Antarctica. A new isolated coracoid belonging to an indeterminate species reveals new information about diving kinematics and swimming abilities. Palaeobiological attributes and morphology of the fossils indicate that both specimens belonged to large penguins with poor diving capability and wing propulsion systems similar to those of extant taxa. These penguin remains are the only vertebrate fossils thus far recorded from the Leticia Formation, and provide important insights into the relationships of South American and Antarctic penguins during the Paleogene. The presence of Palaeeudyptes in Argentina supports an Eocene connection between the South American and Antarctic penguin faunas.

Carolina Acosta Hospitaleche [], CONICET. División Paleontología Vertebrados, Museo de La Plata Paseo del Bosque s/n, 1900 La Plata, Facultad de Ciencias Naturales y Museo, UNLP, Argentina; Eduardo Olivero [], CONICET. Centro Austral de Investigaciones Científicas (CADIC-CONICET), B. Houssay 200, 9410 Ushuaia, Tierra del Fuego, Argentina.  相似文献   


20.
Gordillo, S., 2013. Muricid boreholes in Pleistocene acorn barnacles from the Beagle Channel: trophic interactions during the Last Interglacial in southern South America. Alcheringa 37, 1–8. ISSN 0311-5518.

Acorn barnacles with boreholes were recovered from a Pleistocene marine deposit on Navarino Island, on the southern coast of the Beagle Channel. Balanomorph shells were identified as Balanus laevis (Bruguière, 1789 Bruguière, J.G., 1789. Encyclopédie méthodique. Histoire naturelle des vers 1, 158–173, pis. Paris, 164–166. [Google Scholar]), and a few bear small round holes located generally on the middle or apical part of the parietal plates, thus suggesting that they represent the work of small muricid predators. If so, this study is the first record of drilling predation on fossil barnacles reported in southern South America.

[Sandra Gordillo [sgordillo@cicterra-conicet.gov.ar], Centro de Investigaciones en Ciencias de la Tierra, Consejo Nacional de Investigaciones Científicas y Técnicas (CICTERRA, CONICET-UNC); Centro de Investigaciones Paleobiológicas (CIPAL), Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba. Av. Vélez Sársfield 1611 X5016GCA Córdoba, Argentina. Received 8.1.2013; revised 26.3.2013; accepted 2.4.2013  相似文献   

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