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    Wyświetlanie 1-14 z 14
    Tytuł:
    Isolated theropod teeth from the Cretaceous strata of Khouribga, Morocco
    Autorzy:
    Niedźwiedzki, G.
    Gierliński, G.
    Powiązania:
    https://bibliotekanauki.pl/articles/2059918.pdf
    Data publikacji:
    2002
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Morocco
    Cretaceous
    theropoda
    dinosauria
    Carcharodontosauridae
    Spinosauridae
    Opis:
    Predatory dinosaur (Theropoda) teeth are described from Khouribga near Casablanca (Ad-Dar al-Bajda) in northern Morocco. A morphological study of specimens shows that two teeth represent the family Spinosauridae. A third tooth shows features characteristic of the genus Carcharodontosaurus. These are the first finds of dinosaurs from Khouribga.
    Źródło:
    Geological Quarterly; 2002, 46, 1; 97-100
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A new approach to evaluate the cursorial ability of the giant theropod Giganotosaurus carolinii
    Autorzy:
    Blanco, R E
    Mazzetta, G V
    Powiązania:
    https://bibliotekanauki.pl/articles/21508.pdf
    Data publikacji:
    2001
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    Cretaceous
    Theropoda
    Dinosauria
    theropod
    dinosaur
    Giganotosaurus
    South America
    Giganotosaurus carolinii
    Opis:
    The cursorial capability of the South American giant theropod Giganotosaurus carolinii should have been quite limited taking into account the strength indicator of its femur (approximately 7 GPa⁻¹) as well as the risk of experiencing grave or even lethal injuries involved in the falling of this multitonne animal on a run. However, even at low speeds a fall would have caused serious injuries. Thus, in accordance to the approach developed in this study, the maximum speed of Giganotosaurus should be not that which will implicate corporal lesions with minimum probability of lethalness. Instead, its maximum speed should be that which would permit the recovery of body equilibrium as each step is taken. Taking into consideration this approach, an indicator of stability is defined for bipedal, cursorial animals. This indicator is determined by the relationship between the time available for the movement of hip joint during the retraction of a hindlimb and the time needed to move the opposite hindlimb by an angle (in function of the speed) of sufficient magnitude as to facilitate the recovery of body equilibrium. This indicator was used to estimate the maximum speed of locomotion of Giganotosaurus (about 14 m s⁻¹) at which, from a kinematic point of view, the danger of falling does not exist.
    Źródło:
    Acta Palaeontologica Polonica; 2001, 46, 2
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Caudipteryx as a non-avalian theropod rather than a flightless bird
    Autorzy:
    Dyke, G J
    Norell, M.A.
    Powiązania:
    https://bibliotekanauki.pl/articles/22434.pdf
    Data publikacji:
    2005
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    bird
    Avialae
    feather
    Cretaceous
    Caudipteryx zoui
    China
    Theropoda
    Dinosauria
    Yixian Formation
    paleontology
    Opis:
    Caudipteryx zoui is a small enigmatic theropod known from the Early Cretaceous Yixian Formation of the People’s Republic of China. From the time of its initial description, this taxon has stimulated a great deal of ongoing debate regarding the phylogenetic relationship between non−avialan theropods and birds (Avialae) because it preserves structures that have been uncontroversially accepted as feathers (albeit aerodynamically unsuitable for flight). However, it has also been proposed that both the relative proportions of the hind limb bones (when compared with overall leg length), and the position of the center of mass in Caudipteryx are more similar to those seen in extant cusorial birds than they are to other non−avialan theropod dinosaurs. This conclusion has been used to imply that Caudipteryx may not have been correctly interpreted as a feathered non−avialan theropod, but instead that this taxon represents some kind of flightless bird. We review the evidence for this claim at the level of both the included fossil specimen data, and in terms of the validity of the results presented. There is no reason—phylogenetic, morphometric or otherwise—to conclude that Caudipteryx is anything other than a small non−avialan theropod dinosaur.
    Źródło:
    Acta Palaeontologica Polonica; 2005, 50, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Avialan status for Oviraptorosauria
    Autorzy:
    Maryanska, T
    Osmolska, H.
    Wolsan, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/23106.pdf
    Data publikacji:
    2002
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    bird
    Avialae
    phylogenetic analysis
    Cretaceous
    phylogenetic nomenclature
    Theropoda
    Dinosauria
    dinosaur
    Oviraptorosauria
    paleontology
    Opis:
    Oviraptorosauria is a clade of Cretaceous theropod dinosaurs of uncertain affinities within Maniraptoriformes. All previous phylogenetic analyses placed oviraptorosaurs outside a close relationship to birds (Avialae), recognizing Dromaeosauridae or Troodontidae, or a clade containing these two taxa (Deinonychosauria), as sister taxon to birds. Here we present the results of a phylogenetic analysis using 195 characters scored for four outgroup and 13 maniraptoriform (ingroup) terminal taxa, including new data on oviraptorids. This analysis places Oviraptorosauria within Avialae, in a sister−group relationship with Confuciusornis. Archaeopteryx, Therizinosauria, Dromaeosauridae, and Ornithomimosauria are successively more distant outgroups to the Confuciusornis−oviraptorosaur clade. Avimimus and Caudipteryx are successively more closely related to Oviraptoroidea, which contains the sister taxa Caenagnathidae and Oviraptoridae. Within Oviraptoridae, “Oviraptor” mongoliensis and Oviraptor philoceratops are successively more closely related to the Conchoraptor−Ingenia clade. Oviraptorosaurs are hypothesized to be secondarily flightless. Emended phylogenetic definitions are provided for Oviraptoridae, Caenagnathidae, Oviraptoroidea, Oviraptorosauria, Avialae, Eumaniraptora, Maniraptora, and Maniraptoriformes.
    Źródło:
    Acta Palaeontologica Polonica; 2002, 47, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An articulated pes from a small parvicursorine alvarezsauroid dinosaur from Inner Mongolia, China
    Autorzy:
    Hone, D.W.E.
    Choiniere, J.N.
    Tan, Q.
    Xu, X.
    Powiązania:
    https://bibliotekanauki.pl/articles/21549.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    paleontology
    Dinosauria
    Theropoda
    maniraptoran
    arctometatarsalian organism
    Cretaceous
    Inner Mongolia
    alvarezsauroid dinosaur
    dinosaur
    China
    Opis:
    A near complete and articulated parvicursorine pes from the Campanian Wulansuhai Formation is described. This pes is referred to the genus Linhenykus and is one of the first foot skeletons to be described for a derived alvarezsaur, providing new information on the first digit of the pes. The evolution of a laterally directed flange of the anterior face of the distal third metatarsal in arctometatarsalian taxa is described and discussed. This flange may have increased stability of the foot during cursorial locomotion and may also provide useful taxonomic and systematic data.
    Źródło:
    Acta Palaeontologica Polonica; 2013, 58, 3
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A new ornithomimid dinosaur with gregarious habits from the Late Cretaceous of China
    Autorzy:
    Kobayashi, Y
    Lu, J.C.
    Powiązania:
    https://bibliotekanauki.pl/articles/20983.pdf
    Data publikacji:
    2003
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    Cretaceous
    Late Cretaceous
    Theropoda
    Dinosauria
    China
    Ornithomimosauria
    gragarious habit
    dinosaur
    Ornithomimidae
    paleontology
    ornithomimid dinosaur
    Opis:
    At least fourteen ornithomimid skeletons were recovered from the Upper Cretaceous Ulansuhai Formation in Nei Mongol (Inner Mongolia) Autonomous Region of China. They are assigned to a new genus and species, Sinornithomimus dongi. The anatomy of the species is described. Comparative and phylogenetic studies of ornithomimosaurs prove that these skeletons represent a new taxon that is more derived than Archaeornithomimus and more basal than the clade of [(Anserimimus + Gallimimus)+[Struthiomimus + (Dromiceiomimus + Ornithomimus)]]. The phylogenetic analysis suggests that the structure of the hand is similar to Archaeornithomimus and represents an intermediate condition between the primitive (Harpymimus) and the derived (Anserimimus, Gallimimus, Struthiomimus, Dromiceiomimus, and Ornithomimus) conditions. The monophyly of Ornithomimidae is supported by a single synapomorphy (arctometatarsalian condition) in this analysis, indicating that the family is not as strongly supported as previously suggested. The analysis also implies that the shape of the rhamphotheca in North American taxa may have been different from that in Asian taxa. Previous study suggests herbivorous habits of this dinosaur based on characteristics of the gastroliths. The skeletons of Sinornithomimus were collected from a single monospecific bonebed with a high ratio of juvenile individuals (11 of the 14), suggesting gregarious behavior for protection from predators. The abundance of juveniles indicates high mortality of juveniles or a catastrophic mass mortality of a population with a high proportion of juveniles. An increase in the relative ratio of the tibia to femur through the ontogeny of Sinornithomimus suggests higher cursoriality in adult individuals than in juveniles.
    Źródło:
    Acta Palaeontologica Polonica; 2003, 48, 2
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Large theropod dinosaur footprint associations in western Gondwana: Behavioural and palaeogeographic implications
    Autorzy:
    Moreno, K.
    de Valais, S.
    Blanco, N.
    Tomlinson, A.J.
    Jacay, J.
    Calvo, J.O.
    Powiązania:
    https://bibliotekanauki.pl/articles/22773.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    large theropod dinosaur
    theropod dinosaur
    footprint
    Gondwana
    Theropoda
    behaviour
    paleogeography
    Early Cretaceous
    Cretaceous
    Chile
    Peru
    Opis:
    In modern terrestrial ecosystems, the population size of large predators is low, and a similar pattern has usually been assumed for dinosaurs. However, fossil finds of monospecific, large theropod accumulations suggest that population dynamics were more complex. Here, we report two Early Cretaceous tracksites dominated by large theropod footprints, in Querulpa Chico (Peru) and Chacarilla (Chile). The two sites correspond to distinct depositional environments—tidal basin/delta (Querulpa Chico) and meandering river (Chacarilla)—with both subject to extensive arid or semiarid palaeoclimatic conditions. Although most trackways show no preferred orientation, a clear relationship between two trackmakers is observed in one instance. This observation, coupled with the high abundance of trackways belonging to distinct large theropods, and the exclusion of tracks of other animals, suggests some degree of grouping behaviour. The presence of freshwater sources in a dry climate and perhaps social behaviour such as pair bonding may have promoted interactions between large carnivores. Further, the occurrence of these two tracksites confirms that large theropod dinosaurs, possibly spinosaurids and/or carcharodontosaurids, existed on the western margin of Gondwana as early as the earliest Cretaceous.
    Źródło:
    Acta Palaeontologica Polonica; 2012, 57, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada
    Autorzy:
    Currie, P J
    Powiązania:
    https://bibliotekanauki.pl/articles/20676.pdf
    Data publikacji:
    2003
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    Late Cretaceous
    Cretaceous
    Canada
    Theropoda
    dinosaur
    Alberta
    Saurischia
    Coelurosauria
    anatomy
    Dinosauria
    Tyrannosauridae
    skull
    paleontology
    tyrannosaurid dinosaur
    Opis:
    Beautifully preserved, nearly complete theropod skeletons from Alberta (Canada) allow re−evaluation of the taxonomic status of North American tyrannosaurids. It is concluded that the most parsimonious interpretation of relationships leads to the separation of the two species of Albertosaurus(sensu Russell 1970) into Gorgosaurus libratusfrom the Campanian Dinosaur Park Formation and Albertosaurus sarcophagus from the upper Campanian/lower Maastrichtian Horseshoe Canyon Formation. Albertosaurus and Gorgosaurus are closely related, but can be distinguished from each other by more characters than are known to justify generic distinction within another tyrannosaurid clade that includes Daspletosaurus, Tarbosaurus and Tyrannosaurus. Daspletosaurus is known from multiple species that cover extensive geographic, ecological and temporal ranges, and it is sensible to maintain its generic distinction from Tyrannosaurus. All tyrannosaurid species have consistent ontogenetic trends. However, one needs to be cautious in assessing ontogenetic stage because many characters are size−dependent rather than age−dependent. There are relatively few osteological differences that can distinguish tyrannosaurid species at any age. For example, Nanotyrannus lancensis is probably a distinct species from Tyrannosaurus rex because there is no evidence of ontogenetic reduction of tooth counts in any other tyrannosaurid species. Some characters that are good for separating mature tyrannosaurids, such as differences in the sizes and shapes of maxillary fenestrae, are not useful for identifying the species of juveniles.
    Źródło:
    Acta Palaeontologica Polonica; 2003, 48, 2
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A reassessment of Kelmayisaurus petrolicus, a large theropod dinosaur from the Early Cretaceous of China
    Autorzy:
    Brusatte, S.L.
    Benson, R.B.J.
    Xu, X.
    Powiązania:
    https://bibliotekanauki.pl/articles/21593.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    paleontology
    Kelmayisaurus petrolicus
    large theropod dinosaur
    theropod dinosaur
    Early Cretaceous
    China
    Dinosauria
    Theropoda
    Carcharodontosauridae
    anatomy
    Cretaceous
    Opis:
    The Early Cretaceous fossil record of large−bodied theropods from Asia is poor, hindering comparison of Asian predatory dinosaur faunas with those from other continents. One of the few large Asian theropod specimens from this interval is a partial skull (maxilla and dentary) from the Lianmugin Formation (?Valanginian–Albian), the holotype of Kelmayisaurus petrolicus. Most authors have either considered this specimen as an indeterminate basal tetanuran or a nomen dubium. We redescribe K. petrolicus and note that it possesses a single autapomorphy (a deep accessory groove on the lateral surface of the anterior dentary), as well as a unique combination of characters that differentiates it from other theropods, affirming its validity. A phylogenetic analysis recovers K. petrolicus as a basal carcharodontosaurid, which is supported by various features: very deep interdental plates (a carcharodontosaurid synapomorphy), fused interdental plates (present in carchardontosaurids and a limited number of other theropods), and the absence of diagnostic features of other clades of large−bodied theropods such as abelisaurids, megalosauroids, and coelurosaurs. As such,Kelmayisaurusis the second known carcharodontosaurid from Asia, and further evidence that this clade represented a global radiation of large−bodied predators during the Early–mid Cretaceous.
    Źródło:
    Acta Palaeontologica Polonica; 2012, 57, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Filling the ceratosaur gap: A new ceratosaurian theropod from the Early Cretaceous of Spain
    Autorzy:
    Sanchez-Hernandez, B.
    Benton, M.J.
    Powiązania:
    https://bibliotekanauki.pl/articles/945890.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    filling
    ceratosaur gap
    new theropod
    theropod
    ceratosaurian theropod
    paleontology
    Dinosauria
    Theropoda
    Ceratosauria
    Barremian
    Early Cretaceous
    Cretaceous
    Spain
    Opis:
    Ceratosaurian theropods evolved in two bursts, first in the Middle and Late Jurassic and then in the Late Cretaceous, leaving a 20 Myr gap in the Early Cretaceous during which remains are rare. We describe here a new ceratosaurian theropod, Camarillasaurus cirugedae, from fluvial deposits of the Camarillas Formation (lower Barremian, Lower Cretaceous) of Camarillas, Teruel Province, NE Spain. The new theropod is represented by a collection of associated bones, including a tooth, a possible cervical vertebra, two sternal plates, the proximal part of a right tibia, a broken right scapulocoracoid, the incomplete sacrum, five caudal vertebrae, an isolated caudal neural arch, a chevron, an almost complete presacral rib and some fragments of vertebrae, ribs, and other elements. Camarillasaurus is differentiated from other theropods by the extreme depth of the tibia proximal end, and a deep longitudinal groove on the tibia. The new dinosaur is a ceratosaur, phylogenetically close to the base of the clade, and perhaps more derived than the Chinese basal ceratosaur Limusaurus. The new taxon is significant in the evolution of the ceratosaurian dinosaurs, being placed temporally between its more common Jurassic and mid-Upper Cretaceous relatives, and it is one of only a few from Laurasia.
    Źródło:
    Acta Palaeontologica Polonica; 2014, 59, 3; 581-600
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A new troodontid theropod from the Late Cretaceous of central China, and the radiation of Asian troodontids
    Autorzy:
    Lu, J
    Xu, L.
    Liu, Y.
    Zhang, X.
    Jia, S.
    Ji, Q.
    Powiązania:
    https://bibliotekanauki.pl/articles/20912.pdf
    Data publikacji:
    2010
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    new theropod
    Late Cretaceous
    Central China
    Asian troodontid
    troodontid
    Theropoda
    Troodontidae
    Xixiasaurus
    Cretaceous
    Henan province
    China
    paleontology
    Opis:
    A new troodontid dinosaur, Xixiasaurus henanensis gen. et sp. nov., from the Upper Cretaceous Majiacun Formation of the Xixia Basin, Henan Province, is erected, based on a partial skull. It is characterized by bearing 22 maxillary teeth, a distinct opening on the lateral surface of the base of nasal process of the premaxilla, the rostral end of the upper jaw forming a tapered U−shape, and the mandibular symphyseal region slightly inflected medially. Xixiasaurus is most closely related to the Mongolian Byronosaurus among troodontids. Byronosaurus, Urbacodon, and Xixiasaurus may form a new clade, suggesting an endemic radiation of troodontids across Asia, including multiple taxa without dental serrations. The discovery of Xixiasaurus in the Xixia Basin may imply that the Xixiasaurus−bearing Majiacun Formation is Campanian in age.
    Źródło:
    Acta Palaeontologica Polonica; 2010, 55, 3; 381-388
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Basal abelisaurid and carcharodontosaurid theropods from the Lower Cretaceous Elrhaz Formation of Niger
    Autorzy:
    Sereno, P C
    Brusatte, S.L.
    Powiązania:
    https://bibliotekanauki.pl/articles/21335.pdf
    Data publikacji:
    2008
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    Allosauroidea
    Cretaceous
    Elrhaz Formation
    paleontology
    Eocarcharia
    Africa
    Lower Cretaceous
    Theropoda
    Kryptops
    carcharodontosaurid theropod
    Abelisauridae
    theropod
    Carcharodontosauridae
    abelisaurid theropod
    Niger
    Opis:
    We report the discovery of basal abelisaurid and carcharodontosaurid theropods from the mid Cretaceous (Aptian–Albian, ca. 112 Ma) Elrhaz Formation of the Niger Republic. The abelisaurid, Kryptops palaios gen. et sp. nov., is represented by a single individual preserving the maxilla, pelvic girdle, vertebrae and ribs. Several features, including a maxilla textured externally by impressed vascular grooves and a narrow antorbital fossa, clearly place Kryptops palaios within Abelisauridae as its oldest known member. The carcharodontosaurid, Eocarcharia dinops gen. et sp. nov., is represented by several cranial bones and isolated teeth. Phylogenetic analysis places it as a basal carcharodontosaurid, similar to Acrocanthosaurus and less derived than Carcharodontosaurus and Giganotosaurus. The discovery of these taxa suggests that large body size and many of the derived cranial features of abelisaurids and carcharodontosaurids had already evolved by the mid Cretaceous. The presence of a close relative of the North American genus Acrocanthosaurus on Africa suggests that carcharodontosaurids had already achieved a trans−Tethyan distribution by the mid Cretaceous.
    Źródło:
    Acta Palaeontologica Polonica; 2008, 53, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The teeth of the unenlagiine theropod Buitreraptor from the Cretaceous of Patagonia, Argentina, and the unusual dentition of the Gondwanan dromaeosaurids
    Autorzy:
    Gianechini, F.A.
    Makovicky, P.J.
    Apesteguia, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/20408.pdf
    Data publikacji:
    2011
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    tooth
    unenlagiine theropod
    theropod
    Buitreraptor
    Cretaceous
    Patagonia
    Argentina
    dentition
    Gondwanan dromaeosaurid
    dromaeosaurid
    Theropoda
    Dromaeosauridae
    Unenlagiinae
    Dinosauria
    paleontology
    dinisaur tooth
    Opis:
    The Unenlagiinae is a clade of Gondwanan dromaeosaurid theropods mainly known from incomplete skeletal material. The group includes two recently discovered theropods, Buitreraptor and Austroraptor, from which cranial remains are available with in situ maxillary and dentary teeth, thus allowing the study of tooth morphology. Among the derived traits that diagnose the dentition of unenlagiines are: (i) high tooth count, (ii) small size of individual teeth when compared with skull height, (iii) absence of denticles and carinae, and (iv) presence of longitudinal grooves on the tooth crown. This suite of dental characteristics, shared between Buitreraptor and Austroraptor, can be considered as diagnostic of the Unenlagiinae or, at least, a more exclusive clade within the group. The teeth of Buitreraptor exhibit a remarkable labiolingual compression, whereas Austroraptor possesses more conical teeth, probably respective autapomorphic features. On one hand, these dental morphologies differ from those observed in most Laurasian dromaeosaurids and, for instance, could be considered as further proof of the purported vicariant evolution of the lineage on the southern continents. On the other hand, the morphological similarities (e.g., absence of denticles) between the teeth of unenlagiines and other theropod lineages, including Mesozoic birds and ornithomimosaurs, can be considered as the result of parallel trends related to dental reduction.
    Źródło:
    Acta Palaeontologica Polonica; 2011, 56, 2
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Osteology of the Late Cretaceous alvarezsauroid Linhenykus monodactylus from China and comments on alvarezsauroid biogeography
    Autorzy:
    Xu, X.
    Upchurch, P.
    Ma, Q.
    Pittman, M.
    Choiniere, J.
    Sullivan, C.
    Hone, D.W.E.
    Tan, Q.
    Tan, L.
    Xiao, D.
    Han, F.
    Powiązania:
    https://bibliotekanauki.pl/articles/20629.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    osteology
    Cretaceous
    Late Cretaceous
    alvarezsauroid
    Linhenykus monodactylus
    China
    biogeography
    Dinosauria
    Theropoda
    Parvicursorinae
    Treefitte
    dispersal
    vicariance
    sympatry
    Wulansuhai Formation
    Inner Mongolia
    Opis:
    The alvarezsauroid theropod Linhenykus monodactylus from the Upper Cretaceous of Inner Mongolia, China is the first knownmonodactyl non−avian dinosaur, providing important information on the complex patterns of manual evolution seen in alvarezsauroids. Herewe provide a detailed description of the osteology of this taxon. Linhenykus shows a number of fea− tures that are transitional between parvicursorine and non−parvicursorine alvarezsauroids, but detailed comparisons also re− veal that some characters had a more complex distribution. We also use event−based tree−fitting to perform a quantitative analysis of alvarezsauroid biogeography incorporating several recently discovered taxa. The results suggest that there is no statistical support for previous biogeographic hypotheses that favour pure vicariance or pure dispersal scenarios as explana− tions for the distributions of alvarezsauroids across SouthAmerica, NorthAmerica andAsia. Instead, statistically significant biogeographic reconstructions suggest a dominant role for sympatric (or “within area”) events, combined with a mix of vicariance, dispersal and regional extinction. At present the alvarezsauroid data set is too small to completely resolve the biogeographic history of this group: future studies will need to create larger data sets that encompass additional clades.
    Źródło:
    Acta Palaeontologica Polonica; 2013, 58, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-14 z 14

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