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View pageFigure 1. Evolution of macroecological traits in Dinosauria. Large scale event in dinosaur evolution (a); the origin of dinosaurs (star), hyperthermals (volcano), the earliest fossil Avialae (bird), the earliest fossil angiosperm (flower), the Cretaceous/Palaeogene mass extinction (asteroid). Phylogeny of dinosaurs (b) redrawn from Sereno and adapted to the current consensus and upon which an ancestral state reconstruction of temperature niche (mean annual temperature) after Chiarenza et al. is plotted; Mesozoic palaeogeographies (c) for Triassic (T), Jurassic (J) and Cretaceous (K). Silhouette colours symbolize body mass for each of the taxa represented; information on dietary habits are plotted after Barrett and Zanno & Makovicky; numbers represent clades discussed through this study: 1, Ornithischia; 2, Thyreophora; 3, Ornithopoda; 4, Hadrosauroidea; 5, Marginocephalia; 6, Ceratopsia; 7, Saurischia; 8, Sauropodomorpha; 9, Sauropoda; 10, Theropoda; 11, Ceratosauria; 12, Tetanurae; 13, Coelurosauria; 14, Maniraptoriformes; 15, Maniraptora; 16, Deinonychosauria; 17, Avialae; 18, Ornithothoraces. Palaeogeographies modified from original plots via R package ‘mapast’ using plate models by Scotese.
Representative taxa from the Santonian Iharkút fauna from the Csehbánya Formation, Bakony Mountains, western Hungary. A Pannoniasaurus inexpectatus (Squamata, Mosasauroidea), dorsal vertebra (MTM uncatalogued) in dorsal view (photo by Réka Kalmár) B Foxemys trabanti (Pleurodira, Bothremydidae), skull (MTM V 2010.215.1.) in dorsal view (photo by Márton Rabi). C Bicuspidon aff. hatzegiensis (Squamata, Borioteiioidea), left dentary (MTM 2006.112.1.) in medial view (photo by László Makádi) D Basal tetanuran (Theropoda, Tetanurae), tooth (MTM V.01.54) in ?lingual view E Indeterminate abelisaurid (Theropoda, Abelisauridae), pedal ungual phalanx (MTM V 2008.43.1.) in lateral view F Pneumatoraptor fodori (Theropoda, Paraves), left scapulocoracoid (holotype, MTM V 2008.38.1.) in lateral view G Mochlodon vorosi (Ornithopoda, Rhabdodontidae), left dentary (holotype, MTM V 2010.105.1) in lateral view H Bakonydraco galaczi (Pterosauria, Azhdarchidae), mandible (holotype, MTM 2007.110.1) in dorsal view I Iharkutosuchus makadii (Eusuchia, Hylaeochampsidae), skull (holotype, MTM 2006.52.1) in dorsal view J Hungarosaurus tormai (Ankylosauria, Nodosauridae), right dentary (MTM 2007.25.2) in lateral view K Bauxitornis mindszentyae (Aves, Enantiornithes), left tarsometatarsus (holotype, MTM V 2009.38.1) in anterior view L Ajkaceratops kozmai (Ceratopsia), fused rostral and premaxillae (holotype, MTM V 2009.192.1) in lateral view. Scale bars: 2 cm in A, V, G, H, I, J; 1 cm in D, E, F, K, L; 1 mm in C.
Simplified cladogram of Dinosauria with the distribution of feathers according to the fossil record. Despite its more ancient origin, it was only in maniraptoriformes that modern-type feathers (pennaceous feathers) have arisen (Based in Xu & Guo, 2009; Clarke, 2013; Godefroit et al., 2013; Han et al., 2014; Koshchowitz et al., 2014).
silhouette de carnosauriens
A family tree, showing the phylogenetic position of Carnosauria genera.
Ареал карнозавров
A collage of four carnosaurs: Yangchuanosaurus (or possibly Sinraptor), Acrocanthosaurus, Concavenator, Allosaurus, Torvosaurus, Suchomimus
Phylogram and comparison of body size optimization across Allosauroidea. Constructed from the trees recovered by (A) EAC, the present analysis. Silhouettes are to scale according to measurements listed in Table 6.
Diagram made to illustrate the debate over the hands of theropod dinosaurs and their alleged descendants, the birds ( Aves ). In the last years, the difference between the hands of theropods and birds have been an important thing when it comes question the theory that birds evolved from dinosaurs, even though some scientists may could refute it. In the diagram, a Neotheropoda ( 1 ), basal tetanurae ( 2 ), a coelurosaurian ( 3 ), the bird (?)Archaeopteryx ( 4 ) and modern bird ( 5 ). In 1997, birdexpert Alan Feduccia at University of North Carolina discovered that birds develop hands with the digits II, III and IV ( see The Cincinnati Enquirer, 25 - 10 - 1997 ). This is in contrast with the hands of tetanurae, which seems to have the digits I, II and III. This make it almost impossible for dinosaurs and birds to be closely related, according to Feduccia. Since the discovery by Feduccia, scientific research have came up with a possible explanation to the mystery of the dinosaur - bird hand difference, called The frame shift hypothesis ( see http://scienceblogs.com/tetrapodzoology/2009/06/limusaurus_is_awesome.php ). This hypothesis is based on a discovery which shows that although bird embryos develop the fingers II, III and IV, the genes which is coding for the external appearance of the digits seems to be from the fingers I, II and III. Based on this, scientists belive this: when neotheropods evolved into tetanurae, the losed digit I ( not digit IV, as earlier suggested ). During this process, the genes which coded for how the digits should looks like ( the number of phalanges, for example ) became refurnished ( see the color spots in th upper section in the diagram to understan ). The discovery of Limusaurus has been said to support this theory ( see https://www.livescience.com/animals/090617-dinosaur-hands.html ). One thing is that may can be used to refute that Limusaurus should support the Frame shift hypothesis is that Limusaurus was a ceratosaurian, and is dated to be much younger than the oldest tetanurae's. Also, some tetanure´s may had 4 digits' like the Archaeornithomimus ( see number 4 in the diagram ) ( see also http://dml.cmnh.org/1998Oct/msg00443.html and the Allosaurus hand in the image here: http://upload.wikimedia.org/wikipedia/commons/6/69/Allosaurus-mounted.jpg ). If this is the digits I, II, III and IV. If so, it shows that tetanurae had the digits I, II and III, and not II, II and IV, like birds. For more in this debate, see text section to my picture Raptor-Archaeopteryx-bird hands differens.JPG at http://commons.wikimedia.org/wiki/File:Raptor-Archaeopteryx-bird_hands_differens.JPG.
Cladogram of amniotes. Based on File:Cladogram Amniota A.jpg
Cladogram of the former "Reptilia" (red)
A collage of four carnosaurs: Yangchuanosaurus (or possibly Sinraptor), Acrocanthosaurus, Concavenator, and Allosaurus
A collage of four carnosaurs: Yangchuanosaurus (or possibly Sinraptor), Acrocanthosaurus, Concavenator, and Allosaurus
A collage of four carnosaurs: Yangchuanosaurus (or possibly Sinraptor), Acrocanthosaurus, Concavenator, and Allosaurus
A collage of four carnosaurs: Yangchuanosaurus (or possibly Sinraptor), Acrocanthosaurus, Concavenator, and Allosaurus
A collage of four carnosaurs: Yangchuanosaurus (or possibly Sinraptor), Acrocanthosaurus, Concavenator, and Allosaurus