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Voir la ficheSketch-drawing of the vertebrate faunal assemblage of the Lisowice site (modified from Niedźwiedzki)10. (a) Large, theropod-like predatory archosaur (Smok wawelski); (b) large temnospondyl amphibian (Cyclotosaurus sp.); (c) small predatory dinosaurs (Neotheropoda indet.); (d) temnospondyl amphibian (Gerrothorax sp.); (e) small basal crocodylomorph (Crocodylomorpha indet.); (f) small diapsid (Choristodere-like animal); (g) hybodont sharks (Polyacrodus and Hybodus); (h) coelacanth fish; (i) dipnoan fish (Ptychoceratodus sp.); (j) actinopterygian fish; (k) gigantic dicynodont; (l) dinosauriforms or early dinosaurs (Dinosauriformes indet. or Dinosauria indet.); (m) small lepidosauromorphs (Sphenodontia indet.); (n) pterosaurs (Pterosauria indet.); (o) early mammaliaform (Hallautherium sp.).
Kura z napędem typu Diesel :)
Restoration of Early Jurassic environment preserved at the SGDS, with the theropod Dilophosaurus wetherilli in bird-like resting pose, demonstrating the manufacture of SGDS.18.T1 resting trace.
Dilophosaurus Author:User:ArthurWeasley
Reconstruction of Coelophysis rhodesiensis.
Photographer: User:Ballista Edited in Adobe PhotoShop: User:Firsfron Photographed object is in fact a cast of a real fossil. It's part of a hands-on exhibit of the NHM in London.
A photograph of Coelophysis bauri taken at the Denver Museum of Nature and Science in 2007.
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.
Acrocanthosaurus, North Carolina Museum of Natural Sciences.
Six ceratosaurians (top to bottom): Rugops, Elaphrosaurus, Majungasaurus, Carnotaurus, Ceratosaurus, Berthasaura
Six ceratosaurians (top to bottom): Rugops, Elaphrosaurus, Majungasaurus, Carnotaurus, Ceratosaurus, Berthasaura
Six ceratosaurians (top to bottom): Rugops, Elaphrosaurus, Majungasaurus, Carnotaurus, Ceratosaurus, Berthasaura
Six ceratosaurians (top to bottom): Rugops, Elaphrosaurus, Majungasaurus, Carnotaurus, Ceratosaurus, Berthasaura
Six ceratosaurians (top to bottom): Rugops, Elaphrosaurus, Majungasaurus, Carnotaurus, Ceratosaurus, Berthasaura