Dinosauros emplumados

Na Galipedia, a Wikipedia en galego.
Impresión de Anchiornis , ilustrando as cores e disposición das plumas

Os dinosauros emplumados considéranse fósiles de transición entre dinosauros clásicos e aves. Era xa coñecido que as aves antigas como o Archaeopteryx tiñan moitas características de réptil, como dentes, e poutas nas súas dedas, e moitos anos antes teorizárase que os paxaros descendían de dinosauros terópodos. A finais dos anos 1990, os descubrimentos de dinosauros emplumados en China achegaron a proba concluínte da conexión, aínda que os detalles xenealóxicos aínda estean a ser dilucidados. Demostrouse de moitos xeitos a relación de descendencia entre aves e dinosauros, xa que a súa similitude morfolóxica en canto ao cranio, a cadeira, as patas e as extremidades superiores é moi notable. As aves son claramente monofiléticas e os seus primeiros representantes atópanse no Xurásico (Protoavis, un fósil controvertido do finais do Triásico, é considerado non aviano pola maioría dos paleontólogos).

Xéneros de dinosauros emplumados[editar | editar a fonte]

Dende 1996 até hoxe describíronse 21 xéneros de dinosauros non avianos con plumas ou protoplumas preservadas nos seus fósiles:

  1. Avimimus* (1987)[1][2]
  2. Sinosauropteryx (1996)[3]
  3. Protarchaeopteryx (1997)[4]
  4. Caudipteryx (1998)[5]
  5. Rahonavis* (1998)[6]
  6. Shuvuuia* (1999)[7]
  7. Sinornithosaurus (1999)[8]
  8. Beipiaosaurus (1999)[9]
  9. Microraptor (2000)[10]
  10. Nomingia* (2000)[11]
  11. Cryptovolans (2002)[12]
  12. Scansoriopteryx (2002)[13]
  13. Epidendrosaurus (2002)[14]
  14. Yixianosaurus (2003)[15]
  15. Dilong (2004)[16]
  16. Pedopenna (2005)[17]
  17. Jinfengopteryx (2005)[18][19]
  18. Sinocalliopteryx (2007)[20]
  19. Velociraptor* (2007)[21]
  20. Epidexipteryx (2008)[22]
  21. Anchiornis (2009)[23]

Notas[editar | editar a fonte]

  1. Kurzanov, S.M. (1987). "Avimimidae and the problem of the origin of birds." Transactions of the Joint Soviet-Mongolian Paleontological Expedition, 31: 5-92. [in Russian]
  2. Chiappe, L.M. and Witmer, L.M. (2002). Mesozoic Birds: Above the Heads of Dinosaurs. Berkeley: University of California Press, 536 pp. ISBN 0-520-20094-2
  3. Ji, Q., and Ji, S. (1996). "On discovery of the earliest bird fossil in China and the origin of birds." Chinese Geology 10 (233): 30-33.
  4. Ji, Q., and Ji, S. (1997). "A Chinese archaeopterygian, Protarchaeopteryx gen. nov." Geological Science and Technology (Di Zhi Ke Ji), 238: 38-41. Translated By Will Downs Bilby Research Center Northern Arizona University January, 2001
  5. Qiang, J., .Currie, P.J., Norell., M.A. & Shu-An, J., 1998. Two feathered dinosaursfrom northeastern China. Nature 393 753-761.
  6. Forster, Catherine A.; Sampson, Scott D.; Chiappe, Luis M. & Krause, David W. (1998a). «The Theropod Ancestry of Birds: New Evidence from the Late Cretaceous of Madagascar». Science (5358): pp. 1915–1919.  . doi 10.1126/science.279.5358.1915 (HTML abstract)
  7. Schweitzer, Mary Higby, Watt, J.A., Avci, R., Knapp, L., Chiappe, L, Norell, Mark A., Marshall, M. (1999). "Beta-Keratin Specific Immunological reactivity in Feather-Like Structures of the Cretaceous Alvarezsaurid, Shuvuuia deserti Journal of Experimental Biology (Mol Dev Evol) 255:146-157
  8. Xu, X., Wang, X., Wu, X., 1999. A dromaeosaurid dinosaur with a filamentous integument from the Yixian Formation of China. Nature 401:6750 262-266 doi 10.1038/45769
  9. Xu. X., Zhao, X., Clark, J.M., 1999. A new therizinosaur from the Lower Jurassic lower Lufeng Formation of Yunnan, China. Journal of Vertebrate Paleontology 21:3 477–483 doi 10.1671/0272-4634
  10. Xu, X., Zhou, Z., and Wang, X. (2000). "The smallest known non-avian theropod dinosaur." Nature, 408 (December): 705-708.[1]
  11. Barsbold, R., Osmólska, H., Watabe, M., Currie, P.J., and Tsogtbaatar, K. (2000). "New Oviraptorosaur (Dinosauria, Theropoda) From Mongolia: The First Dinosaur With A Pygostyle". Acta Palaeontologica Polonica, 45(2): 97-106.
  12. Czerkas, S.A., Zhang, D., Li, J., and Li, Y. (2002). «Flying Dromaeosaurs». En Czerkas, S.J. Feathered Dinosaurs and the Origin of Flight: The Dinosaur Museum Journal 1. Blanding: The Dinosaur Museum. pp. 16–26. 
  13. Czerkas, S.A., and Yuan, C. (2002). "An arboreal maniraptoran from northeast China." Pp. 63-95 in Czerkas, S.J. (Ed.), Feathered Dinosaurs and the Origin of Flight. The Dinosaur Museum Journal 1. The Dinosaur Museum, Blanding, U.S.A. PDF abridged version
  14. Zhang, F., Zhou, Z., Xu, X. & Wang, X. (2002). "A juvenile coelurosaurian theropod from China indicates arboreal habits." Naturwissenschaften, 89(9): 394-398. doi=10.1007 /s00114-002-0353-8.
  15. Xu, X. and Wang, X.-L. (2003). "A new maniraptoran from the Early Cretaceous Yixian Formation of western Liaoning." Vertebrata PalAsiatica, 41(3): 195–202.
  16. Xu, X., Norell, M. A., Kuang, X., Wang, X., Zhao, Q., Jia, C. (2004). «Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids». Nature 431: 680–684. doi:10.1038/nature02855. 
  17. Xu, X., and Zhang, F. (2005). "A new maniraptoran dinosaur from China with long feathers on the metatarsus." Naturwissenschaften, 92(4): 173 - 177.
  18. Ji, Q., Ji, S., Lu, J., You, H., Chen, W., Liu, Y., and Liu, Y. (2005). "First avialan bird from China (Jinfengopteryx elegans gen. et sp. nov.)." Geological Bulletin of China, 24(3): 197-205.
  19. Turner, Alan H.; Pol, Diego; Clarke, Julia A.; Erickson, Gregory M.; and Norell, Mark (2007). «A basal dromaeosaurid and size evolution preceding avian flight» (pdf). Science 317: 1378–1381. doi:10.1126/science.1144066. PMID 17823350. 
  20. Ji, S., Ji, Q., Lu J., and Yuan, C. (2007). "A new giant compsognathid dinosaur with long filamentous integuments from Lower Cretaceous of Northeastern China." Acta Geologica Sinica, 81(1): 8-15.
  21. Turner, A.H.; Makovicky, P.J.; and Norell, M.A. (2007). «Feather quill knobs in the dinosaur Velociraptor» (pdf). Science 317 (5845): 1721. doi:10.1126/science.1145076. PMID 17885130. 
  22. Zhang, F., Zhou, Z., Xu, X., Wang, X., & Sullivan, C. (2008). "A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers." Available from Nature Precedings, doi:10.1038/npre.2008.2326.1 [2].
  23. Xu, X., Zhao, Q., Norell, M., Sullivan, C., Hone, D., Erickson, G., Wang, X., Han, F. and Guo, Y. (in press). "A new feathered maniraptoran dinosaur fossil that fills a morphological gap in avian origin." Chinese Science Bulletin, 6 pages, accepted November 15, 2008.