Journal of Ornithology

, Volume 153, Issue 3, pp 699–711 | Cite as

The evolution of the feather: Sinosauropteryx, life, death and preservation of an alleged feathered dinosaur

Original Article

Abstract

Among the spectacular dinosaur fossils reported from the Jehol Group of northeastern China is the most celebrated, Sinosauropteryx, which continues to excite interest in questions concerning feather origins—most recently with alleged identifications of melanosomes and colour in its integumental structures, which proved unfounded. The crucial significance of Sinosauropteryx is undoubtedly the focus on its basal theropod status and potentially pivotal position in informing models of the early evolutionary origin of modern feathers. On the basis of new evidence in Sinosauropteryx NIGP 127587 and GMV 2124, it is shown here that the alleged protofeathers were not free filaments but part of a composite tissue. It is shown that the tail terminates in a unique, smoothly edged, spatula-shaped structure. The dinosaurs died in the vicinity of a lake. For the first time, the taphonomy of Sinosauropteryx is investigated on the basis of aboveground decomposition experiments on living animals so as to get a better understanding of conditions preceding the death of the animal, its death, decomposition and finally preservation of soft tissue as manifested in the fossil. The signs point strongly to invertebrate colonization of the carcass of Sinosauropteryx rather than vertebrate predation or scavenging, with moderate decay associated with the purge fluids while major decay was forestalled by burial, at most a few days after death. Lastly, a theory that the opisthotonic posture of fossils such as Sinosauropteryx NIGP 127587 occurred perimortem as a consequence of neural spasms provides the basis for a forensic reconstruction of the stages leading to the dinosaur’s death and the final preserved position of the external, dorsally preserved soft tissue, which proves to be more consistent with a uniform crest than individual, free protofeathers.

Keywords

Sinosauropteryx Protofeathers or dorsal crest Taphonomy Decomposition experiments Forensic animation Perimortem opisthotonus 

Zusammenfassung

Die Evolution der Feder:Sinosauropteryx—Leben, Tod und Konservierung eines mutmaßlich befiederten Dinosauriers

Unter den spektakulären Dinosaurierfossilien, die in der Jehol-Gruppe in Nordostchina gefunden wurden, befindet sich der berühmte Sinosauropteryx, der nach wie vor Interesse an Fragen zum Ursprung der Feder hervorruft. Kürzlich wurden mutmaßliche Melanosomen und Farbe in den Integumentstrukturen identifiziert, was sich jedoch als nicht zutreffend erwies. Die entscheidende Bedeutung von Sinosauropteryx hat sich zweifellos auf seinen Status als basaler Theropode und seinen potenziell ausschlaggebenden Informationswert für Modelle des frühen evolutionären Ursprungs moderner Federn konzentriert. Anhand neuer Befunde bei Sinosauropteryx NIGP 127587 und GMV 2124 zeigen wir hier, dass die mutmaßlichen Protofedern nicht freie Filamente, sondern Teil eines Mischgewebes waren. Des Weiteren wird gezeigt, dass der Schwanz in einer einzigartigen glattrandigen spatelförmigen Struktur endet. Darüber hinaus wird die Taphonomie von Sinosauropteryx anhand von oberirdischen Verwesungsexperimenten mit lebenden Tieren untersucht, um ein besseres Verständnis der Bedingungen, die dem Tod des Tieres vorausgingen, seines Todes, seiner Verwesung und schließlich der Konservierung weichen Gewebes, wie es sich im Fossil offenbart, zu erlangen. Die Indizien deuten stark darauf hin, dass der Kadaver von Sinosauropteryx nicht Prädation oder Aasfraß durch Wirbeltiere ausgesetzt war, sondern von Wirbellosen besiedelt wurde—moderate Verwesung stand mit Zutritt von Flüssigkeiten in Zusammenhang, während starke Verwesung durch Bedeckung des Kadavers höchstens wenige Tage nach dem Tod verhindert wurde. Schließlich lieferte eine Theorie, gemäß derer die opisthotone Haltung von Fossilien wie Sinosauropteryx NIGP 127587 als Folge neuraler Spasmen während des Todes auftrat, die Grundlage für eine forensische Rekonstruktion der Stadien, die zum Tod des Dinosauriers führten, und der endgültigen konservierten Position des äußeren dorsal konservierten Weichgewebes, was eher mit einer uniformen Haube als mit einzelnen freien Protofedern übereinstimmt.

Supplementary material

10336_2011_787_MOESM1_ESM.gif (4 mb)
Supplemental Movie. 1 (GIF 4.02 mb)
10336_2011_787_MOESM4_ESM.mp4 (4.6 mb)
Supplemental Movie. 2 (GIF 8.15 mb)
10336_2011_787_MOESM2_ESM.gif (4.9 mb)
Supplemental Movie. 3 (GIF 4.92 mb)
10336_2011_787_MOESM3_ESM.gif (8.2 mb)
Movie 4. Forensic animation showing stages in the perimortem “death throes” of Sinosauropteryx NIGM 127587 ending in the opisthotonic posture (Fig. 1). The animation includes the suggested environment of volcanic eruptions and emissions of clouds of gasses (see text) that apparently led to the poisoning and death of this dinosaur. (GIF 8349 kb)

References

  1. Amendt J, Krettek R, Zehner R (2004) Forensic entomology. Naturwissenscaften 91:51–65CrossRefGoogle Scholar
  2. Blagoderov VA, Lukashevich ED, Mostovski MB (2002) Order Diptera Linne, 1758. The true flies. In: Rasnitsyn AP, Quicke DLJ (eds) History of insects. Kluwer, London, pp 227–240Google Scholar
  3. Britt BB, Scheetz RD, Dangerfield A (2008) A suite of dermestid beetle traces on dinosaur bone from the Upper Jurassic Morrison Formation, Wyoming, USA. Ichnos 15(2):59–71CrossRefGoogle Scholar
  4. Carter DO, Yellowlees D, Tibbett M (2007) Cadaver decomposition in terrestrial ecosystems. Naturwissenschaften 94:12–24PubMedCrossRefGoogle Scholar
  5. Chen P-J, Dong ZM, Zheng SN (1998) An exceptionally well preserved theropod dinosaur from the Yixian Formation of China. Nature 391:147–152CrossRefGoogle Scholar
  6. Chuong C-M, Chodankar R, Widelitz RB, Jiang T-X (2000) Evo-Devo of feathers and scales: building complex epithelial appendages. Curr Opin Genet Dev 10:449–456PubMedCrossRefGoogle Scholar
  7. Clark RB, Cowey JB (1958) Factors controlling the change of shape of certain nemertean and turbellarian worms. J Exp Biol 35:731–748Google Scholar
  8. Currie PJ, Chen P-J (2001) Anatomy of Sinosauropteryx prima from Liaoning, northeastern China. Can J Earth Sci 38:1705–1727CrossRefGoogle Scholar
  9. Duncan RM, Jensen WI (1976) A relationship between avian carcasses and living invertebrates in the epizootiology of avian botulism. J Wildl Dis 12(1):116–126Google Scholar
  10. Efremov EA (1940) Taphonomy: a new branch of paleontology. Pan Am Geol 74:81–93Google Scholar
  11. Faux CM, Padian K (2007) The opisthotonic posture of vertebrate skeletons: postmortem contraction or death throes? Paleobiology 33(2):201–226CrossRefGoogle Scholar
  12. Feduccia A, Lingham-Soliar T, Hinchcliffe JR (2005) Do feathered dinosaurs exist? Testing the hypothesis on neontological and paleontological evidence. J Morphol 266:125–166PubMedCrossRefGoogle Scholar
  13. Ji Q, Ji S (1997) Advances in Sinosauropteryx research. Chin Geol 7:30–32Google Scholar
  14. Ji S, Gao C, Liu J, Meng Q, Ji Q (2007) New material of Sinosauropteryx (Theropoda: Compsognathidae) from western Liaoning, China. Acta Geologica Sinica (English Edition) 81(2):177–182Google Scholar
  15. Lewis JL, Johnson SL (2001) Collagen architecture and failure processes in bovine patellar cartilages. J Anat 199:483–492PubMedCrossRefGoogle Scholar
  16. Lingham-Soliar T (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni (Mosasauridae, Reptilia) from the Upper Cretaceous, Upper Maastrichtian of the Netherlands. Phil Trans R Soc Lond B 347:155–180CrossRefGoogle Scholar
  17. Lingham-Soliar T (2003) The dinosaurian origin of feathers: perspectives from dolphin (Cetacea) collagen fibres. Naturwissenschaften 90:563–567PubMedCrossRefGoogle Scholar
  18. Lingham-Soliar T (2005a) Dorsal fin in the white shark Carcharodon carcharias: a dynamic stabilizer for fast swimming. J Morphol 263:1–11PubMedCrossRefGoogle Scholar
  19. Lingham-Soliar T (2005b) Caudal fin in the white shark, Carcharodon carcharias (Lamnidae): a dynamic propeller for fast, efficient swimming. J Morphol 264:233–252PubMedCrossRefGoogle Scholar
  20. Lingham-Soliar T (2008) A unique cross-section through the skin of the dinosaur Psittacosaurus from China showing a complex fibre architecture. Proc R Soc Lond B 275:775–780. doi:10.1098/rspb.2007.1342 CrossRefGoogle Scholar
  21. Lingham-Soliar T (2010a) Dinosaur protofeathers: pushing back the origin of feathers into the Middle Triassic? J Ornithol 151:193–200. doi:10.1007/s10336-009-0446-7 CrossRefGoogle Scholar
  22. Lingham-Soliar T (2010b) Response to comments by G. Mayr to my paper ‘‘Dinosaur protofeathers: pushing back the origin of feathers into the Middle Triassic?’’. J Ornithol 151:519–521. doi:10.1007/s10336-009-0475-2 CrossRefGoogle Scholar
  23. Lingham-Soliar T (2011) The evolution of the feather: Sinosauropteryx, a colourful tail. J Ornithol 152(3):567–577. doi:10.1007/s10336-010-0620-y CrossRefGoogle Scholar
  24. Lingham-Soliar T, Glab J (2010) Dehydration: a mechanism for the preservation of fine detail in fossilised soft tissue of ancient terrestrial animals. Palaeogeogr Palaeoclimatol Palaeoecol 291:481–487. doi:10.1016/j.palaeo.2010.03.019 CrossRefGoogle Scholar
  25. Lingham-Soliar T, Plodowski G (2010) The integument of Psittacosaurus from Liaoning Province, China: taphonomy, epidermal patterns and color of a ceratopsian dinosaur. Naturwissenschaften 97:479–486. doi:10.1007/s00114-010-0661-3 PubMedCrossRefGoogle Scholar
  26. Lingham-Soliar T, Feduccia A, Wang X (2007) A new Chinese specimen indicates that ‘protofeathers’ in the early Cretaceous theropod dinosaur Sinosauropteryx are degraded collagen fibres. Proc R Soc Lond B 274:1823–1829. doi:10.1098/rspb.2007.0352 CrossRefGoogle Scholar
  27. Lingham-Soliar T, Bonser RHC, Wesley-Smith J (2010) Selective biodegradation of keratin matrix in feather rachis reveals classic bioengineering. Proc R Soc Lond B 277:1161–1168. doi:10.1098/rspb.2009.1980 CrossRefGoogle Scholar
  28. Linnaeus C (1767) Systema naturae, 12th edn. Laurentius Salvius, StockholmGoogle Scholar
  29. Manning PL, Morris PM, McMahon A, Jones E, Gize A, Macquaker JHS, Wolff G, Thompson A, Marshall J, Taylor KG et al (2009) Mineralized soft-tissue structure and chemistry in a mummified hadrosaur from the Hell Creek Formation, North Dakota (USA). Proc R Soc Lond B 276:3429–3437. doi:10.1098/rspb.2009.0812 CrossRefGoogle Scholar
  30. Mayr G, Peters DS, Plodowski G, Vogel O (2002) Bristle-like integumentary structures at the tail of the horned dinosaur Psittacosaurus. Naturwissenschaften 89:361–365PubMedCrossRefGoogle Scholar
  31. Monroe JS, Wicander R (2009) The changing earth: exploring geology and evolution. Brooks/Cole, BelmontGoogle Scholar
  32. Pabst DA (1996) Morphology of the subdermal connective sheath of dolphins: a new fibre-wound, thin-walled, pressurized cylinder model for swimming vertebrates. J Zool 238:35–52CrossRefGoogle Scholar
  33. Payne JA (1965) A summer carrion study of the baby pig Sus scrofa Linneaus. Ecology 46:592–602CrossRefGoogle Scholar
  34. Prum RO, Brush AH (2003) Which came first, the feather of the bird? Sci Am 288:86–93Google Scholar
  35. Schoenly K, Reid W (1987) Dynamics of heterotrophic succession in carrion arthropod assemblages: discreet series or a continuum of change. Oecologia 73:192–202CrossRefGoogle Scholar
  36. Wainwright SA, Vosburgh F, Hebrank JH (1978) Shark skin function in locomotion. Science 202:747–749PubMedCrossRefGoogle Scholar
  37. Xu X, Zhou H, Prum RO (2001) Branched integumental structures in Sinornithosaurus and the origin of birds. Nature 410:200–204PubMedCrossRefGoogle Scholar
  38. Zhang F, Zhou Z, Dyke G (2006) Feathers and‘feather-like’ integumentary structures in Liaoning birds and dinosaurs. Geol J 41:395–404. doi:10.1002/gj.1057 CrossRefGoogle Scholar
  39. Zhang F, Kearns SL, Orr PJ, Benton MJ, Zhou Z, Johnson D, Xu X, Wang X (2010) Fossilized melanosomes and the colour of Cretaceous dinosaurs and birds. Nature 463:1075–1078. doi:10.1038/nature08740 PubMedCrossRefGoogle Scholar
  40. Zhou Z, Barrett PM, Hilton J (2003) An exceptionally preserved Lower Cretaceous ecosystem. Nature 421:807–814PubMedCrossRefGoogle Scholar

Copyright information

© Dt. Ornithologen-Gesellschaft e.V. 2011

Authors and Affiliations

  1. 1.Department of Biological and Conservation SciencesUniversity of KwaZulu-NatalWestville, DurbanSouth Africa

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