Chinese Science Bulletin

, Volume 48, Issue 8, pp 725–735 | Cite as

A paleontological perspective of vertebrate origin

  • Degan ShuEmail author


The Early CambrianHaikouichthys and Haikouella have been claimed to be related to contribute in an important way to our understanding of vertebrate origin, but there have been heated debates about how exactly they are to be interpreted. New discoveries of numerous specimens ofHaikouichthys not only confirm the identity of previously described structures such as the dorsal and the ventral fins, and chevron-shaped myomeres, but also reveal many new important characteristics, including sensory organs of the head (e.g. large eyes), and a prominent notochord with differentiated vertebral elements. This “first fish” appears, however, to retain primitive reproductive features of acraniates, suggesting that it is a stem-group craniates. A. new order (Myllokunmingiida) and a new family (Myllokunmingiidae) are erected, and a new species,Zhongjianichthys rostratus (gen. et sp. nov.), is described herein. Over 1400 newlydiscovered specimens ofHaikouella provide a wealth of anatomical information on this organism. It differs from chordates in many organs and organ systems, including the skin, muscles, respiratory, circulatory and nervous systems. In contrast, its body-design resembles that of vetulicolians, and the presence of a “transitional” nervous system with both dorsal and ventral nerve cords suggests an affinity with living hemichordates. On the basis of these and other recent findings of fossil deuterostomes, a five-step hypothesis for vertebrate origin is proposed, intended to bridge the longstanding gap between protostomes and vertebrates. Four of the five steps accord with established ideas current in modern evolutionary zoology. Evidence for the first step is obtainable only from fossils, and specifically from fossils found from South China, hence the crucial importance of S. China sites for our understanding of early vertebrate origins and evolution. Accordingly, South China is suggested as the oldest-known birthplace of the whole vertebrates.


primitive vertebrateHaikouichthys non-chordateHaikouella Early Cambrian Chengjiang Lagerstatte origin of vertebrates deuterostome evolution 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Garstang, W., The morphology of the Tunicata and its bearing on the phylogeny of the Chordata, J. of the Microscopical Society, 1928, 72: 51–87.Google Scholar
  2. 2.
    Berrill, N. J., The Origin of Vertebrates, Oxford Oxford University Press, 1955.Google Scholar
  3. 3.
    Romer, A. S., The Vertebrate Story, Chicago: University of Chicago Press, 1971.Google Scholar
  4. 4.
    Schaeffer, B., Deuterostome monophyly and phylogeny, Evoln. Biol., 1987, 21: 179–235.Google Scholar
  5. 5.
    Gee, H., Deuterostome phylogeny: The context for the origin and evolution of the vertebrates, in Major Events in Early Vertebrate Evolution: Palaeontology, Phylogeny, Genetics and Development (ed Ahlberg, P. E.), London and New York: Taylor and Francis Inc., 2001.Google Scholar
  6. 6.
    Bromham, L. D., Degnan, B. M., Hemichordate and deuterostome evolution: robust molecular phylogenetic support for a hemichordate + echmoderm c Cameron, C. B., Garey, J. R, Swalla, B. X, Evolution of the chordate body plan: new insights from phylogenetic analyses of deuterostome phyla, Proc. Natl. Acad. Sci. USA, 2000, 97: 4469–4474.Google Scholar
  7. 8.
    Lacalli, T. C., Holland, N. D., West, J. E., ‘Landmarks m the anterior central nervous system of amphioxus larvae’, Phil. Trans. Royal Soc. Lond. B, 1994, 344: 165–485.CrossRefGoogle Scholar
  8. 9.
    Jefferies, R. P. S., The ancestry of the vertebrates. London, British Museum (Natural History), Cambridge: Cambridge University Press, 1986.Google Scholar
  9. 10.
    Jefferies, R. P. S., The origin and early fossil history of the chordate acustio-lateralis system, with remarks on the reality of the echinoderm-hemichordate clade, in Major Events in Early Vertebrate Evolution: Palaeontology, Phylogeny, Genetics and Development (ed Ahlberg, P. E.), London and New York: Taylor and Francis Inc., 2001.Google Scholar
  10. 11.
    Shu, D. G., Geyer, G., Chen, L. et al., Redlichiacean trilobites with preserved soft-parts from the Lower Cambrian Chengjiang fauna, Beringaria, Special Issue, 1995, 2: 203–241.Google Scholar
  11. 12.
    Shu, D. G., Zhang, X. L., Geyer, G., Anatomy and systematic affinities of Lower Cambrian bivalved arthropodIsoxys auritus, Alcheringa, 1995, 19: 333–342.CrossRefGoogle Scholar
  12. 13.
    Chen, J. Y., Zhou, G. Q., Biology of Chengjiang biota, Bull, Natl. Mus. Nat. Sci. Taiwan, 1997, 10: 11–405.Google Scholar
  13. 14.
    Hou, X. G., Bergstrom, I., Arthropods from the Lower Cambrian Changjiang Fauna, Sonthwest China, Fossils and Strata, 1997, 45: 1–115.Google Scholar
  14. 15.
    Shu, D., Vannier, J., Luo, H. et al. Anatomy and lifestyle of Kunmingella (Arthropoda, Bradoriida) from the Chengjiang fossil Lagerstatte (lower Cambrian; Southwest China), Lethaia, 1999, 32: 279–298.Google Scholar
  15. 16.
    Zhang, X. L., Shu, D., Li, Y. et al., New sites of Chengjiang fossils: crucial windows on the Cambrian explosion, J. Geol. Society, Lond, 2001, 158: 211–218.Google Scholar
  16. 17.
    Kardong, K., Vertebrates: Comparative Anatomy, Function, Evolution McGraw-Hill, Boston, 1997.Google Scholar
  17. 18.
    Shu, D., Zhang, X. L., Chen, L., Reinterpretation of Yunnanozoon as the earliest known hemichordate, Nature, 1996, 380: 428–430.CrossRefGoogle Scholar
  18. 19.
    Shu, D., Conway, M., S., Zhang, X. L., A. Pikaia-like chordate from the Lower Cambrian of China, Nature, 1996, 384: 157–458.CrossRefGoogle Scholar
  19. 20.
    Shu, D., Chen, L., Han, J. et al., The early Cambrian tunicate from South China, Nature, 2001, 411: 472–473.CrossRefGoogle Scholar
  20. 21.
    Shu, D., Chen, L., Han, J. et al., Chengjiang Lagerstatte and earliest-known chordates, Zoological Science, 2001, 18: 447–448.CrossRefGoogle Scholar
  21. 22.
    Chen, J. Y., Dzik, J., Edgecombe, G. D. et al., A. possible early Cambrian chordate, Nature, 1995, 377: 720–722.CrossRefGoogle Scholar
  22. 23.
    Chen, J., Huang, D. Y., Li, C. W., An Early Cambrian craniatelike chordate, Nature, 1999, 402: 518–521.CrossRefGoogle Scholar
  23. 24.
    Shu, D., Conway, M. S., Han, J. et al., Primitive deuterostomes from the Chengjiang Lagerstatte (Lower Cambrian, China), Nature, 2001, 414: 419–424.CrossRefGoogle Scholar
  24. 25.
    Shu, D., Conway, M. S., Zhang, X. et al, A. pipiscid-like fossil from the Lower Cambrian of South China, Nature, 1999, 400: 746–749.CrossRefGoogle Scholar
  25. 26.
    Shu, D., Luo, H., Conway, M. S. et al. Early Cambrian vertebrates from South China, Nature, 1999, 402: 42–46.CrossRefGoogle Scholar
  26. 27.
    Shu, D. G., Chen, L., Mosaic evolution of the earliest-known vertebrates, Geosciences (in Chinese with English abstract), 2000, 14: 315–322.Google Scholar
  27. 28.
    Shu, D. G., Conway, M. S., Han, X. et al. Head and Backbone of the Cambrian vertebrateHaikouichthys, Nature, 2003, 421: 526–529.CrossRefGoogle Scholar
  28. 29.
    Mueller, W. A., Developmental Biology, Beijing and Spring-Verlag Berlin Heidelberg, China Higher Education Press, 1998.Google Scholar
  29. 30.
    Janvier, P., Catching the first fish, Nature, 1999, 402: 21–22.CrossRefGoogle Scholar
  30. 31.
    Holland, H. D., Chen, J. Y., Origin and early evolution of the vertebrates: new insights from advances in molecular biology, anatomy, and palaeontology, BioEssays 2001, 23: 142–151.CrossRefGoogle Scholar
  31. 32.
    Jarvik, E., Basic Structure and Evolutionof Vertebrates, 2 vol. New York and London: Academic Press, 1980.Google Scholar
  32. 33.
    Cohn, M. J., Lamprey Hox genes and the origin of jaws, Nature, 2002, 416: 386–387.CrossRefGoogle Scholar
  33. 34.
    Bardack, D., Zangerl, R., Lamprey in the fossil record, The Biobgy of Lampreys (eds. Hardisty, M. W., Potter, I. C.), London: Academic Press, 1971, 1: 67–84.Google Scholar
  34. 35.
    Bardack, D., Richardson, E. S., New agnathous fishes from the Pennnsylvanian of Illinois, Fieldiana: Geology 1977, 33: 489–510.Google Scholar
  35. 36.
    Janvier, P., Early Vertebrates, Oxford Clarendon Press, 1996.Google Scholar
  36. 37.
    Dzik, J., Yunnanozoon and ancestry of chordates, Acta Palaeont, Polonica, 1995, 40: 341–360.Google Scholar
  37. 38.
    Hou, X. G., Ramskoeld, L., Bergstroem, J., Composition and preservation of the Chengjiang fauna—a Lower Cambrian softbodied biota, Zool, Scripta, 1991, 20: 395–411.CrossRefGoogle Scholar
  38. 39.
    Shu, D. G., Conway, M. S., Zhang, Z. F. et al, A. New Species of Yunnanozoans with Implications for Deuterostome Evolution, Science, 2003, 299: 1380–1384.CrossRefGoogle Scholar
  39. 40.
    Lacalli, T. C., Vetulicolians—are they deuterostomes? chordates? BioEssays, 2002, 24: 208–211.CrossRefGoogle Scholar
  40. 41.
    Gee, H., On thevetulicohans, Nature, 2001, 414: 407–409.CrossRefGoogle Scholar
  41. 42.
    Conway, M. S., The Crucible of Creation: The Burgess Shale and the Rise of Animals, Cambridge: Cambridge Univ. Press, 1998.Google Scholar
  42. 43.
    Bergestroem, J., Origin of high-rank groups of organisms, Paleontological Reserch, 1997, 1: 1–14.Google Scholar
  43. 44.
    Briggs, D. E. G., Kear, A. J., Decay of the lancelet Branchiostoma lanceolatum (Cephalochordata): implication for the interpretation of soft-tissue preservation in conodonts and other primitive chordates, Lethaia, 1994, 26: 275–287.CrossRefGoogle Scholar
  44. 45.
    Smith, M. P., Sansom, I. J., Cochrane, D., The Cambrian origin of vertebrates, in Major Events in Early Vertebrate Evolution: Palaeontology, Phylogeny, Genetics and Development (ed Ahlberg, P. E.), London and New York: Taylor and Francis Inc., 2001.Google Scholar
  45. 46.
    Harvey, Pough F., Heiser, J. B., McFarland, W. N., Vertebrate Life (Third edition), New York: MacMillan Pulbishing Company, 1989.Google Scholar
  46. 47.
    Luo, H. L., Hu, S. X., Chen, L. Z., New Early Cambrian chordates from Haikou, Kunming, Acta Geologica Sinica, 2001, 75: 345–348.Google Scholar
  47. 48.
    Gee, H., Before the Backbone: Views on the Origins of the Vertebrates. London, Chapman & Hall, 1996.Google Scholar
  48. 49.
    Nielsen, C., Animal Evolution: interrelationships of living phyla (2nd ed.), Oxford Oxford University Press, 2001.Google Scholar
  49. 50.
    Wada, H., Satoh, N., Details of the evolutionary history from invertebrates to vertebrates, as deduced from the sequences of 18S rDNA, Proc. Natl. Acad. Sci. USA, 1994, 91: 1801–4804.CrossRefGoogle Scholar
  50. 51.
    Paul, C. R. C., Evolution of primitive echinoderms, in Patterns of Evolution (ed Hallam, A.), Amsterdam: Eiservier Scientific Publ. Comp., 1977.Google Scholar
  51. 52.
    Luo, H. L., Hu, S. X., Chen, L. Z., Early Cambrian Chengjiang Fauna in Kunming Region (in Chinese with English summery), Kunming: Science and Technology Press of Yunnan Province, 1999.Google Scholar
  52. 53.
    Domingues, P., Jacobson, A. G., Jefferries, R. Paired gill slits in a fossil with a calcite skeleton, Nature, 2002, 417: 841–844.CrossRefGoogle Scholar
  53. 54.
    onway, M. S., Why molecular biology needs palaeontology, Development, 1994(Supp.): 1–13.Google Scholar
  54. 55.
    Ayala, F. J., Rzhetsky, A., Origin of metazoan phyla, Molecular clocks confirm palaeontological estimates, Proc. Natl. Acad. Sci., USA, 1998, 95: 606–611.CrossRefGoogle Scholar

Copyright information

© Science in China Press 2003

Authors and Affiliations

  1. 1.Early Life Institute & Department of GeologyNorthwest UniversityXi’anChina
  2. 2.School of Earth Sciences and ResourcesChina University of GeosciencesBeijingChina

Personalised recommendations