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Earth and Life pp 239-379 | Cite as

Evolutionary Scenario of the Early History of the Animal Kingdom: Evidence from Precambrian (Ediacaran) Weng’an and Early Cambrian Maotianshan Biotas, China

  • Jun-Yuan ChenEmail author
Part of the International Year of Planet Earth book series (IYPE)

Abstract

Late Proterozoic (Ediacaran) Weng’an (580 mya) and Early Cambrian Maotianshan (c. 530 mya) faunas of South China, illustrated here, document diverse body plans at phylum and subphylum level and confirm that bilaterians evolved well before the “Cambrian explosion”. The Weng’an faunas (from Guizhou), the oldest record of metazoans, consist mainly of embryos with possible affinities to living sponges, cnidarians, and bilaterians, but with adult specimens (though microscopic) of the same groups. The Maotianshan Shale faunas (from Yunnan), remarkably diverse at species level (over 100 species), have great diversity of metazoan body plans, many comparable with those of living groups. Because they occur at or near the evolutionary roots of many animal groups, intermediate forms are present. Evolution of Early Cambrian metazoans was surprisingly rapid. Worm-like ancestral euarthropods elucidate the evolutionary origins of the arthropods. The diverse Maotianshan vertebrates, representing “missing” history between an amphioxus-like ancestor and craniate vertebrates, provide an improved understanding of the early evolution of the vertebrates.

Keywords

China Guizhou Yunnan Chengjiang Latest Precambrian (Ediacaran)–Early Cambrian Doushantuo Formation (Weng’an phosphate member) Fossil embryos Maotianshan Shale (Early Cambrian) Panarthropod phylogeny Origin of Chordata and vertebrates (Cristozoa) Inception of vertebrate brain Phylogeny of Deuterostomia 

Notes

Acknowledgments

This work was supported by the National Basic Research Program of China (grants 2007CB815800 and 2006CB806400) and the National Science Foundation of China (grant 41023008). I thank John Talent, editor of this volume, for helpful comments and polishing the English of the manuscript; he and several assessors, including SQ Dornbos, Ruth Mawson, Peter Cockle, Janine Miller, and Karen Novotny, also contributed importantly to editing of the manuscript. Technical assistance was given by HZ Wu and XZ Li. This paper presents a wide coverage of research advanced by stimulating collaboration and discussion with many colleagues and former students, especially E Davidson, D Bottjer, MG Hadfield, L Gang, F Gang, and P Tafforeau on the Weng’an biota; J Mallat, D Waloszek, A Maas, MY Zhu, DY Huang, SQ Dornbos, J Vannier, N Holland, and SH Chuang on the Maotianshan Shale biota.

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© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.LPS Institute of Geology and Palaeontology of Academia SinicaNanjingPeople’s Republic of China
  2. 2.Institute of Evolution and Developmental Biology, Nanjing UniversityNanjingPeople’s Republic of China

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