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Possible algal origin and life cycle of Ediacaran Doushantuo microfossils with dextral spiral structure

  • Xi-Guang Zhang (a1) and Brian R. Pratt (a2)
Abstract

In Ediacaran shallow-water dolomites of the Doushantuo Formation (ca. 570 Ma) of southern China, scarce phosphatized microfossils consisting of clusters of coil-like spheroids called Spiralicellula bulbifera and co-occurring spherical forms with helically arranged holes named Helicoforamina wenganica are interpreted to belong to the same taxon because both have a similar relative abundance and both, uniquely in the assemblage, exhibit a consistent dextral spiral feature—the oldest known fossil examples of fixed asymmetry. Thus, we interpret them as different stages of sexual and asexual life cycles in which the spiral structure was maintained throughout most of the developmental phases. While they can be placed with the acritarchs, we suggest they are a chlorophycean green alga, and like many Ediacaran macrofossils, may represent an extinct clade. This is compatible with the shoal-water marine depositional environment in which they lived, as it would have favored photosynthetic organisms over others kinds of encysting non-metazoan protists. This setting militates against their interpretation as putative embryos which has been put forward for a variety of forms co-occurring in the microfossil assemblage. The multiple affinities of the strikingly diverse biota remain far from resolved, but algal origins warrant further consideration.

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S. C. Agrawal 2009. Factors affecting spore germination in algae—review. Folia Microbiologica, 54:273302.

J. V. Bailey , S. B. Joye , K. M. Kalanetra , B. E. Flood , and F. A. Corsetti 2007a. Evidence of giant sulphur bacteria in Neoproterozoic phosphorites. Nature, 445:198201.

J. V. Bailey , S. B. Joye , K. M. Kalanetra , B. E. Flood , and F. A. Corsetti 2007b. Bailey et al. reply. Nature, 446:E10E11.

S. Bengtson and G. Budd 2004. Comment on “Small bilaterian fossils from 40 to 55 million years before the Cambrian”. Science, 306:1291.

S. Bengtson , J. A. Cunningham , C.-Y. Yin , and P. C. J. Donoghue 2012. A merciful death for the “earlist bilaterian,” Vernanimalcula . Evolution and Development, 14:421427.

S. Bengtson and Z. Yue 1997. Fossilized metazoan embryos from the earliest Cambrian. Science, 277:16451648.

N. J. Butterfield 2011. Terminal developments in Ediacaran embryology. Science, 334:16551656.

J.-Y. Chen , D. J. Bottjer , P. Oliveri , S. Q. Dornbos , F. Gao , S. Ruffins , H.-M. Chi , C.-W. Li , and E. H. Davidson 2004. Small bilaterian fossils from 40 to 55 million years before the Cambrian. Science, 305:218222.

P. A. Cohen , A. H. Knoll , and R. B. Kodner 2009. Large spinose microfossils in Ediacaran rocks as resting stages of early animals. Proceedings of the National Academy of Sciences, U.S.A., 106:65196524.

X.-P. Dong , P. C. J. Donoghue , H. Cheng , and J.-B. Liu 2004. Fossil embryos from the middle and late Cambrian period of Hunan, south China. Nature, 427:237240.

P. C. J. Donoghue 2007. Embryonic identity crisis. Nature, 445:155156.

S. Q. Dornbos , D. J. Bottjer , J.-Y. Chen , F. Gao , P. Oliveri , and C.-W. Li 2006. Environmental controls on the taphonomy of phosphatized animals and animal embryos from the Neoproterozoic Doushantuo Formation, southern China. Palaios, 21:314.

W. Edwards , A. T. Moles , and P. Franks 2007. The global trend in plant twining direction. Global Ecology and Biogeography, 16:795800.

N. J. Gostling , P. C. J. Donoghue , and S. Bengtson 1995. The earliest fossil embryos begin to mature. Evolution and Development, 9:206207.

H. R. Grenfell 1995. Probable fossil zygnematacean algal spore genera. Review of Paleobotany and Palynology, 84:201220.

J. W. Hagadorn , S.-H. Xiao , P. C. J. Donoghue , S. Bengtson , N. J. Gostling , M. Pawlowska , E. C. Raff , R. A. Raff , F. R. Turner , C.-Y. Yin , C.-M. Zhou , X.-L. Yuan , M. B. McFeely , M. Stampanoni , and K. H. Nealson 2006. Cellular and subcellular structure of Neoproterozoic embryos. Science, 314:291294.

M. D. Herron , A. G. Desnitskiy , and R. E. Michod 2010. Evolution of developmental programs in Volvox (Chlorophyta). Journal of Phycology, 46:316324.

T. Huldtgren , J. A. Cunningham , C.-Y. Yin , M. Stampanoni , F. Marone , P. C. J. Donoghue , and S. Bengtson 2011. Fossilized nuclei and germination structures identify Ediacaran “animal embryos” as encysting protists. Science, 334:16961699.

G.-Q. Jiang , X.-Y. Shi , S.-H. Zhang , Y. Wang , and S.-H. Xiao 2011. Stratigraphy and paleogeography of the Ediacaran Doushantuo Formation (ca. 635–551 Ma) in South China. Gondwana Research, 19:831849.

L. Mendoza , J. W. Taylor , and L. Ajello 2002. The Class Mesomycetozoea: a heterogeneous group of microorganisms at the animal-fungal boundary. Annual Review of Microbiology, 56:315344.

M. Moczydłowska 2011. The early Cambrian phytoplankton radiation: acritarch evidence from the Lükati Formation, Estonia. Palynology, 35:103145.

A. R. Palmer 2009. Animal asymmetry. Current Biology, 19:R473R477.

B. R. Pratt , M. M. Raviolo , and O. L. Bordonaro 2012. Carbonate platform dominated by peloidal sands: Lower Ordovician La Silla Formation of the eastern Precordillera, San Juan, Argentina. Sedimentology, 59:843866.

M. Schilthuizen and A. Davison 2005. The convoluted evolution of snail chirality. Naturwissenschaften, 92:504515.

C. Shen , B. R. Pratt , T. Lan , J.-B. Hou , L. Chen , B.-Q. Hao , and X.-G. Zhang 2013. The search for Orsten-type fossils in southern China. Palaeoworld, 22:19.

M. Steiner , M. Zhou , G. Li , Y. Qian , and B.-D. Erdtmann 2004. New Early Cambrian bilaterian embryos and larvae from China. Geology, 32:833836.

J. Sulek 1997. Variations of the surface sculpture and cell wall ultrastructure of the zygospores in Chlamydomonas geitleri (Chlorophyta). Botanica Acta, 110:444451.

W. A. Taylor and P. K. Strother 2008. Ultrastructure of some Cambrian palynomorphs from the Bright Angel Shale, Arizona, U.S.A. Review of Palaeobotany and Palynology, 151:4150.

S.-H. Xiao , J. W. Hagadorn , C.-M. Zhou , and X.-L. Yuan 2007a. Rare helical spheroidal fossils from the Doushantuo Lagerstätte: Ediacaran animal embryos come of age? Geology, 35:115118.

S.-H. Xiao and A. H. Knoll 2000. Phosphatized animal embryos from the Neoproterozoic Doushantuo Formation at Weng'an, Guizhou, South China. Journal of Paleontology, 74:767788.

S.-H. Xiao , C.-M. Zhou , and X.-L. Yuan 2007b. Undressing and redressing Ediacaran embryos. Nature, 446:E9E10.

S.-H. Xiao , A. H. Knoll , J. D. Schiffbauer , C.-M. Zhou , and X.-L. Yuan 2012. Comment on “Fossilized nuclei and germination structures identify Ediacaran ‘animal embryos' as encysting protists”. Science, 335:1169d.

S.-H. Xiao , A. H. Knoll , X.-L. Yuan , and C. M. Pueschel 2004. Phosphatized multicellular algae in the Neoproterozoic Doushantuo Formation, China, and the early evolution of florideophyte red algae. American Journal of Botany, 91:214227.

S.-H. Xiao , X.-L. Yuan , and A. H. Knoll 2000. Eumetazoan fossils in terminal Proterozoic phosphorites?: Proceedings of the National Academy of Sciences, U.S.A., 97:1368413689.

L.-M. Yin , M.-Y. Zhu , A. H. Knoll , X.-L. Yuan , J.-M. Zhang , and J. Hu 2007. Doushantuo embryos preserved inside diapause egg cysts. Nature, 446:661663.

X.-G. Zhang and B. R. Pratt 1994. Middle Cambrian arthropod embryos with blastomeres. Science, 266:637639.

X.-G. Zhang and B. R. Pratt 2008. Microborings in early Cambrian phosphatic and phosphatized fossils. Palaeogeography, Palaeoclimatology, Palaeoecology, 267:185195.

M. Zhu , J. G. Gehling , S. Xiao , Y. Zhao , and M. L. Droser 2008. Eight-armed Ediacara fossil preserved in contrasting taphonomic windows from China and Australia. Geology 36:867870.

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Journal of Paleontology
  • ISSN: 0022-3360
  • EISSN: 1937-2337
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