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The Burgess Shale the Chengjiang

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The Burgess Shale the Chengjiang Cambrian Earth History The Paleozoic Era Cambrian Plate Tectonics The Cambrian “Explosion” The Burgess Shale The Chengjiang Fauna hp://www.cyberpiggy.com/ Copyright Greg Carter The Paleozoic The Paleozoic is the earliest, and longest, era of the Phanerozoic Eon. The Cambrian is the earliest period of the Paleozoic. All animal phyla with good fossil records (including chordates) first appear during the early Paleozoic, with almost all appearing during the Cambrian. Only one such animal phylum appears aer the Cambrian (bryozoans appear in the Ordovician). The end of the Paleozoic is punctuated by the largest mass exFncFon in Earth’s long history. Cambrian Proterozoic Proterozoic-Cambrian boundary Fortune Head, SE Newfoundland Dr. G. M. Narbonne points to the earliest occurrence of Trichophycus pedum h"p://www.uni-wuerzburg.de/palaeontologie/Stuff/casu11.htm Copyright (C) G. Geyer, 1997 Cambrian Plate Tectonics The Cambrian was a relatively quiet time for Laurentia, which drifted north toward the equator. The Avalon Island Arc, Baltica and Siberia were closing in on Laurentia, but wouldn’t arrive until later in the Paleozoic. The Carolina Terrane was forming well to the south, near the part of Gondwana that would eventually become Namibia. http://jan.ucc.nau.edu/~rcb7/510NAt.jpg hp://www.uky.edu/KGS/educaBon/images/ca_explo.gif The Cambrian Explosion animals without animals with skeletons skeletons “Sudden” appearance in the fossil record and rapid diversification of animals with hard parts http://www.palaeos.com/Paleozoic/Cambrian/Cambrian.htm The Cambrian “Explosion” in Animal Diversity Global Changes Why??? Fluctuating carbon isotopes Caused by changes in primary productivity? Difficult to interpret. Increase in oxygen Gradual increase continues, but no jump Increase ∂34S Tied to redox, complex interaction of tectonic and biochemical controls. Difficult to interpret. Increase in phosphorite production Complex causality, tied to redox. Difficult to interpret. http://www.palaeos.com/Paleozoic/Cambrian/Cambrian.htm Why??? Global Changes Rising sea level Increased amount of shallow water habitat Development of macro-predators Perhaps the skeletons were for protection. However, single- celled protists also develop skeletons, and not all skeletons would have worked as armor. Dozens of theories have been proposed, but no single theory has emerged as good enough to accept. New data is constantly being collected, so stay tuned… http://www.palaeos.com/Paleozoic/Cambrian/Cambrian.htm Early Cambrian Period Tommotian and Adtabanian Stages small, shelly fauna (SSF) Small calcite and apatite shells, bits, pieces, and other skeletal elements While many clearly came from known groups (e.g., mollusks), most can’t be assigned with certainty. Very abundant, global distribution. Basic Palaeontology . Benton M.J. & Harper D. 1997 Early Cambrian Period Tommotian and Adtabanian Stages small, shelly fauna (SSF) Insoluble residue of limestone samples with phosphatic tubes and sclerites of so-called "small shelly fossils". Late Tommotian, Malykan, Lena River, Siberia. Copyright (c) G. Geyer, 1997 http://www.uni-wuerzburg.de/palaeontologie/Stuff/casu8.htm The Middle Cambrian World Lagerstatten – a fossil Burgess Shale Chengjiang deposit of unusual quality, frequently “soft parts” are preserved. Greenland Three Tropical Lagerstatten http://www.nmnh.si.edu/paleo/ Middle Cambrian Lagerstatten Chengjiang� Burgess Shale http://www.palaeos.com/Paleozoic/Cambrian/Cambrian.htm Burgess Shale Algal Reef Occasional mudslides washed animals from oxygenated shallow water to anoxic basin http://www.burgess-shale.bc.ca/intro.htm Burgess Shale Animals preserved as fossils Animals with hard parts Stephen Mountain http://www.burgess-shale.bc.ca/ Walcott Quarry http://www.burgess-shale.bc.ca/ http://www-crewes.geo.ucalgary.ca/ Burgess Shale Fauna Included taxa that are obviously members of familiar groups as well as weird and wacky extinct groups http://www.dhushara.com/book/evol/edcamb.htm Phylum Arthropoda HUGE phylum Sidneyia Modern Isopod http://www.orgbio.pdx.edu/people/faculty.html http://www.nmnh.si.edu/paleo/ Canadapsis Marella Phylum Arthropoda HUGE phylum http://nmnhgoph.si.edu/paleo/shale/pfoslidx.htm Echmatocrinus Early crinoid Phylum Echinodermata Big phylum Komodo National Park, Indonesia Photographer: Ken Knezick http://www.dc.peachnet.edu/~pgore/geology/geo102/burgess/burgess.htm Phylum Brachiopoda minor phylum in modern ocean Paleozoic diversity high Micromitra Inarticulate brachiopod Diraphora Articulate brachiopod http://www.biology.ualberta.ca/courses.hp/zool250/ http://imperial.park.org/Canada/Museum/burgessshale/ Sponges Vauxia Phylum Porifera large phylum http://www.acmereef.com/ http://geo.ucalgary.ca/~macrae/Burgess_Shale/ Phylum Annelida: Class Polychaeta Very large class of worms Candida http://www.nmnh.si.edu/paleo/ http://www.dc.peachnet.edu/~pgore/geology/geo102/burgess/burgess.htm http://www.badmovies.org/othermovies/deeprising/ Ottoia Phylum Priapulida tiny phylum in modern ocean (~15 species) http://classes.seattleu.edu/biology/biol235/ http://www.nmnh.si.edu/paleo/ Superclass Trilobitomorpha Very large arthropod superclass, extinct at end of Paleozoic Hyolithids Trilobites Incerta sedis Hyolithida Small group of what might have been mollusks, extinct at end of Paleozoic http://www.nmnh.si.edu/paleo/ The weirdest of the weird turn out to be relatives of the modern onychophorans, or velvet worms ©1997 José A. Vargas Modern Phylum Onychophora 16 genera Aysheaia Hallucigenia http://rbt.ots.ac.cr/onych/photos/photos.htm http://nmnhgoph.si.edu/paleo/shale/pfoslidx.htm Hallucigenia Mary Parrish Reconstruction for the Smithsonian Museum of Natural History Hallucigenia http://www.nmnh.si.edu/paleo/PaleoArt Other Burgess Shale taxa defy categorization Wiwaxia http://nmnhgoph.si.edu/paleo/shale/pfoslidx.htm Opabinia Other Burgess Shale taxa defy categorization http://nmnhgoph.si.edu/paleo/shale/pfoslidx.htm Copyright Greg Carter Burgess Shale Melodrama Greg Carter Editorial illustration for Science Fiction Age magazine http://www.cyberpiggy.com/ Opabinia Mary Parrish Reconstruction for the Smithsonian Museum of Natural History http://www.nmnh.si.edu/paleo/PaleoArt Anomalocaris http://members.tripod.com/~Cambrian/ http://www.astrobiology.ucla.edu/ Other Burgess Shale taxa defy categorization Anomalocaris http://nicholnl.wcp.muohio.edu/NaturalSystems/NSEvolution3.html Anomalocaris Mary Parrish Reconstruction for the Smithsonian Museum of Natural History Anomalocaris http://www.nmnh.si.edu/paleo/PaleoArt Phylum Chordata Big phylum including vertebrates Amphioxus Pikaia The Burgess Shale fauna includes this small cephalochordate, a relative of the earliest chordate. http://news-info.wustl.edu/tips/2002/science-tech/vertebrate-invertebrate.html http://www.nmnh.si.edu/paleo/ http://www.dc.peachnet.edu/~pgore/geology/geo102/burgess/burgess.htm Chorus: It's a long way from amphioxus, it's a long way to us. It's a long way from amphioxus to the meanest human cuss. It's good-bye to fins and gill slits, and welcome lungs and hair. It's a long, long way from amphioxus, but we all came from there. Oh, a fish-like thing appeared among the annelids one day, It hadn't any parapods or setae to display. It hadn't any eyes or jaws or ventral nervous chord. But it had a lot of gill slits and it had a notochord. It wasn't much to look at and it scarce knew how to swim. And Nories was very sure it hadn't come from him. It's a Long The Molluscs wouldn't own it and the Arthropods got sore. So the poor thing had to burrow in the sand along the shore. Way From He burrowed in the sand before a crab could nip his tail. Amphioxus And he said, "Gill slits and myotomes are all to no avail." "I've grown some metapleural folds and sport an oral hood. But all these fine new characters don't do me any good." He sulked awhile down in the sand, without a bit of pep; Then he stiffened up his notochord and said, "I'll beat 'em yet!" "Let them laugh and show their ignorance, I don't mind their jeers." "Just wait until they see me in a hundred million years." "My notochord shall change into a chain of vertebra, And, as fins, my metapleural folds will agitate the sea." "My tiny dorsal nervous chord shall be a mighty brain. And the vertebrates shall dominate the animal domain." http://www.panix.com/~felicia/biopoem.html The Chengjiang fauna is an earlier Burgess Shale-like fauna, predating the Burgess Shale by ~12 Ma. http://palaeo.gly.bris.ac.uk/Palaeofiles/Lagerstatten/chngjang/ Uncertain Affiliations Eldonia eumorphia Sun & Hou, 1987. Facivermis yunnanicus Hou & Chen, 1989. The Chengjiang fauna Rotadiscus grandis Sun & Hou, 1987. added considerably to Xidazoon stephanus Shu, Conway Morris & Zhang, 1999. Dinomischus isolatus Conway Morris, 1977. the bestiary of the Cambrian Explosion Lobopodia Hallucigenia sparsa Walcott, 1911. Porifera (sponges) Cardiodictyon calenudum Hou, Ramsköld & Bergström, 1991. Crumillospongia frondosa Walcott, 1919. Hallucigenia fortis Hou & Bergstöm, 1995. Choia carteri Walcott, 1920. Luolishania conicruris Hou & Chen, 1989. Hazelia palmata Walcott, 1920. Microdictyon sinicum Chen, Hou & Lu, 1989. Leptomitus zitteli Walcott, 1886. Onychodictyon ferox Hou, Ramsköld & Bergström, 1991. Tabakkawia lineata Walcott, 1920. Paucipodia inermis Chen, Zhou & Ramsköld, 1995. Allantospongia mica Rigby & Hou, 1995. Choiaella radiata Rigby & Hou, 1995. Leptomitella metta Rigby, 1983. Leptomitus teretiusculus Chen, Hou & Lu, 1989. Paraleptomitella dictyodroma Chen, Hou & Lu,
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