Burgess Shale 3422 226088874 2008-07-16T19:49:24Z Smith609 846901 /* Biota */ This incomplete, inaccuarte and unreferenced list is of limited use, and sustains the flawed "pigeon holing"/"shoehorning" approach. {{Infobox Rockunit | name = Burgess Shale | image = Marella.png | caption = ''[[Marella]]'', the most abundant Burgess Shale organism. | type = [[Geological formation]] | prilithology = [[Shale]] | otherlithology = | namedfor = [[Mount Burgess|Burgess Pass]] | namedby = [[Charles Doolittle Walcott]] | region = [[Yoho National Park]] | country = [[Canada]] | coordinates = | unitof = | subunits = | thickness = | extent = | area = | age = Middle [[Cambrian]]}} The '''Burgess Shale''' is famous for the exceptional preservation of the fossils preserved within it, in which the soft parts are preserved. A [[Cambrian]] black [[shale]] [[Geologic formation|formation]], it crops out in the [[Canadian Rockies]] of [[British Columbia]], [[Canada]]. It is in [[Yoho National Park]], near the town of [[Field, British Columbia|Field]] and is named after [[Mount Burgess|Burgess Pass]]. ==History and significance== The significance of the finds was not realised at the time of discovery; the [[trilobites]] found dated the fossils to the Middle [[Cambrian]] period, and Charles Walcott simply placed the unusual new species within the phyla known to exist during that period, a process [[Stephen Jay Gould]] dubbed "shoehorning" in his book about the Burgess Shale, ''[[Wonderful Life (book)|Wonderful Life]]'' (1989). A reinvestigation of the fossils in the 1980s by [[Harry Blackmore Whittington]], [[Derek Briggs]], and [[Simon Conway Morris]] of the [[University of Cambridge]], however, revealed that the fauna represented were much more diverse and unusual than Walcott had recognized. Indeed, many of the animals present had [[body form|bizarre anatomical features]] and only the sketchiest resemblance to other known animals. Examples include ''[[Opabinia]]'' with five eyes and a snout like a vacuum cleaner hose; ''[[Aysheaia]]'', which bears an extraordinary resemblance to a minor modern phylum — the [[Onychophora]]; ''[[Nectocaris]]'', which is apparently either a [[crustacean]] with fins or a [[vertebrate]] with a shell; and ''[[Hallucigenia]]'', which was originally reconstructed as walking on bilaterally symmetrical spines. Conway Morris now reconstructs it as another [[lobopod]], with the spines on its back. Several poorly understood fossils were found to be body parts of a large predatory organism known as ''[[Anomalocaris]]''. More recent (late 1990s) work by [[Derek Briggs]] and [[Richard Fortey]] has placed many of the "peculiar" Burgess Shale fossils as [[stem group]]s to the [[arthropod]]a, but many animals such as ''[[Amiskwia]]'' resist attempts to decipher their relationships to other groups. Gould's ''Wonderful Life'', published in 1989, popularized the Burgess Shale fossils. Gould suggests that the extraordinary diversity of the fossils indicate that life forms at the time were much more diverse than those that survive today and that many of the unique lineages were evolutionary experiments that became extinct. He suggests that this interpretation supports his hypothesis of [[evolution]] by [[punctuated equilibrium]]. However, over the ensuing years it became apparent that the diversity was similar to, if not a little lower than, today's; rather than erecting a new phylum for each new and unusual fossil find, researchers now attempt to deduce to which phylum they are most closely related. Gould's work has been criticised for what has been described as a hasty and incomplete analysis, used to support Gould's own ideas, and which has since entered the popular public consciousness.<ref>According to [[Derek Briggs]] and [[Richard Fortey]]. {{citation needed}} </ref> [[Image:ROM-BurgessShale-CompleteAnomalocarisFossil.png|thumb|left|The first complete ''[[Anomalocaris]]'' fossil found]] The diversity and exotic nature of the Burgess fauna (Middle Cambrian, 505 mya<ref>{{cite web | title = Age of Burgess Shale | url = http://palaeo.gly.bris.ac.uk/palaeofiles/lagerstatten/Burgess/Setting.html | work = Burgess Shale | publisher = Bristol University | accessdate = 2007-09-05}}</ref>) has caused a great deal of controversy in [[paleontology]] with regard to the reasons for and nature of the preceding period in the history of life that has come to be called the [[Cambrian Explosion]]. Further investigations showed that the Burgess Shale extends for many miles in isolated outcrops and the various faunas are preserved in different places. The deposits appear to represent small areas of muddy [[ocean]] bottom that — from time to time — slid down the face of a [[limestone]] cliff, [[turbidite]] flows by [[gravity current]]s, carrying their fauna and anything unfortunate enough to be swimming by into [[oxygen]]-poor waters in the depths. Six distinct faunal zones have been identified in the Burgess Shale. Now that scientists know what to look for, similar deposits have been identified elsewhere with similar faunas. The most important, similar deposits are even older turbidite flow deposits created in much the same way as the Burgess shales in [[Yunnan]] Province, [[China]]. These [[Maotianshan shales]] contain fauna quite similar to the Burgess. Due to its location within Yoho National Park, the shale is part of a [[UNESCO]] [[World Heritage Site]], specifically, the [[Canadian Rocky Mountain Parks]]. Subsequent exploration has found exposures of the shale over a front of several dozen kilometers and has identified at least six fossiliferous [[lagerstätten]] within the formation. ==Taphonomy and diagenesis== {{See|Burgess shale type preservation}} ''Please expand this section''<ref name=Butterfield1990>{{cite journal | url = http://links.jstor.org/sici?sici=0094–8373(199022)16%3A3%3C272%3AOPONOA%3E2.0.CO%3B2-%23 | author = Butterfield, N.J. | journal = Paleobiology | volume = 16 | issue = 3 | pages = 272–286 | year = 1990 | accessdate = 2008-06-22 | title=Organic Preservation of Non-Mineralizing Organisms and the Taphonomy of the Burgess Shale }}</ref><ref name=Butterfield2002>{{cite journal | doi = 10.1666/0094-8373(2002)028<0155:LGATIO>2.0.CO;2 | author = Butterfield, N.J. | journal = Paleobiology | volume = 28 | issue = 1 | pages = 155–171 | year = 2002 | title = ''Leanchoilia'' guts and the interpretation of three-dimensional structures in Burgess Shale-type fossils }}</ref><ref name=OrrEtAl1998>{{cite journal | url = http://www.sciencemag.org/cgi/content/abstract/281/5380/1173 | doi = 10.1126/science.281.5380.1173 | pmid = 9712577 | author = Orr, Patrick J.; Briggs, Derek E. G.; Kearns, Stuart L. | journal = Science | volume = 281 | issue = 5380 | pages = 1173 | year = 1998 | publisher = AAAS | title = Cambrian Burgess Shale Animals Replicated in Clay Minerals | accessdate = 2008-06-22 }}</ref><ref name=CARONEtAl2006>{{cite journal | doi = 10.2110/palo.2003.P05-070R | author = CARON, JEAN-BERNARD; JACKSON, DONALD A. | journal = PALAIOS | volume = 21 | issue = 5 | pages = 451–465 | year = 2006 | publisher = Society for Sedimentary Geology | title = Taphonomy Of The Greater Phyllopod Bed Community, Burgess Shale }}</ref><ref name=GainesEtAl2005>{{cite journal | url = http://linkinghub.elsevier.com/retrieve/pii/S003101820400584X | doi = 10.1016/j.palaeo.2004.07.034 | author = Gaines, R.R.; Kennedy, M.J.; Droser, M.L. | journal = Palaeogeography, Palaeoclimatology, Palaeoecology | volume = 220 | issue = 1–2 | pages = 193–205 | year = 2005 | publisher = Elsevier | title = A new hypothesis for organic preservation of Burgess Shale taxa in the middle Cambrian Wheeler Formation, House Range, Utah | accessdate = 2008-06-22 }}</ref><ref name=ButterfieldEtAl2007>{{cite journal | url = http://www.blackwell-synergy.com/doi/abs/10.1111/j.1475-4983.2007.00656.x | doi = 10.1111/j.1475-4983.2007.00656.x | author = Butterfield, N.J.; Balthasar, U.W.E.; Wilson, L.A. | journal = Palaeontology | volume = 50 | issue = 3 | pages = 537–543 | year = 2007 | publisher = Blackwell Synergy | title = Fossil Diagenesis In The Burgess Shale | accessdate = 2008-06-22 }}</ref> ==Biota== {{Main|Burgess shale type biota}} [[Image:Burgess scale2.png|thumb|[[Anomalocaris]], [[Laggania]], [[Opabinia]], [[Wiwaxia]], [[Pikaia]], and [[Hallucigenia]] compared.]] The following is a partial list of [[genus|genera]] by [[phylum]]. In this list, assignment to phyla is in many places inaccurate, out of date, arbitrary or plain wrong; see individual taxon pages for a fuller discussion of affinities. ==See also== * [[Body form]] * [[Fossil park]]s — protected fossiliferous sites world-wide * [[Invertebrate paleontology]] * [[History of invertebrate paleozoology]] * [[List of fossil sites]] ''(with link directory)'' * [[List of notable fossils]] * [[Micropaleontology]] * [[Paleobiology]] * [[Paleozoology]] * [[Treatise on Invertebrate Paleontology]] (50 volumes; 1953 to 2006, and continuing) * [[Science and technology in Canada]] == References == {{reflist|2}} ==Further reading== *Simon Conway Morris, ''The Crucible of Creation: The Burgess Shale and the Rise of Animals'', Oxford University Press, Oxford, 1998 (paperback 1999) ISBN 0-19-850197-8 (hbk), ISBN 0-19-286202-2 (pbk) *Richard Fortey, ''Trilobite: Eyewitness to Evolution'', Flamingo, 2001. ISBN 0-00-655138-6 *Stephen Jay Gould, ''Wonderful Life: Burgess Shale and the Nature of History'', Vintage, 2000. ISBN 0-09-927345-4 *Derek E. G. Briggs, Douglas H. Erwin, & Frederick J. Collier, ''The Fossils of the Burgess Shale'', Smithsonian, 1994. ISBN1-56098-364-7 ==Sources == *[http://www.burgess-shale.bc.ca/ The Burgess Shale Geoscience Foundation] — official website *[http://www.washington.edu/burkemuseum/bshale/index.html The Burgess Shale — Evolution's Big Bang] — Burke Museum of Natural History and Culture web pages resourcing an exhibition devoted to the Burgess Shale *[http://tabla.geo.ucalgary.ca/%7Emacrae/Burgess_Shale Burgess Shale Fossils] *[http://www.bbc.co.uk/radio4/history/inourtime/inourtime_20050217.shtml The Cambrian Explosion] — BBC Radio 4 broadcast, ''In Our Time'', [[17 February]] [[2005]], hosted by Melvyn Bragg (includes links to resource pages) *[[Stephen Jay Gould]] (1989), ''[[Wonderful Life|Wonderful Life: The Burgess Shale and the Nature of History]]'' (New York: [[W. W. Norton]]). This best-seller critiques Charles Doolittle Walcott's discovery; and it provides over two dozen illustrations of the [[metazoa]]ns found. *[http://paleodb.org/cgi-bin/bridge.pl?action=displayCollectionDetails&collection_no=215 Paleobiology Database The Burgess Shale (skeletonized fauna), Stephen Fm., British Columbia, Canada: St Davids, British Columbia] *[http://paleodb.org/cgi-bin/bridge.pl?action=displayCollectionDetails&collection_no=6854 Paleobiology Database Hanburia gloriosa, Phyllopod Bed, Burgess Shale, Canada — Whittington 1998: St Davids — Merioneth, British Columbia ] *[http://www.nmnh.si.edu/paleo/shale/pamsci.htm Smithsonian Museum] *[http://www.nmnh.si.edu/paleo/shale/pfoslidx.htm Species index from the Smithsonian Institution] {{World Heritage Sites in Canada}} {{coord|51|26|18|N|116|28|36|W|display=title|region:CA-BC_type:landmark_source:dewiki}} [[Category:Burgess Shale fossils]] [[Category:Cambrian]] [[Category:Yoho National Park]] [[Category:Paleontological sites]] [[Category:Geologic formations]] [[Category:Geology of the Rocky Mountains]] [[Category:Stratigraphy of Canada]] [[Category:Geology of British Columbia]] [[Category:Natural history of Canada]] [[ca:Esquists de Burgess]] [[de:Burgess-Schiefer]] [[es:Esquisto de Burgess]] [[eo:Skistejo Burgess]] [[fr:Schistes de Burgess]] [[it:Argillite di Burgess]] [[lt:Burgeso skalūnai]] [[nl:Burgess shale]] [[ja:バージェス頁岩]] [[pl:Łupki z Burgess]] [[pt:Folhelho Burgess]] [[fi:Burgess Shale]] [[sv:Burgess Shale]]