Extraordinary fossils reveal the nature of Cambrian life: a commentary on Whittington (1975) ‘The enigmatic animal
            Opabinia regalis
            , Middle Cambrian, Burgess Shale, British Columbia’

Harry Whittington's 1975 monograph on Opabinia was the first to highlight how some of the Burgess Shale animals differ markedly from those that populate today's oceans. Categorized by Stephen J. Gould as a ‘weird wonder’ ( Wonderful life , 1989) Opabinia , together with other unusual Burgess Shale fossils, stimulated ongoing debates about the early evolution of the major animal groups and the nature of the Cambrian explosion. The subsequent discovery of a number of other exceptionally preserved fossil faunas of Cambrian and early Ordovician age has significantly augmented the information available on this critical interval in the history of life. Although Opabinia initially defied assignment to any group of modern animals, it is now interpreted as lying below anomalocaridids on the stem leading to the living arthropods. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society .

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The “evolution” of Anomalocaris and its classification in the arthropod class Dinocarida (nov.) and order Radiodonta (nov.)

Journal of Paleontology ◽

10.1017/s0022336000023362 ◽

1996 ◽

Vol 70 (2) ◽

pp. 280-293 ◽

Cited By ~ 92

Author(s):

Desmond Collins

Keyword(s):

British Columbia ◽

Sea Cucumber ◽

Great Difficulty ◽

Burgess Shale ◽

Middle Cambrian ◽

The Past ◽

History Of ◽

The Many ◽

Life On Earth ◽

Mistaken Identification

The remarkable “evolution” of the reconstructions of Anomalocaris, the extraordinary predator from the 515 million year old Middle Cambrian Burgess Shale of British Columbia, reflects the dramatic changes in our interpretation of early animal life on Earth over the past 100 years. Beginning in 1892 with a claw identified as the abdomen and tail of a phyllocarid crustacean, parts of Anomalocaris have been described variously as a jellyfish, a sea-cucumber, a polychaete worm, a composite of a jellyfish and sponge, or have been attached to other arthropods as appendages. Charles D. Walcott collected complete specimens of Anomalocaris nathorsti between 1911 and 1917, and a Geological Survey of Canada party collected an almost complete specimen of Anomalocaris canadensis in 1966 or 1967, but neither species was adequately described until 1985. At that time they were interpreted by Whittington and Briggs to be representatives of “a hitherto unknown phylum.”Here, using recently collected specimens, the two species are newly reconstructed and described in the genera Anomalocaris and Laggania, and interpreted to be members of an extinct arthropod class, Dinocarida, and order Radiodonta, new to science. The long history of inaccurate reconstruction and mistaken identification of Anomalocaris and Laggania exemplifies our great difficulty in visualizing and classifying, from fossil remains, the many Cambrian animals with no apparent living descendants.

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Lower Cambrian pediculate lingulids from Yunnan, China

Journal of Paleontology ◽

10.1017/s0022336000037057 ◽

1993 ◽

Vol 67 (5) ◽

pp. 788-798 ◽

Cited By ~ 34

Author(s):

Jin Yugan ◽

Hou Xianguang ◽

Wang Huayu

Keyword(s):

New York ◽

British Columbia ◽

Lower Cambrian ◽

Structure And Function ◽

The Other ◽

Burgess Shale ◽

Middle Cambrian ◽

Middle Ordovician ◽

Early Ordovician ◽

And Function

The vermiform pedicle is one of the most distinctive organs of modern lingulids, but it is rarely preserved. Only two fossil specimens of lingulids with pedicle casts have been reported, one from the Ordovician and the other from the Devonian. No record of fossil pedicles of Lingulella and Lingulepis, the dominant Cambrian and Early Ordovician lingulids, is known. Fossil lingulids from the Lower Cambrian of Chengjiang County, Yunnan, suggest that the structure and function of the pedicle of the lingulids has not changed significantly from its first appearance. A comparison of fossil pedicle of lingulids from the Lower Cambrian, Chengjiang County (China), the Burgess Shale, Middle Cambrian, British Columbia (Canada), the Trenton Formation, Middle Ordovician, New York (U.S.A.), and the Devonian, Devonshire (England, U.K.) shows that the delthyrial area to which the pedicle muscles are attached was reduced in length through time until these muscles were completely embraced by the two valves.Two species, Lingulella chengjiangensis n. sp. and Lingulepis malongensis Rong, are described.

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A new helcionelloid mollusk from the middle Cambrian Burgess Shale, Canada

Journal of Paleontology ◽

10.1666/13-050 ◽

2013 ◽

Vol 87 (6) ◽

pp. 1067-1070 ◽

Cited By ~ 4

Author(s):

Simon Conway Morris ◽

John S. Peel

Keyword(s):

British Columbia ◽

New Species ◽

Cambrian Explosion ◽

Burgess Shale ◽

Middle Cambrian ◽

Marine Life ◽

A New Species

Burgess Shale-type faunas provide unique insights into the Cambrian “explosion”. Their degree of representativeness of Cambrian marine life in general is, however, less easy to establish. One line of evidence is to consider only the skeletal component of a Burgess Shale-type fauna and compare that with a typical Cambrian assemblage. This paper describes a new species of helcionelloid mollusk (Totoralia reticulata n. sp.) from the middle Cambrian Burgess Shale of British Columbia. Whilst much rarer than the co-occurring smooth shelled helcionelloid Scenella amii, the strongly costate morphology of Totoralia reinforces comparisons with Cambrian shelly faunas. The extension of the range of Totoralia from Argentina to Canada adds support to the proposed derivation of the Precordillera terrane of Mendoza from Laurentia.

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A new Late Silurian (Pridolian) naraoiid (Euarthropoda: Nektaspida) from the Bertie Formation of southern Ontario, Canada—delayed fallout from the Cambrian explosion

Journal of Paleontology ◽

10.1017/s0022336000043948 ◽

2004 ◽

Vol 78 (6) ◽

pp. 1138-1145 ◽

Cited By ~ 10

Author(s):

Jean-Bernard Caron ◽

David M. Rudkin ◽

Stuart Milliken

Keyword(s):

Late Ordovician ◽

Cambrian Explosion ◽

Burgess Shale ◽

Soft Bottom ◽

Southern Ontario ◽

Middle Cambrian ◽

Holotype Specimen ◽

Extinction Events ◽

Lazarus Effect ◽

Mass Extinction Events

The discovery of a new naraoiid nektaspid in the Upper Silurian (Pridolian) of southeastern Ontario significantly extends the range of this unusual group. Nektaspids are nonmineralized arthropods typical of Early and Middle Cambrian soft-bottom communities, but were thought to have become extinct in the Late Ordovician. The unique holotype specimen of Naraoia bertiensis n. sp. comes from a Konservat–Lagerstätte deposit renowned for its eurypterid fauna (the Williamsville Member of the Bertie Formation). Naraoia bertiensis lacks thoracic segments and is morphologically similar to Naraoia compacta from the Middle Cambrian Burgess Shale, save for the presence of a long ventral cephalic doublure and a subtly pointed posterior shield. To examine the phylogenetic relationships of the new naraoiid, we coded characters of the holotype specimen and of nine previously described nektaspids. The results confirm a sister taxon relationship between Naraoia compacta and Naraoia bertiensis and the monophyly of nektaspid forms lacking thoracic segments (family Naraoiidae). This latter group may have arisen from an ancestral segment-bearing form through heterochronic loss of thoracic segments early in the Cambrian. The disjunct occurrence of a naraoiid nektaspid in the Late Silurian resembles the reappearance of other “Lazarus taxa” that were thought to have been eliminated during mass extinction events. The naraoiid lineage survived the Late Ordovician biotic crisis, but in this case the “Lazarus effect” seems likely to be taphonomic in origin.

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Yohoia Walcott and Plenocaris N. Gen., arthropods from the Burgess Shale, Middle Cambrian, British Columbia

10.4095/103458 ◽

1974 ◽

Cited By ~ 3

Author(s):

H B Whittington

Keyword(s):

British Columbia ◽

Burgess Shale ◽

Middle Cambrian

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Chance, Evolution, and the Metaphysical Implications of Paleontological Practice

10.1007/978-3-030-75797-7_7 ◽

2021 ◽

pp. 119-143

Author(s):

Alan C. Love

Keyword(s):

Evolutionary Process ◽

Cambrian Explosion ◽

Burgess Shale ◽

Stephen Jay Gould ◽

History Of

AbstractFor several decades, a debate has been waged over how to interpret the significance of fossils from the Burgess Shale and Cambrian Explosion. Stephen Jay Gould argued that if the “tape of life” was rerun, then the resulting lineages would differ radically from what we find today, implying that humans are a happy accident of evolution. Simon Conway Morris argued that if the “tape of life” was rerun, the resulting lineages would be similar to what we now observe, implying that intelligence would still emerge from an evolutionary process. Recent methodological innovations in paleontological practice call into question both positions and suggest that global claims about the history of life, whether in terms of essential contingency or predictable convergence, are unwarranted.

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A review of dinosaurian body fossils from British Columbia, Canada

10.7287/peerj.preprints.1369v2 ◽

2015 ◽

Author(s):

Iain J Reid

Keyword(s):

United States ◽

British Columbia ◽

Western United States ◽

Burgess Shale ◽

History Of ◽

Prairie Provinces

Since the 1900s, dinosaur fossils have been discovered from Jurassic to Cretaceous age strata, from all across the prairie provinces of Canada and the Western United States, yet little material is known from the outer provinces and territories. In British Columbia, fossils have long been uncovered from the prevalent mid-Cambrian Burgess Shale, but few deposits date from the Mesozoic, and few of these are dinosaurian. The purpose of this paper is to review the history of dinosaurian body fossils in British Columbia. The following dinosaurian groups are represented: coelurosaurians, thescelosaurids, iguanodontians, ankylosaurs and hadrosaurs.

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Waptia fieldensis Walcott, a mandibulate arthropod from the middle Cambrian Burgess Shale

Royal Society Open Science ◽

10.1098/rsos.172206 ◽

2018 ◽

Vol 5 (6) ◽

pp. 172206 ◽

Cited By ~ 19

Author(s):

Jean Vannier ◽

Cédric Aria ◽

Rod S. Taylor ◽

Jean-Bernard Caron

Keyword(s):

Evolutionary History ◽

The Body ◽

Formal Description ◽

Front Part ◽

Burgess Shale ◽

Middle Cambrian ◽

History Of ◽

Ellipsoid Bodies ◽

Active Swimming ◽

Prey Items

Waptia fieldensis Walcott, 1912 is one of the iconic animals from the middle Cambrian Burgess Shale biota that had lacked a formal description since its discovery at the beginning of the twentieth century. This study, based on over 1800 specimens, finds that W. fieldensis shares general characteristics with pancrustaceans, as previous authors had suggested based mostly on its overall aspect. The cephalothorax is covered by a flexible, bivalved carapace and houses a pair of long multisegmented antennules, palp-bearing mandibles, maxillules, and four pairs of appendages with five-segmented endopods—the anterior three pairs with long and robust enditic basipods, the fourth pair with proximal annulations and lamellae. The post-cephalothorax has six pairs of lamellate and fully annulated appendages which appear to be extensively modified basipods rather than exopods. The front part of the body bears a pair of stalked eyes with the first ommatidia preserved in a Burgess Shale arthropod, and a median ‘labral’ complex flanked by lobate projections with possible affinities to hemi-ellipsoid bodies. Waptia confirms the mandibulate affinity of hymenocarines, retrieved here as part of an expanded Pancrustacea, thereby providing a novel perspective on the evolutionary history of this hyperdiverse group. We construe that Waptia was an active swimming predator of soft prey items, using its anterior appendages for food capture and manipulation, and also potentially for clinging to epibenthic substrates.

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