Paleozoology

@book{olson1971vertebrate2,
    author = "Olson, E. C",
    title = "Vertebrate Paleozoology",
    year = "1971",
    publisher = "New York, Wiley-Interscience, 839 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Olson, E. C., 1971, Vertebrate Paleozoology: New York, Wiley-Interscience, 839 p.}"
}

@article{piper1972sediments,
    author = "Piper, David J. W.",
    title = "Sediments of the Middle Cambrian Burgess Shale, Canada",
    year = "1972",
    journal = "Lethaia",
    url = "https://doi.org/10.1111/j.1502-3931.1972.tb00850.x",
    doi = "10.1111/j.1502-3931.1972.tb00850.x",
    number = "2",
    pages = "169-175",
    volume = "5"
}

A study of new specimens of the bivalved arthropod Protocaris preriosa Resser, 1929 from the Burgess Shale has added much information to the original description, and the species is removed to a new genus Bra11c/1iocaris. Prorocaris marshi Walcott, 1884 and Dioxycaris arge11ra (Walcott, 1886) are also redescribed to facilitate comparison. The cephalic region of Bra11chiocaris preriosa bore a paired antenna anterior to a pair of stout appendages which may have been chelate. Suboval valves, the dorsal margin terminating anteriorly and posteriorly in a small pointed process, covered the anterior of the body. The trunk included about 46 divisions followed by a telson bearing a pair of short pointed processes. The lamellate trunk appendages may have been biramous, with a short, segmented proximal element. The animal probably swam near the seabed by metachronal movements of the lamellate appendages, which may also have functioned in respiration. B. pretiosa shows closest affinities to the branchiopod Crustacea among extant arthropods but is considered unlikely to represent a direct evolutionary predecessor of this group. The trunk of Protocaris marshi included about 65 divisions; the tel son processes were elongate and curved. The appendages are unknown. The carapace of Dioxycaris arge11ta is similar in outline and size to that of Branchiocaris preliosa but the only known specimen is poorly preserved and lacks evidence of the soft-part morphology.

@misc{briggs1976the,
    author = "Briggs, D E G",
    title = "The Arthropod Branchiocaris N. Gen., Middle Cambrian, Burgess Shale, British Columbia",
    year = "1976",
    abstract = "A study of new specimens of the bivalved arthropod Protocaris preriosa Resser, 1929 from the Burgess Shale has added much information to the original description, and the species is removed to a new genus Bra11c/1iocaris. Prorocaris marshi Walcott, 1884 and Dioxycaris arge11ra (Walcott, 1886) are also redescribed to facilitate comparison. The cephalic region of Bra11chiocaris preriosa bore a paired antenna anterior to a pair of stout appendages which may have been chelate. Suboval valves, the dorsal margin terminating anteriorly and posteriorly in a small pointed process, covered the anterior of the body. The trunk included about 46 divisions followed by a telson bearing a pair of short pointed processes. The lamellate trunk appendages may have been biramous, with a short, segmented proximal element. The animal probably swam near the seabed by metachronal movements of the lamellate appendages, which may also have functioned in respiration. B. pretiosa shows closest affinities to the branchiopod Crustacea among extant arthropods but is considered unlikely to represent a direct evolutionary predecessor of this group. The trunk of Protocaris marshi included about 65 divisions; the tel son processes were elongate and curved. The appendages are unknown. The carapace of Dioxycaris arge11ta is similar in outline and size to that of Branchiocaris preliosa but the only known specimen is poorly preserved and lacks evidence of the soft-part morphology.",
    url = "https://doi.org/10.4095/103962",
    doi = "10.4095/103962"
}

The Burgess Shale (Middle Cambrian) polychaetes Canadia spinosa Walcott, Burgessochaeta setigera (Walcott) gen. nov. and Peronochaeta dubia (Walcott) gen. nov. are redescribed on the basis of Walcott’s type specimens and on much additional material. Two new polychaetes Insolicorypha psygma gen. et sp. nov. and Stephenoscolex argutus gen. et sp. nov. are described. A poorly preserved specimen of unknown generic affinity is described as type A. The polychaetes are preserved as thin films that adhere to both sides of the split in the rock so that part and counterpart may be available. In C. spinosa, B. setigera and I. psygma, parts of the bodies such as the fascicles of setae are separated by thin layers of sediment that apparently seeped in during turbulent transport in turbidites or mudflows. The bodies therefore lie on two or more planes of microbedding and the factors that control exposure across a specimen are discussed. Aspects of the palaeoecology of the Burgess Shale are reviewed, including the distance the biota was transported prior to burial, the reasons for the exquisite preservation, and the effects of sedimentary compaction. C. spinosa was characterized by broad notosetae that extended across the dorsum, and large fascicles of neurosetae. Lobate branchiae were situated in the inter-ramal spaces. The prostomium bore a pair of elongate tentacles and the straight gut had an eversible unarmed proboscis. Several lines of evidence suggest that C. spinosa was an active benthonic swimmer. B. setigera was peculiar in possessing identical notosetae and neurosetae along the entire body. Long anterior tentacles, possibly of peristomial origin, may have been used in feeding. Indirect evidence indicates that B. setigera inhabited a burrow which it might have excavated with its proboscis. P. dubia may also have burrowed but it had uniramous parapodia bearing simple and acicular setae. The prostomium bore a pair of short appendages. I. psygma had extended neuropodia bearing cirri and elongate setae. The notopodia were reduced and cirri appear to have been wanting. The peculiar prostomium carried a pair of appendages. I. psygma is regarded as a pelagic polychaete. S. argutus possessed uniramous parapodia with simple stout setae. The bilobed prostomium bore at least one pair, and perhaps three pairs, of short appendages. Type A was the largest of the Burgess Shale polychaetes and had prominent setae on at least the anterior section of the body. Type A was a sediment eater but the feeding habits of the other polychaetes are uncertain. Particular attention is given to the influence of decay on the Burgess Shale polychaetes. To place the Burgess Shale polychaetes in some geological perspective other Cambrian worms, including a polychaete from the Spence Shale of Utah, are briefly redescribed and the late Precambrian (Ediacarian) worms Dickinsonia, Spriggina and Marywadea are assessed. Contrary to the findings of other workers, no convincing evidence for placing these latter worms in the polychaetes is forthcoming.

@article{conwaymorris1979middle,
    author = "Conway Morris, Simon",
    title = "Middle Cambrian polychaetes from the Burgess Shale of British Columbia",
    year = "1979",
    journal = "Philosophical Transactions of the Royal Society of London. B, Biological Sciences",
    abstract = "The Burgess Shale (Middle Cambrian) polychaetes Canadia spinosa Walcott, Burgessochaeta setigera (Walcott) gen. nov. and Peronochaeta dubia (Walcott) gen. nov. are redescribed on the basis of Walcott’s type specimens and on much additional material. Two new polychaetes Insolicorypha psygma gen. et sp. nov. and Stephenoscolex argutus gen. et sp. nov. are described. A poorly preserved specimen of unknown generic affinity is described as type A. The polychaetes are preserved as thin films that adhere to both sides of the split in the rock so that part and counterpart may be available. In C. spinosa, B. setigera and I. psygma, parts of the bodies such as the fascicles of setae are separated by thin layers of sediment that apparently seeped in during turbulent transport in turbidites or mudflows. The bodies therefore lie on two or more planes of microbedding and the factors that control exposure across a specimen are discussed. Aspects of the palaeoecology of the Burgess Shale are reviewed, including the distance the biota was transported prior to burial, the reasons for the exquisite preservation, and the effects of sedimentary compaction. C. spinosa was characterized by broad notosetae that extended across the dorsum, and large fascicles of neurosetae. Lobate branchiae were situated in the inter-ramal spaces. The prostomium bore a pair of elongate tentacles and the straight gut had an eversible unarmed proboscis. Several lines of evidence suggest that C. spinosa was an active benthonic swimmer. B. setigera was peculiar in possessing identical notosetae and neurosetae along the entire body. Long anterior tentacles, possibly of peristomial origin, may have been used in feeding. Indirect evidence indicates that B. setigera inhabited a burrow which it might have excavated with its proboscis. P. dubia may also have burrowed but it had uniramous parapodia bearing simple and acicular setae. The prostomium bore a pair of short appendages. I. psygma had extended neuropodia bearing cirri and elongate setae. The notopodia were reduced and cirri appear to have been wanting. The peculiar prostomium carried a pair of appendages. I. psygma is regarded as a pelagic polychaete. S. argutus possessed uniramous parapodia with simple stout setae. The bilobed prostomium bore at least one pair, and perhaps three pairs, of short appendages. Type A was the largest of the Burgess Shale polychaetes and had prominent setae on at least the anterior section of the body. Type A was a sediment eater but the feeding habits of the other polychaetes are uncertain. Particular attention is given to the influence of decay on the Burgess Shale polychaetes. To place the Burgess Shale polychaetes in some geological perspective other Cambrian worms, including a polychaete from the Spence Shale of Utah, are briefly redescribed and the late Precambrian (Ediacarian) worms Dickinsonia, Spriggina and Marywadea are assessed. Contrary to the findings of other workers, no convincing evidence for placing these latter worms in the polychaetes is forthcoming.",
    url = "https://doi.org/10.1098/rstb.1979.0006",
    doi = "10.1098/rstb.1979.0006",
    number = "1007",
    pages = "227-274",
    volume = "285"
}

@article{morris1979the,
    author = "Morris, Simon Conway",
    title = "The Burgess Shale (Middle Cambrian) Fauna",
    year = "1979",
    journal = "Annual Review of Ecology and Systematics",
    url = "https://doi.org/10.1146/annurev.es.10.110179.001551",
    doi = "10.1146/annurev.es.10.110179.001551",
    number = "1",
    pages = "327-349",
    volume = "10"
}

Six species of arthropods from the Walcott Collection, U.S. National Museum, are described. Molaria spinifera Walcott is known from over 100 specimens, a sample that reveals the morphology fairly fully. Between one and 12 specimens of the other species are known, and yield limited information. M. spinifera had a smooth, convex exoskeleton, not trilobed, the cephalic shield being a quarter-sphere in shape, eight trunk tergites diminishing in size posteriorly and the cylindrical telson having a short ventral spine and a long, jointed posterior spine. The cephalon bore a pair of short, slim antennae and three pairs of biramous appendages. There were eight pairs of similar biramous appendages on the trunk. The biramous appendage had a large basal podomere, a segmented inner walking branch, and a lobate outer branch arising from the basal podomere and bearing marginal lamellae. The sagittal length of cephalon, trunk and telson ranged from 8 to 26 mm, the posterior spine slightly exceeding this length; the smallest specimens are similar to the largest. The animal lacked eyes, and was probably benthic and may have been a scavenger and deposit feeder. Habelia optata Walcott was superficially similar to M. spinfera, the trunk being of 12 tergites; there was no cylindrical telson, but a ridged and barbed spine inserted into the 12th tergite, the spine having a joint at about two-thirds its length. The external surface of the exoskeleton was tuberculate; the pleurae of the tergites curved back increasingly strongly posteriorly, the tips being spinose. The cephalon appears to have borne a slim, short pair of antennae and two pairs of biramous appendages; the proximal portions of the jointed inner branches may have been adapted for grinding food. The first six trunk somites bore biramous limbs, the inner branch being a relatively long walking leg, the outer a lobe having marginal lamellae; on the posterior trunk somites there is no trace of the inner branch, but the outer was present. H. optata lacked eyes and was probably a benthic animal. Only the smooth exoskeleton of a possible second species, H? brevicauda Simonetta, is known, of which the posterior spine is short and bluntly rounded. The new genus and species Sarotrocercus oblita is erected for a few specimens, in which the body is about 1 cm in length, and behind which is a slim spine having a group of spines at the tip. From beneath the anterolateral margin of the cephalic shield a large eye projected, and the cephalon bore also one pair of large, jointed appendages. Behind these were pairs of lobed appendages bearing marginal lamellae, one on the cephalon and one on each of the nine trunk somites. This small species may have drifted and swum in the higher water layers, the occasional carcass lying on the sea bottom having been preserved. The single specimen of Actaeus armatus Simonetta is over 6 cm in length. The exoskeleton of this specimen is divided into cephalic shield with marginal eye lobe, 11 trunk tergites and a triangular terminal plate. The anterior cephalic appendage was Leanchoil-like, the stout proximal portion being curved and ending in a group of claws, the next two podomeres bearing long, slim extensions. The head shield also bore three pairs of biramous appendages, consisting of a small jointed inner branch and a large lobed outer branch with marginal lamellae; appendages like these outer branches are preserved beneath the trunk tergites. Only two specimens are identified as Alalcomenaeus cambricus Simonetta (length 3-4 cm). The exoskeleton is divisible into cephalic shield, trunk of probably 12 tergites, and an ovate terminal plate which has lateral bands. The cephalon has a marginal eye lobe and an anterior appendage which is broad proximally, the long distal portion being slim. The holotype shows a series of lobed appendages, the first three cephalic. Between them project the curved, pointed terminations of inner branches. The second specimen suggests that these lobed appendages bore marginal filaments, and reveals the inner branches as blade-shaped, and spinose on the inward-facing margin. These biramous appendages were present on all the trunk somites, being largest anteriorly. These remarkable appendages suggest a benthic scavenger, able to hold on to, and tear up, a carcass. ‘ Leanchoilia protogonia ’ Simonetta is most probably a composite, a poorly preserved Leanchoilia superlata lying on an unidentified, branching organism. The five species showing appendages extend greatly the known range of variation in morphology of the Burgess Shale arthropods. Affinities are discussed, but familial and higher classification is postponed, pending completion of work on all the arthropods from the shale.

@article{whittington1981rare,
    author = "Whittington, Harry Blackmore",
    title = "Rare arthropods from the Burgess Shale, Middle Cambrian, British Columbia",
    year = "1981",
    journal = "Philosophical Transactions of the Royal Society of London. B, Biological Sciences",
    abstract = "Six species of arthropods from the Walcott Collection, U.S. National Museum, are described. Molaria spinifera Walcott is known from over 100 specimens, a sample that reveals the morphology fairly fully. Between one and 12 specimens of the other species are known, and yield limited information. M. spinifera had a smooth, convex exoskeleton, not trilobed, the cephalic shield being a quarter-sphere in shape, eight trunk tergites diminishing in size posteriorly and the cylindrical telson having a short ventral spine and a long, jointed posterior spine. The cephalon bore a pair of short, slim antennae and three pairs of biramous appendages. There were eight pairs of similar biramous appendages on the trunk. The biramous appendage had a large basal podomere, a segmented inner walking branch, and a lobate outer branch arising from the basal podomere and bearing marginal lamellae. The sagittal length of cephalon, trunk and telson ranged from 8 to 26 mm, the posterior spine slightly exceeding this length; the smallest specimens are similar to the largest. The animal lacked eyes, and was probably benthic and may have been a scavenger and deposit feeder. Habelia optata Walcott was superficially similar to M. spinfera, the trunk being of 12 tergites; there was no cylindrical telson, but a ridged and barbed spine inserted into the 12th tergite, the spine having a joint at about two-thirds its length. The external surface of the exoskeleton was tuberculate; the pleurae of the tergites curved back increasingly strongly posteriorly, the tips being spinose. The cephalon appears to have borne a slim, short pair of antennae and two pairs of biramous appendages; the proximal portions of the jointed inner branches may have been adapted for grinding food. The first six trunk somites bore biramous limbs, the inner branch being a relatively long walking leg, the outer a lobe having marginal lamellae; on the posterior trunk somites there is no trace of the inner branch, but the outer was present. H. optata lacked eyes and was probably a benthic animal. Only the smooth exoskeleton of a possible second species, H? brevicauda Simonetta, is known, of which the posterior spine is short and bluntly rounded. The new genus and species Sarotrocercus oblita is erected for a few specimens, in which the body is about 1 cm in length, and behind which is a slim spine having a group of spines at the tip. From beneath the anterolateral margin of the cephalic shield a large eye projected, and the cephalon bore also one pair of large, jointed appendages. Behind these were pairs of lobed appendages bearing marginal lamellae, one on the cephalon and one on each of the nine trunk somites. This small species may have drifted and swum in the higher water layers, the occasional carcass lying on the sea bottom having been preserved. The single specimen of Actaeus armatus Simonetta is over 6 cm in length. The exoskeleton of this specimen is divided into cephalic shield with marginal eye lobe, 11 trunk tergites and a triangular terminal plate. The anterior cephalic appendage was Leanchoil-like, the stout proximal portion being curved and ending in a group of claws, the next two podomeres bearing long, slim extensions. The head shield also bore three pairs of biramous appendages, consisting of a small jointed inner branch and a large lobed outer branch with marginal lamellae; appendages like these outer branches are preserved beneath the trunk tergites. Only two specimens are identified as Alalcomenaeus cambricus Simonetta (length 3-4 cm). The exoskeleton is divisible into cephalic shield, trunk of probably 12 tergites, and an ovate terminal plate which has lateral bands. The cephalon has a marginal eye lobe and an anterior appendage which is broad proximally, the long distal portion being slim. The holotype shows a series of lobed appendages, the first three cephalic. Between them project the curved, pointed terminations of inner branches. The second specimen suggests that these lobed appendages bore marginal filaments, and reveals the inner branches as blade-shaped, and spinose on the inward-facing margin. These biramous appendages were present on all the trunk somites, being largest anteriorly. These remarkable appendages suggest a benthic scavenger, able to hold on to, and tear up, a carcass. ‘ Leanchoilia protogonia ’ Simonetta is most probably a composite, a poorly preserved Leanchoilia superlata lying on an unidentified, branching organism. The five species showing appendages extend greatly the known range of variation in morphology of the Burgess Shale arthropods. Affinities are discussed, but familial and higher classification is postponed, pending completion of work on all the arthropods from the shale.",
    url = "https://doi.org/10.1098/rstb.1981.0033",
    doi = "10.1098/rstb.1981.0033",
    number = "1060",
    pages = "329-357",
    volume = "292"
}

Soft-bodied and lightly sclerotized Burgess shale fossils have been found at more than a dozen new localities in an area extending for 20 kilometers along the front of the Cathedral Escarpment in the Middle Cambrian Stephen Formation of the Canadian Rockies. Five different fossil assemblages from four stratigraphic levels have been recognized. These assemblages represent distinct penecontemporaneous marine communities that together make up a normal fore-reef faunal complex.

@article{collins1983new,
    author = "Collins, Desmond and Briggs, Derek and Morris, Simon Conway",
    title = "New Burgess Shale Fossil Sites Reveal Middle Cambrian Faunal Complex",
    year = "1983",
    journal = "Science",
    abstract = "Soft-bodied and lightly sclerotized Burgess shale fossils have been found at more than a dozen new localities in an area extending for 20 kilometers along the front of the Cathedral Escarpment in the Middle Cambrian Stephen Formation of the Canadian Rockies. Five different fossil assemblages from four stratigraphic levels have been recognized. These assemblages represent distinct penecontemporaneous marine communities that together make up a normal fore-reef faunal complex.",
    url = "https://doi.org/10.1126/science.222.4620.163",
    doi = "10.1126/science.222.4620.163",
    number = "4620",
    pages = "163-167",
    volume = "222"
}

@misc{conwaymorris1986the1,
    author = "Conway Morris, S",
    title = "The community structure of the Middle Cambrian phyllopod bed (Burgess Shale)",
    year = "1986",
    howpublished = "Palaeontology, v. 29, p. 423-467",
    note = "talkorigins\_source = {true}; raw\_reference = {Conway Morris, S., 1986, The community structure of the Middle Cambrian phyllopod bed (Burgess Shale): Palaeontology, v. 29, p. 423-467.}"
}

@inproceedings{awaji1999the,
    author = "Awaji, Tetsuhiko",
    title = "The Cambrian Burgess shale creatures",
    year = "1999",
    booktitle = "ACM SIGGRAPH 99 Electronic art and animation catalog",
    url = "https://doi.org/10.1145/312379.312873",
    doi = "10.1145/312379.312873",
    pages = "119"
}

@article{caron2006taphonomy,
    author = "CARON, J.-B. and JACKSON, D. A.",
    title = "TAPHONOMY OF THE GREATER PHYLLOPOD BED COMMUNITY, BURGESS SHALE",
    year = "2006",
    journal = "PALAIOS",
    url = "https://doi.org/10.2110/palo.2003.p05-070r",
    doi = "10.2110/palo.2003.p05-070r",
    number = "5",
    pages = "451-465",
    volume = "21"
}

@article{caron2008paleoecology,
    author = "Caron, Jean-Bernard and Jackson, Donald A.",
    title = "Paleoecology of the Greater Phyllopod Bed community, Burgess Shale",
    year = "2008",
    journal = "Palaeogeography, Palaeoclimatology, Palaeoecology",
    url = "https://doi.org/10.1016/j.palaeo.2007.05.023",
    doi = "10.1016/j.palaeo.2007.05.023",
    number = "3",
    pages = "222-256",
    volume = "258"
}

We provide the most detailed sedimentological log to date through the Phyllopod Bed of the mid-Cambrian Burgess Shale Formation of British Columbia, based on millimetre-scale logging of a suite of thin sections. The sedimentary facies is dominated by alternations of homogeneous mudstone and a coarser-grained, laminated, variably sandy and shelly mudstone that is locally micronodular. Most boundaries between these two lithologies are gradational, and discrete fining-upwards turbidite units were rarely recognized. Such a pattern is interpreted to indicate rapid sedimentation of up to decimetre-thick units at this location from pulsatory, quasi-continuous density currents consistent with earlier proposals of exceptional preservation through rapid burial; the density currents responsible were probably largely akin to mud-rich slurries, helping explain the transport and entombment of the fossils. The homogeneous mudstone units are characterized by numerous distinctive lenses of pyrite framboids or subeuhedral crystals, previously interpreted as small ripples. Their 3D shape, however, suggests an origin as subspherical early diagenetic aggregates; their present morphology is consistent with the high levels of compaction inferred from the preservation of fossils.

@article{gabbott2008sedimentation,
    author = "Gabbott, S.E. and Zalasiewicz, J. and Collins, D.",
    title = "Sedimentation of the Phyllopod Bed within the Cambrian Burgess Shale Formation of British Columbia",
    year = "2008",
    journal = "Journal of the Geological Society",
    abstract = "We provide the most detailed sedimentological log to date through the Phyllopod Bed of the mid-Cambrian Burgess Shale Formation of British Columbia, based on millimetre-scale logging of a suite of thin sections. The sedimentary facies is dominated by alternations of homogeneous mudstone and a coarser-grained, laminated, variably sandy and shelly mudstone that is locally micronodular. Most boundaries between these two lithologies are gradational, and discrete fining-upwards turbidite units were rarely recognized. Such a pattern is interpreted to indicate rapid sedimentation of up to decimetre-thick units at this location from pulsatory, quasi-continuous density currents consistent with earlier proposals of exceptional preservation through rapid burial; the density currents responsible were probably largely akin to mud-rich slurries, helping explain the transport and entombment of the fossils. The homogeneous mudstone units are characterized by numerous distinctive lenses of pyrite framboids or subeuhedral crystals, previously interpreted as small ripples. Their 3D shape, however, suggests an origin as subspherical early diagenetic aggregates; their present morphology is consistent with the high levels of compaction inferred from the preservation of fossils.",
    url = "https://doi.org/10.1144/0016-76492007-023",
    doi = "10.1144/0016-76492007-023",
    number = "1",
    pages = "307-318",
    volume = "165"
}