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211.
Siversson, M., Cook, T.D., Ryan, H.E., Watkins, D.K., Tatarnic, N.J., Downes, P.J. & Newbrey, M.G. May 2018. Anacoracid sharks and calcareous nannofossil stratigraphy of the mid-Cretaceous Gearle Siltstone and Haycock Marl in the lower Murchison River area, Western Australia. Alcheringa XX, XX–XX.

Extensive bulk sampling over the past 20 years and greatly improved stratigraphic control permitted a meaningful revision of previously described anacoracid sharks from the ‘upper’ Gearle Siltstone and lower Haycock Marl in the lower Murchison River area, Western Australia. Isolated teeth of anacoracids are rare in the lower three (Beds 1–3) of four stratigraphic units of the ‘upper’ Gearle Siltstone but relatively common in the uppermost layer (Bed 4) and in the lower part of the overlying Haycock Marl. On the basis of calcareous nannofossils, Beds 1 and 2 of the ‘upper’ Gearle Siltstone can be placed in the uppermost upper Albian calcareous nannofossil Subzone CC9b whereas Bed 3 can be referred to the lowermost Cenomanian CC9c Subzone. Bed 1 yielded fragments of strongly serrated anacoracid teeth as well as a single, smooth-edged tooth. The samples from Beds 2 and 3 contained a few small fragments of serrated anacoracid teeth. Bed 4 is barren of calcareous nannofossils but the presence of a dentally advanced tooth of the cosmopolitan lamniform genus Cretoxyrhina in combination with the age of the overlying Haycock Marl indicate deposition within the younger half of the Cenomanian. The unit produced teeth of two anacoracids; Squalicorax acutus sp. nov. and S. bazzii sp. nov. The basal, laminated part of the Haycock Marl is placed in the uppermost upper Cenomanian part of CC10b. It yielded Squalicorax mutabilis sp. nov. and S. aff. S. bernardezi. Exceptionally well-preserved teeth of the former species span a 5:1 size ratio range for teeth of comparable jaw position. The teeth reveal strong ontogenetic heterodonty with a large increase in the relative size of the main cusp with age and the transition from a vertical distal heel of the crown in very young juveniles to a sub-horizontal, well demarcated heel in ‘adult’ teeth. An isolated phosphatic lens in the lower part of the Haycock Marl produced calcareous nannofossils indicative of the CC10b SubZone, most likely the lowermost lower Turonian part. It contains teeth of Squalicorax mutabilis sp. nov., S. aff. S. bernardezi, and S. sp. C.

Mikael Siversson* [], Helen E. Ryan [] and Peter Downes [] Department of Earth and Planetary Sciences, Western Australian Museum, 49 Kew Street, Welshpool, Western Australia 6106, Australia; David K. Watkins [] Department of Earth and Atmospheric Sciences, University of Nebraska, Lincoln, NE 68588, USA; Todd D. Cook [] School of Science, Penn State Behrend, 4205 College Drive, Erie, PA 16563, USA; Nikolai J. Tatarnic? [] Department of Terrestrial Zoology, Western Australian Museum, 49 Kew Street, Welshpool, Western Australia 6106, Australia; Michael G. Newbrey? [] Department of Biology, Columbus State University, Columbus, GA 31907-5645, USA. *Also affiliated with: School of Molecular and Life Sciences, Curtin University, Kent Street, Bentley, WA 6102, Australia. ?Also affiliated with: Centre for Evolutionary Biology, University of Western Australia, Crawley, Western Australia 6009. ?Also affiliated with: Canadian Fossil Discovery Centre, 111-B Gilmour Street, Morden, Manitoba R6 M 1N9, Canada.

http://zoobank.org/urn:lsid:zoobank.org:pub:97D5131F-C0D5-4A7E-9C9A-0FDF13BFCBBB

http://zoobank.org/urn:lsid:zoobank.org:act:5977DCC2-355C-4732-8B0A-4BD0EABBA8DE

http://zoobank.org/urn:lsid:zoobank.org:act:2D7C4147-B756-4434-847A-B0C1C6D167DF

http://zoobank.org/urn:lsid:zoobank.org:act:33F3B55E-41E0-45B3-8296-A3B95C17B41D  相似文献   

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Tim Cook 《War & society》2020,39(3):221-226
In early 1942, 23,000 Japanese Canadians on the West Coast were forcibly relocated against their will to the interior of Canada after Japan entered the war against the Allies. This forced relocation left deep scars in that community. Decades later, Japanese Canadians mounted a redress campaign for an official apology and financial restitution. This provocation examines that campaign and explores how it has shaped Canada’s constructed memory of the Second World War.  相似文献   
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Fine, polished abrasion of teeth provides evidence for use of traditional oral hygiene practices in 32 fragmentary dentitions from a cemetery for newly arrived enslaved Africans who died before leaving Valongo, the slave port and market of Rio de Janeiro. We infer that chewing sticks were used before these people were enslaved. Cosmetic dental modification and abrasion of tooth roots occur in some individuals. High caries frequency, tooth loss and hypercementosis characteristic remains of enslaved Africans with longer residence in the New World were not found in this unique collection. We review evidence that the practice of using chewing sticks persists in some regions of the Americas. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Taking as my example, the memories of Duna people at Lake Kopiago, who inhabit the northwestern part of the Southern Highlands Province of Papua New Guinea, I illustrate some of the ways events, and memories of them, have been constructed, manipulated and recast over the last twenty five years. By paying particular attention to a well known originary narrative, I show that space, the revelation of new knowledge via a spirit medium and the reinterpretation and negotiation of the meanings attached to events can result in the production of new memories about the past and the future.  相似文献   
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Using Inuit as an illustration, this article discusses what it means to live in community, and argues that by taking people's moral geographies into account one may understand more fully the make‐up of community. The article maintains that their moral geography creates a feeling among Inuit of obligation for the other. It is this obligation that serves as the basis for community. The article theorizes about the implications of internalized mores based on obligation, and discusses how, in contrast to the concept of rights, such mores contribute to the formation and maintenance of community. The article concludes that developing a situated understanding of people's moral geographies may help to expand our comprehension of community construction and maintenance.  相似文献   
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