Anacoracid sharks and calcareous nannofossil stratigraphy of the mid-Cretaceous ‘upper’ Gearle Siltstone and Haycock Marl in the lower Murchison River area,Western Australia

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* [mikael.siversson@museum.wa.gov.au], Helen E. Ryan [helen.ryan@museum.wa.gov.au] and Peter Downes [peter.downes@museum.wa.gov.au] Department of Earth and Planetary Sciences, Western Australian Museum, 49 Kew Street, Welshpool, Western Australia 6106, Australia; David K. Watkins [dwatkins@unl.edu] Department of Earth and Atmospheric Sciences, University of Nebraska, Lincoln, NE 68588, USA; Todd D. Cook [tdc15@psu.edu] School of Science, Penn State Behrend, 4205 College Drive, Erie, PA 16563, USA; Nikolai J. Tatarnic? [nikolai.tatarnic@museum.wa.gov.au] Department of Terrestrial Zoology, Western Australian Museum, 49 Kew Street, Welshpool, Western Australia 6106, Australia; Michael G. Newbrey? [newbrey_michael@columbusstate.edu] 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     

LONE WOLVES? ISOLATION AND SOLITUDE WITHIN THE FRONTIER TRAVEL EXPERIENCE

The frontier traveller, venturing out into the peripheral parts of our world such as the poles, the peaks of mountains or the great deserts, must deal with the remoteness and riskiness of the setting. The traveller is mentally apart from friends and family, and immediate rescue may be difficult, if not impossible. This article explores the attraction of remoteness, isolation and solitude for the frontier traveller, using qualitative interview and biographical data collected in a study of frontier travel experiences. Some participants referred to intense, spiritual experiences at the frontier, with the remoteness and silence of their journeys facilitating reflection, both internal and external. Isolation and solitude appear to engender a sense of freedom and escape from the cares of everyday life in the frontier traveller, while the study also highlights the attraction of self‐sufficiency in remote settings, particularly during the solo frontier travel experience, where the individual is forced to make decisions and manage situations, without recourse to another's advice, skills or experience. The resultant heightened challenge and risk was perceived as a form of authenticity by some participants. The links between isolation and opportunities for self‐actualization are also noted in this article. The implications of these findings for marketing tourism experiences are examined, given the potential for the peripheries to become more accessible to tourists in the future, as well as the role played by culture and privilege in these types of adventurous experiences in far‐flung locations.     

Strangers and estrangement: young people’s renegotiations of birth and foster family relationships as they transition out of care and the implications for the state as parent*

ABSTRACT

Many young people ageing out of state care continue to experience very poor life outcomes. Based on research following 21 care leavers aged 15–18 over three years, this article charts how children’s experiences in troubled birth families are often compounded in care by multiple placement moves, the gradual disintegration of sibling units over time and troubling relationships with the adults charged with their care. It considers the effects of living with strangers and of transient relationships with carers and professionals, and explores young people’s feelings of rejection by, and responsibility for, their birth families. The capacity of the ‘corporate parent’ model to ensure adequate attention is paid to relationships in young people’s lives is questioned. Hollingsworth’s theory of foundational rights, incorporating considerations of relational autonomy, is utilised to reconsider the state’s obligations towards children for whom it has taken on the parental role, both during and beyond their legal minority.