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Parmar, V., Magotra, R., Norboo, R. & Prasad, G.V.R., July 2016. Rodent-based age appraisal of the Lower Siwalik Subgroup of Kalaunta, Ramnagar, Jammu, India. Alcheringa 41, xx-xx. ISSN 0311-5518.

Rocks of the Lower Siwalik Subgroup exposed around Ramnagar town in Jammu, India, have been known for more than 90 years to yield Chinji-equivalent (14.2–11.2 Ma) hominoid fossils. In 1997, the fossil ape Sivapithecus reported near Kalaunta village in the vicinity of Ramnagar was argued to be about 18 Ma old by its discoverers. This had implications for hominoid evolutionary studies, as molecular clock calibrations are commonly based on Sivapithecus first appearance datum (FAD). In a paper published in 2010, the identification of this hominoid tooth was questioned and reassigned to a suid. Recently, based upon the discovery of an indeterminate fossil bovid from the supposedly hominoid-yielding site near Kalaunta, an age estimate between ca 13.9 and 10.8 Ma was provided. As rodent biochronology has proven to be useful in age assignment of upper Cenozoic terrestrial sequences, the age of the fossil-bearing Lower Siwalik Subgroup of Kalaunta is re-assessed based upon newly recovered cricetid taxa. The cricetid rodents from this site comprise Punjabemys downsi and P. mikros. These two species are known to exist in the well-dated Potwar Siwalik Group succession between 14.3 and 12.6 Ma and between 16.3 and 13.0 Ma, respectively. Based on the overlapping temporal ranges of the cricetid taxa and an indeterminate Bovidae (ca 13.9–10.8 Ma) reported previously from this area, an age of 13.9–13.0 Ma is inferred for rocks occurring in the vicinity of Kalaunta. The new finds refute earlier claims of rocks in the area extending back to ca 18 Ma or as young as 10.8 Ma.

Varun Parmar [], Rahul Magotra [] and Rigzin Norboo [], Post Graduate Department of Geology, University of Jammu, Jammu, 180 006, India; Guntupalli Veera Raghavendra Prasad [], Department of Geology, Centre for Advanced Studies, University of Delhi, Delhi, 110 007, India.  相似文献   

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Apical periodontal cysts are benign lesions developing in relation to the apices of non‐vital teeth due to inflammatory response from the infective pulp. These are epithelium‐lined bony cavities containing fluid. Despite being widely reported in medical/dental literature, this common condition is poorly diagnosed and documented in the archaeological literature. We aim to clarify the correct terminology, demonstrate bony manifestations at different stages of pathogenesis of chronic periapical dental lesions into granuloma and apical periodontal cysts, and to describe diagnostic criteria which would provide practical guidelines for the diagnosis of these conditions. Three identified skulls from the International Exchange Collection, housed in the Anthropological Museum at the University of Coimbra, are used to identify the progression of this condition from a small periapical granuloma to a large apical periodontal cyst with expansion of alveolar and facial bones. The pathogenesis of this condition is described, together with its surgical management in the early 20th century in Portugal, which is the period in which these individuals lived. Confusion resulting from the different terminologies can be avoided if the term periapical granuloma is used to define apical bony lesions smaller than 3 mm at their maximum intra‐bony diameter, and the term apical periodontal cysts for the larger lesions. We recommend that these terminologies and parameters be used as a standard in future studies. This will make inter‐observer and inter‐population comparisons more accurate. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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