9 results match your criteria differences protoconid

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Enamel thickness variation in the deciduous dentition of extant large-bodied hominoids.

Am J Phys Anthropol 2020 11 7;173(3):500-513. Epub 2020 Aug 7.

Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona, USA.

Objectives: Enamel thickness features prominently in hominoid evolutionary studies. To date, however, studies of enamel thickness in humans, great apes, and their fossil relatives have focused on the permanent molar row. Comparatively little research effort has been devoted to tissue proportions within deciduous teeth. Read More

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November 2020

Endostructural morphology in hominoid mandibular third premolars: Discrete traits at the enamel-dentine junction.

J Hum Evol 2019 11 1;136:102670. Epub 2019 Oct 1.

School of Anthropology and Conservation, University of Kent, Canterbury, CT2 7NZ, UK; Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany; Evolutionary Studies Institute, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, 2000, Johannesburg, South Africa.

The mandibular third premolar (P) exhibits substantial differences in size and shape among hominoid taxa, and displays a number of discrete traits that have proven to be useful in studies of hominin taxonomy and phylogeny. Discrete traits at the enamel-dentine junction (EDJ) can be accurately assessed on moderately worn specimens, and often appear sharper than at the outer-enamel surface (OES). Here we use microtomography to image the P EDJ of a broad sample of extant apes, extinct hominins and modern humans (n = 100). Read More

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November 2019

Molar Microwear of Narrow-Headed Vole (Microtus gregalis Pall., 1779) Depending on the Feed Abrasiveness.

Dokl Biol Sci 2018 Jan 13;478(1):16-18. Epub 2018 Mar 13.

Ural State Medical University, Yekaterinburg, Russia.

In the narrow-headed vole, enamel microwear of the first mandibular molar (of the protoconid and entoconid anterior enamel wall) was studied under the laboratory conditions and at the fixed feed composition. The classic parameters and the area of the enamel prism lesion were taken into account. The enamel lesion patterns caused by the tooth-tooth and tooth-food interactions have been determined. Read More

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January 2018

Dental morphology of the Lesser Bamboo Rat, Cannomys badius (Rodentia, Spalacidae).

Zookeys 2012 17(228):69-75. Epub 2012 Oct 17.

Departamento de Paleobiología, Museo nacional de Ciencias naturales-CSIC, C/ José Gutiérrez Abascal 2, 28006 Madrid, Spain.

Cannomys and Rhizomys are the sole living genera of the tribe Rhizomyini (Rhizomyinae, Spalacidae, Rodentia), known in the fossil record since the Late Miocene. The dental morphology of fossil Rhizomyini has been described in detail but until recently such descriptions were unavailable for extant species. A detailed account of the morphology and dental wear pattern of the cheek teeth of Cannomys badius is provided here based on the examination of museum specimens. Read More

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November 2012

Brief communication: Molar development and crown areas in early Australopithecus.

Am J Phys Anthropol 2012 Aug 24;148(4):632-40. Epub 2012 May 24.

Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA.

Recent studies suggest that the hypodigms representing the two earliest Australopithecus (Au. anamensis and Au. afarensis) form an ancestor-descendant lineage. Read More

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A new species of Pliopithecus Gervais, 1849 (Primates: Pliopithecidae) from the Middle Miocene (MN8) of Abocador de Can Mata (els Hostalets de Pierola, Catalonia, Spain).

Am J Phys Anthropol 2010 Jan;141(1):52-75

Institut Català de Paleontologia, Universitat Autònoma de Barcelona, Edifici ICP, Campus de la UAB s / n, 08193 Cerdanyola del Vallès, Barcelona, Spain.

Pliopithecus (Pliopithecus) canmatensis sp. nov. is described from several Late Aragonian localities from Abocador de Can Mata (ACM) in els Hostalets de Pierola (Vallès-Penedès Basin, Catalonia, Spain), spanning from approximately 11. Read More

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January 2010

Intraspecific variation in M1 enamel development in modern humans: implications for human evolution.

Authors:
Patrick Mahoney

J Hum Evol 2008 Jul 25;55(1):131-47. Epub 2008 Apr 25.

Department of Archaeology, University of Sheffield, Sheffield S1 4ET, England, UK.

The timing and sequence of enamel development, as well as enamel thickness, was documented for individual cusps (protoconid, hypoconid, metaconid, entoconid) in 15 unworn permanent lower first molars (M(1)s) from a sample of modern human juveniles. These data were compared with previously published data for modern and fossil species reported in the literature. Crown formation in all teeth was initiated in the protoconid and completed in the hypoconid. Read More

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Enamel microstructure of the hominid KB 5223 from Kromdraai, South Africa.

Authors:
Rodrigo S Lacruz

Am J Phys Anthropol 2007 Feb;132(2):175-82

Institute for Human Evolution, School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa.

The Plio-Pleistocene site of Kromdraai, South Africa, is well known for the recovery of the holotype of Paranthropus robustus, one of nine individual hominids recovered from this site to date. Among the Kromdraai sample, the specimen KB 5223 comprises several isolated deciduous and permanent lower teeth assigned to Paranthropus, the only recognized genus at this site. However, a more recent analysis of this specimen suggested that it should be classified as Homo. Read More

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February 2007

Tooth and cusp size reduction in second molars.

Authors:
N Navsa

J Dent Assoc S Afr 1992 Jun;47(6):257-60

School of Dentistry, University of Witwatersrand, Johannesburg.

The present study examined the cusp reduction pattern of molars in two San-Hybrid groups, namely, the Vassekela and Barakwena. Cusp and crownbase area measurements were undertaken on enlarged photographs of maxillary molars and on camera lucida drawings of mandibular molars. The protocone values for the Barakwena were significantly larger than those of the Vassekela and were also the largest of the four maxillary molar cusps (especially in M2). Read More

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