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991.
Dental wear and intrabony lesions were evaluated in a sample of 225 skulls (136 male) of pre‐contact New Zealand Maoris. The degree and direction of surface wear was scored according to the method of Molnar ( Molnar 1971 . Human tooth wear, tooth function and cultural variability. American Journal of Physical Anthropology34: 175–190) and revealed severe surface loss in both males and females with horizontal wear being the dominant pattern (62.4% male, 57.5% female). The width of coronal tissue above the pulp chamber, as well as the maximum depth and width of periapical lesions, was measured from both standard radiographs and digital images. The high prevalence of periapical pathology in the Maori underlined the extreme nature of dental wear in these people. It is postulated that this degree of tooth loss may be attributable to a change in diet from large birds to marine‐dependence, the introduction of the kumara to New Zealand, dental erosion and finally, to the excessive masticatory forces exerted by a robust facial complex on normally sized teeth. Fenestrated lesions were highly prevalent (83% of skulls) and were centered mostly on the maxilla, with an even distribution among tooth classes. The finding of periapical lesions in teeth with minimal observable wear was attributed to traumatic occlusion. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
992.
993.
We report δ18O and δ13C data from modern carbonate in soils and dung samples from 3 recently abandoned livestock corrals in northern Kenya. Calcium carbonate content is higher within ∼5 cm depth that contains a mixture of dung and surface soils of corrals than in soils below 5 cm depth. We radiocarbon dated carbonates from 0.5 to 40 cm depths in two corrals and one control site. Surface carbonates (0.5 cm) from the two corrals were formed from modern carbon (>1955) when the corrals were active, while all other carbon is >16,000 years (BP) old. Shallow carbonate is also enriched in 18O (δ18O up to 3.0‰) and depleted in 13C (δ13C up to −12.0‰) with respect to carbonate at deeper levels and at two control sites. The δ18O and δ13C of soil carbonates (δ18OSC and δ13CSC respectively) in corrals are inversely correlated for depths up to about 15 cm where organic carbon is greater than 0.5%. Below that depth, there is a positive correlation between δ18OSC and δ13CSC values, similar to that observed in a control site.  相似文献   
994.
995.
This paper deals with the origins and functions of the Swedish consular service in Southern Europe between 1720 and 1815. It is argued that establishment of the consular service was a necessary part of the Swedish policy of trade expansion. Consuls acted partly as commission agents of Swedish merchant and shipowners, because Sweden lacked established trading contacts in the area. Partly, consuls had official diplomatic functions, especially in North Africa. The consular service is conceived as an institutional arrangement reducing transaction costs of Swedish agents. This article suggests that reduction in protection costs in particular was a significant competitive advantage of Swedish merchants and shipowners and was due to peace treaties with the Barbary states in North Africa and Sweden's neutrality in the 18th‐century great power conflicts.  相似文献   
996.
Chlorozyga, a new genus of Australian Tournaisian (Early Carboniferous) caenogastropod, is proposed and assigned to the Imoglobidae. Chlorozyga has a larval shell like Imogloba from the Early Carboniferous of North America but differs in teleoconch morphology. As in Imogloba, the initial whorl of Chlorozyga is openly coiled, a feature unknown in Mesozoic and Recent caenogastropods. However, Chlorozyga and Imogloba belong to the Caenogastropoda, given their multi-whorled orthostrophic larval shells.  相似文献   
997.
998.
A long‐standing debate in archaeology concerns the sources of technological diversification among prehistoric hunter‐gatherers. This includes the study of the emergence and spread of pressure blade technology in Northern Europe during the Early Holocene. Until now, there has been little technological study of lithic collections from the East Baltic region, and our knowledge of the development and spread of this technology in the area is inadequate. This article presents for the first time a technological analysis of lithic assemblages from seven Early and Middle Mesolithic sites in the territory of present‐day Latvia, offering new possibilities for discussing pressure blade technology and research objectives connected with it. Furthermore, variation in elements of this technology is explored in relation to raw‐material characteristics through experimental flint knapping. Finally, the factors influencing diversity in craft traditions, as well as large‐scale communication and shifting spheres of interaction within Northern Europe during the Mesolithic, are discussed.  相似文献   
999.
1000.
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