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481.
Wim Van Neer 《International Journal of Osteoarchaeology》1993,3(2):119-127
An evaluation is given of the value for seasonality studies of incremental growth in the pectoral spines of the Nile catfish Clarias gariepinus. The subfossil spines used for this study are from a Byzantino-Islamic site in Syria, and probably all derive from animals captured on the floodplain during the yearly inundation of the nearby Orontes river, although only 45 per cent of the spines could be recognized as deriving from fish captured during that period. It is believed that the inability to date accurately the season of capture of the other specimens is due to disadvantages inherent in the growth cycle of the fish. For the moment it is possible to determine the season of death only of individuals that were taken during a period of rapid growth. 相似文献
482.
483.
ydrn Palubeckait Rimantas Jankauskas Jesper Boldsen 《International Journal of Osteoarchaeology》2002,12(3):189-201
Numerous studies and various interpretations of the prevalence of linear enamel hypoplasias (LEH) based on populations living in different cultural and economic conditions are causing some confusion and raising doubts about whether or not such LEH are reliable indicators of life conditions. An analysis of LEH prevalence patterns was performed on the adults of three populations: Tirup—a Danish Medieval rural population of the 12–14th centuries (131 individuals), Subačiaus str. in Vilnius—a Lithuanian Late Medieval urban population of the 16–17th centuries (88 individuals), and the aristocracy—a Lithuanian pooled sample population from several churches of the 15–18th centuries (66 individuals). Statistical testing of the influence of population affinity, sex and age at death was also performed. Since the same investigator scored all the samples, possible inter‐observer error bias was minimized. In all the populations, LEH formation ages were similar. Statistically significant sex differences were found only in the aristocratic sample (with higher male frequency). It was found that the town population was characterized by the highest frequency of affected individuals, with the highest severity and highest number of stress episodes per individual. A reliable relationship with age at death was found only in the town sample: individuals with more numerous and more marked LEH had shorter life expectancies in adulthood. Different “most vulnerable years” for subsequent life expectancies were noted for different populations. A tentative explanation of these differences could be the pooled effect of differential morbidity and mortality. It seems that the rural population experienced the highest morbidity and nutrition deficiency as well as the highest child mortality whereas, in the urban sample, high morbidity was accompanied by a lower child mortality. Both lower morbidity and mortality seem to be characteristic for the aristocracy. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
484.
Christopher M. Nicholson 《Environmental Archaeology》2020,25(4):381-396
ABSTRACT Climate niches that modern humans and earlier hominin ancestors occupied have changed dramatically over time, but the extent of those changes has gone largely undocumented. This study investigates the manner in which the realised hominin climate niche has expanded, contracted, or stayed stationary across four time periods (Last Interglacial, Last Glacial Maximum, Mid-Holocene, and 1950–2000) in Western Eurasia. Using spatially gridded general circulation model data and site locations this study examines climate variables from archaeological sites and current Western Eurasian cities to describe both the regional Western Eurasian fundamental and realised climate niches. Changes between the three prehistoric periods and modern-day time period are analysed by calculating each realised niche breadth, overlap, position, and variance. Results indicate that as global temperatures cooled from the Last Interglacial to Last Glacial Maximum, populations expanded their climate niche breadth beyond that of earlier Neanderthal groups, shifting toward regions with less seasonal variation. Conversely, Mid-Holocene humans, who saw the proliferation of both agriculture and population, contracted their realised climate niche space. The contraction and expansion of realised climate niche space illustrates how hominins have evolved the capacity to shift their niche through changes to their subsistence strategy and adaptations to overall climatic conditions. 相似文献