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Two significant events in the late Holocene history of Madagascar were (a) the arrival of people, and (b) the loss of nearly two dozen species of land vertebrates in the socalled “subfossil extinctions”. The consensus is that the faunal losses occurred shortly subsequent to human arrival, but the timing of these events is poorly constrained. The minimum age for initial human presence on the island may now be set at approximately 2000 bp, on the basis of AMS 14C dates for human-modified femora of extinct dwarf hippos from SW Madagascar. Assuming that this date also marks the beginning of deleterious human interactions with the subfossil fauna, and assuming that this fauna became completely extinct by 900 bp, the width of the anthropogenic “extinction window” may have been as long as c. 1000 a. This estimate, nearly twice the length of previous ones, is close to the unadjusted minimum for the duration of the terminal Pleistocene extinction event in the Americas. Whether or not this length of time comports with theoretical expectations of a “blitzkrieg” pattern of losses is uncertain, but greater refinement in dating the end of the subfossil extinctions is unlikely to produce radically shorter estimates of duration. 相似文献
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本报告发表的是中国社会科学院考古研究所考古科技实验研究中心碳十四实验室在2006年到2007年期间测定的30个考古数据。数据表示方式同此前所发报告。为方便应用另做几点说明如下。1.碳十四年代半衰期按5568年计算。2.校正年代所用程序为OxCal,校正曲线为1998年公布版本。3.与以往报告相同,所给年代误差范围均为±16,年代范围的概率分布为68.2%。4.由于树轮年代校正曲线各区段形状不同,校 相似文献
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