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51.
The ancient Egyptians mummified an abundance of cats during the Late Period (664 - 332 BC). The overlapping morphology and sizes of developing wildcats and domestic cats confounds the identity of mummified cat species. Genetic analyses should support mummy identification and was conducted on two long bones and a mandible of three cats that were mummified by the ancient Egyptians. The mummy DNA was extracted in a dedicated ancient DNA laboratory at the University of California - Davis, then directly sequencing between 246 and 402 bp of the mtDNA control region from each bone. When compared to a dataset of wildcats (Felis silvestris silvestris, F. s. tristrami, and F. chaus) as well as a previously published worldwide dataset of modern domestic cat samples, including Egypt, the DNA evidence suggests the three mummies represent common contemporary domestic cat mitotypes prevalent in modern Egypt and the Middle East. Divergence estimates date the origin of the mummies' mitotypes to between two and 7.5 thousand years prior to their mummification, likely prior to or during Egyptian Predyanstic and Early Dynastic Periods. These data are the first genetic evidence supporting that the ancient Egyptians used domesticated cats, F. s. catus, for votive mummies, and likely implies cats were domesticated prior to extensive mummification of cats.  相似文献   
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Many historical geographers would claim Sauer to be one of them. Yet, with the exception of his Foreword to historical geography (1941) he made no major declaration of his interest in the sub-discipline. This paper attempts to examine Sauer's attitude to the time element in geography through a close appraisal of his published work but particularly through his hitherto unpublished correspondence. It soon becomes evident that Sauer changed his ideas during his long working life, and that it is difficult to disentangle Sauer's philosophy about the time element in geography from his philosophy about life, particularly within university circles in the United States, and within American society in general. Sauer's comment to a student in 1936 that historical geography “is of course the apple of my eye” would seem to be demonstrated amply, but that historical geography was not a conventional methodology so much as a flexible metaphor to encompass the study of man on earth through time. It was also the vehicle for some of his prime concerns; scholarship, independent thought, opposition to bureaucracy, concern for human values and environmental quality, and deep distaste for the technological and scientific “fix”, particularly the solutions offered by the social sciences. It might repay contemporary historical geographers to take a close look at Sauer's academic and intellectual values.  相似文献   
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