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Sarah K. Brown Christyann M. Darwent Benjamin N. Sacks 《Journal of archaeological science》2013,40(2):1279-1288
The domestic dog fulfills many functions for their human companions, such as hauling, guarding, and protection. Consequently, humans have taken dogs to nearly every corner of the globe. Recent translocations of Western dogs stemming from the Victorian era dog fancy have erased some of the ancient genetic signatures of these earlier migrations. Here we used DNA of ancient and modern dogs from the North American Arctic of Alaska and Greenland to assess their genetic continuity in time and space. We successfully sequenced 23 archaeological (ca. AD 1250–1910) and recent (ca. AD 1930–1990) surface-collected Canis bone and tooth samples and compared them to 51 modern Inuit Sled Dogs and to published sequences of modern Alaskan Malamutes (and additional Inuit Sled Dogs) to test for evidence of lineage replacement or genetic continuity through time. Ancient samples from Alaska and Greenland and modern sequences from Greenland all contained a high frequency of haplotype A31, which was previously described only in modern North American Arctic dogs. Thus, A31 was a common thread tying the entire North American Arctic together prior to European colonization and, in the Eastern Arctic, indicates genetic continuity between past and present dogs as well. However, A31 is rare in modern Alaskan dogs, consistent with post-colonization replacement by Eurasian matrilines. 相似文献
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Gregory D. Edgecombe Maxwell R. Banks Doris M. Banks 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):235-257
Eastonian trilobite faunas of the Gordon Group in Tasmania include the new species Ceraurinella oepiki, Erratencrinurus trippi, and Pliomerina trisulcata, as well as a reedocalymeninid probably allied to Sarrabesia Hammann & Leone, 1997. Ceraurinella and Erratencrinurus have not previously been reported from Australia, the former being predominantly Laurentian but also known from NE China, the Himalaya, and Vietnam, and the latter mostly Baltic/Laurentian. Peri-Gondwanan species of Ceraurinella appear to form a clade, within which Tasmanian and Indian (central Himalayan) taxa are closest relatives. 相似文献
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