The Eastern Limit of Beringia: Mammoth Remains from Banks and Melville Islands, Northwest Territories

Аннотация

Two mammoth fossils (presumably woolly mammoth, Mammuthus primigenius) from northwestern Banks and southwestern Melville Islands, Northwest Territories, Canada, have been radiocarbon-dated to the Last Glacial Maximum (LGM), at 21 000 and 22 000 14CYBP, respectively. These fossils not only are the northernmost mammoth records for North America, but also indicate that the Mammoth Steppe and Beringia extended eastward at least to Ballast Brook, Banks Island (74.3? N, 123.1? W), and possibly to the Cape James Ross area of Melville Island (75.7? N, 114.4? W). The specimens, a tibia and a tusk, probably represent woolly mammoths that moved northeastward from the Mackenzie Delta region during the LGM, when worldwide sea level had dropped about 120 m, leaving large tracts of sea bottom exposed off the Beaufort Sea coast and the west coast of Banks Island (then largely clear of glacial ice). Evidently herb tundra rich enough to supply the mammoths’ needs characterized the regional landscape at that time. It is proposed that the term “Beringia” be used in the broad sense where evidence exists for a land connection between Asia and North America, regardless of its cause(s) and its supposed westerly or easterly limits, and that “Beringia” be used in a standard way: followed by its geological age in parentheses. Also, the term “Bering Isthmus” seems preferable to the commonly used “Bering Land Bridge.”