RUI: Quaternary Vertebrate Paleontology and Biogeography of Southeast Alaska

阿拉斯加东南部第四纪脊椎动物古生物学和生物地理学南达科他州大学蒂莫西·H·赫顿在理解北美人类和动物历史方面占据着至关重要的地位。在最近冰河时代的冰河时期，阿拉斯加中部通过白令大陆桥与亚洲相连，洲际旅行的障碍是覆盖加拿大大部分地区的大冰盖。阿拉斯加沿海是无冰地区之间旅行的合乎逻辑的路线，因为太平洋使该地区保持相对温暖，并提供持续的食物来源。直到最近，阿拉斯加东南部还没有发现第四纪化石，地质学家和生物学家认为，海岸已经完全被冰覆盖。但十年的研究表明，阿拉斯加东南部是一个哺乳动物和鸟类的北极群落的家园，即使在最后一次冰川盛期最冷的时期也是如此。从1990年开始，在威尔士亲王岛北部发现了含有冰河时代化石遗骸的石灰岩洞穴。其中最有成效的是在你的膝盖上的洞穴，它包含了跨越过去50,000年的几乎完整的化石记录，以及最广泛的阿拉斯加东南部(跨越过去10,000年)的考古记录。下一步是挖掘阿拉斯加东南部多个岛屿和大陆上的洞穴，以获得该地区在最后一次冰川盛期期间和之后的完整生物地理史。前景看好的脊椎动物化石地点位于最外层的岛屿(达尔岛、赫切塔岛和加冕群岛)和大陆兰盖尔镇附近。其他正在勘探的地区包括奇查戈夫岛北部的喀斯特地区和冰川湾国家公园。该项目的目标是在许多地点定位并进行小规模挖掘，希望找到与膝盖上的洞穴类似古老的其他化石沉积。人们还希望能够找到更多的考古记录，这将有助于确定该地区人类的古代，并评估阿拉斯加东南部在冰河时代是亚洲和北美之间旅行走廊的可能性。

RUI: Quaternary Vertebrate Paleontology and Biogeography of Southeast AlaskaTimothy H. HeatonUniversity of South DakotaEAR-0208247Southeast Alaska occupies a critical position in understanding the human and animal history of North America. During glacial epochs of the recent Ice Age, central Alaska was connected to Asia by the Bering Land Bridge, and the barriers to intercontinental travel were the large ice sheets that covered most of Canada. Coastal Alaska was a logical route for travel between ice-free areas because the Pacific Ocean kept the region relatively warm and provided a constant source of food. Until recently Quaternary fossils were unknown from Southeast Alaska, and geologists and biologists believed that the coast had been completely overridden with ice. But a decade of research has demonstrated that Southeast Alaska was home to an arctic community of mammals and birds that thrived even during the coldest period of the Last Glacial Maximum. Beginning in 1990, limestone caves containing Ice Age fossil remains were discovered on northern Prince of Wales Island. The most productive of these was On Your Knees Cave, which contained a nearly complete fossil record spanning the last 50,000 years as well as the most extensive archaeological record of Southeast Alaska (spanning the last 10,000 years). The next step is to excavate caves on multiple islands and on the mainland of Southeast Alaska to gain a complete biogeographic history of the region during and following the Last Glacial Maximum. Promising sites containing vertebrate fossils have been located on the outermost islands (Dall, Heceta, and Coronation Islands) and on the mainland near the town of Wrangell. Other regions being explored are karst areas of northern Chichagof Island and Glacier Bay National Park. The objectives of this project are to locate and conduct small-scale excavations at many sites in hopes of finding other fossil deposits of similar antiquity to On Your Knees Cave. It is also hoped that additional archaeological records can be located that will help determine the antiquity of humans in the region and assess the possibility that Southeast Alaska was a corridor for travel between Asia and North America during the Ice Age.