Tedford Richard H, Harington C Richard
Division of Paleontology, American Museum of Natural History, New York, New York 10024, USA.
Nature. 2003 Sep 25;425(6956):388-90. doi: 10.1038/nature01892.
A peat deposit on Ellesmere Island, Nunavut, Canada, allows a unique glimpse of the Early Pliocene terrestrial biota north of the Arctic Circle. The peat accumulated in a beaver pond surrounded by boreal larch forest near regional tree line in coastal hills close to the Arctic Ocean. The ecological affinities of the plant and beetle remains contained in the peat indicate that winter temperatures on Ellesmere Island were nearly 15 degrees C higher and summer temperatures 10 degrees C higher than they are today. Here we show that the mammalian remains buried in the peat represent mainly taxa of Eurasiatic zoogeographic and phyletic affinities, including the first North American occurrence of a meline badger (Arctomeles). This deposit contains direct evidence of the composition of an Early Pliocene (4-5 million years ago) arctic mammalian fauna during an active period of interchange between Asia and North America.
加拿大努纳武特地区埃尔斯米尔岛上的一处泥炭矿床，让人得以独特地一瞥北极圈以北上新世早期的陆地生物群。泥炭堆积在北冰洋附近沿海山丘靠近区域树木线的一处由北方落叶松林环绕的海狸池塘中。泥炭中所含植物和甲虫残骸的生态亲缘关系表明，埃尔斯米尔岛的冬季温度比现在高近15摄氏度，夏季温度比现在高10摄氏度。我们在此表明，埋在泥炭中的哺乳动物残骸主要代表具有欧亚动物地理和系统发育亲缘关系的类群，包括北美首次出现的貂熊（Arctomeles）。该矿床包含了上新世早期（400 - 500万年前）亚洲和北美活跃交流时期北极哺乳动物群组成的直接证据。
