Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China.
Science. 2011 Sep 2;333(6047):1285-8. doi: 10.1126/science.1206594.
Ice Age megafauna have long been known to be associated with global cooling during the Pleistocene, and their adaptations to cold environments, such as large body size, long hair, and snow-sweeping structures, are best exemplified by the woolly mammoths and woolly rhinos. These traits were assumed to have evolved as a response to the ice sheet expansion. We report a new Pliocene mammal assemblage from a high-altitude basin in the western Himalayas, including a primitive woolly rhino. These new Tibetan fossils suggest that some megaherbivores first evolved in Tibet before the beginning of the Ice Age. The cold winters in high Tibet served as a habituation ground for the megaherbivores, which became preadapted for the Ice Age, successfully expanding to the Eurasian mammoth steppe.
更新世的大型冰期动物长期以来一直被认为与全球变冷有关，它们对寒冷环境的适应，如体型较大、毛发较长和扫雪结构，以猛犸象和披毛犀最为典型。这些特征被认为是对冰盖扩张的反应而进化出来的。我们报告了一个来自喜马拉雅山西部高海拔盆地的上新世哺乳动物组合，其中包括一种原始的披毛犀。这些新的西藏化石表明，一些大型食草动物在冰河时代开始之前首先在西藏进化。高海拔的西藏冬季寒冷，成为大型食草动物的适应地，它们为冰河时代做好了准备，成功地扩展到了欧亚大陆的猛犸象草原。
