title: From 'third pole' to north pole: a Himalayan origin for the arctic fox.
abstract: The 'third pole' of the world is a fitting metaphor for the Himalayan-Tibetan Plateau, in allusion to its vast frozen terrain, rivalling the Arctic and Antarctic, at high altitude but low latitude. Living Tibetan and arctic mammals share adaptations to freezing temperatures such as long and thick winter fur in arctic muskox and Tibetan yak, and for carnivorans, a more predatory niche. Here, we report, to our knowledge, the first evolutionary link between an Early Pliocene (3.60-5.08 Myr ago) fox, Vulpes qiuzhudingi new species, from the Himalaya (Zanda Basin) and Kunlun Mountain (Kunlun Pass Basin) and the modern arctic fox Vulpes lagopus in the polar region. A highly hypercarnivorous dentition of the new fox bears a striking resemblance to that of V. lagopus and substantially predates the previous oldest records of the arctic fox by 3-4 Myr. The low latitude, high-altitude Tibetan Plateau is separated from the nearest modern arctic fox geographical range by at least 2000 km. The apparent connection between an ancestral high-elevation species and its modern polar descendant is consistent with our 'Out-of-Tibet' hypothesis postulating that high-altitude Tibet was a training ground for cold-environment adaptations well before the start of the Ice Age.
authors.affiliation: Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu Province 210046, People's Republic of China Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA xwang@nhm.org.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA.
authors.forename: Zhijie Jack
authors.initials: ZJ
authors.lastname: Tseng
authors.affiliation: Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.affiliation: The George C. Page Museum, 5801 Wilshire Boulevard, Los Angeles, CA 90036, USA.
authors.forename: Gary T
authors.initials: GT
authors.lastname: Takeuchi
authors.affiliation: Gansu Provincial Museum, Lanzhou, Gansu Province 730050, People's Republic of China.
authors.forename: Guangpu
authors.initials: G
authors.lastname: Xie
mesh_terms: D000818:Animals; D001110:Arctic Regions; D005075:Biological Evolution; D005580:Fossils / Q000033:anatomy & histology*; D005589:Foxes / Q000033:anatomy & histology* / Q000145:classification*; D005843:Geography; D008334:Mandible / Q000033:anatomy & histology; D018609:Tibet; D014070:Tooth / Q000033:anatomy & histology
keywords: Canidae; Himalaya; Pliocene; Tibet; arctic fox; zoogeography