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The llama (; or (:ˈʒama)) (''Lama glama'') is a domesticated South American camelid, widely used as a meat and pack animal by Andean cultures since pre-Hispanic times. The height of a full-grown, full-size llama is tall at the top of the head, and can weigh between . At birth, a baby llama (called a ''cria'') can weigh between . Llamas typically live for 15–25 years, with some individuals surviving 30 years or more.〔 (【引用サイトリンク】title=Llama Characteristics )〕 〔 (【引用サイトリンク】title=Llama Facts 1 )〕 〔 (【引用サイトリンク】publisher=Twin Creeks Llamas )〕 They are very social animals and live with other llamas as a herd. The wool produced by a llama is very soft and lanolin-free. Llamas are intelligent and can learn simple tasks after a few repetitions. When using a pack, they can carry about 25% to 30% of their body weight for 8–13 km (5–8 miles).〔 (【引用サイトリンク】publisher=Oklahoma State University )〕 The name ''llama'' (in the past also spelled 'lama' or 'glama') was adopted by European settlers from native Peruvians.〔Oxford English Dictionary, 2nd edition, "''llama''"〕 Llamas appear to have originated from the central plains of North America about 40 million years ago. They migrated to South America about three million years ago. By the end of the last ice age (10,000–12,000 years ago), camelids were extinct in North America.〔 As of 2007, there were over seven million llamas and alpacas in South America, and due to importation from South America in the late 20th century, there are now over 158,000 llamas and 100,000 alpacas in the United States and Canada.〔 (【引用サイトリンク】author=South Central Llama Association )〕 == Classification == Lamoids, or llamas (as they are more generally known as a group), consist of the vicuña (''Vicugna vicugna'', prev. ''Lama vicugna''), guanaco (''Lama guanicoe''), Suri alpaca, and Huacaya alpaca (''Vicugna pacos'', prev. ''Lama guanicoe pacos''), and the domestic llama (''Lama guanicoe glama''). Guanacos and vicuñas live in the wild, while alpacas – as well as llamas – exist only as domesticated animals. Although early writers compared llamas to sheep, their similarity to the camel was soon recognized. They were included in the genus ''Camelus'' along with alpaca in the ''Systema Naturae'' (1758) of Linnaeus. They were, however, separated by Cuvier in 1800 under the name of ''lama'' along with the guanaco.〔(【引用サイトリンク】url=http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=624943# )〕 Alpacas and vicuñas are in genus ''Vicugna''. The genera ''Lama'' and ''Vicugna'' are, with the two species of true camels, the sole existing representatives of a very distinct section of the Artiodactyla or even-toed ungulates, called Tylopoda, or "bump-footed", from the peculiar bumps on the soles of their feet. The Tylopoda consist of a single family, the Camelidae, and shares the order Artiodactyla with the Suina (pigs), the Tragulina (chevrotains), the Pecora (ruminants), and the Whippomorpha (hippos and cetaceans, which belong to Artiodactyla from a cladistic, if not traditional, standpoint). The Tylopoda have more or less affinity to each of the sister taxa, standing in some respects in a middle position between them, sharing some characteristics from each, but in others showing special modifications not found in any of the other taxa. The 19th-century discoveries of a vast and previously unexpected extinct Paleogene fauna of North America, as interpreted by paleontologists Leidy, Cope, and Marsh, aided understanding of the early history of this family. Llamas were not always confined to South America; abundant llama-like remains were found in Pleistocene deposits in the Rocky Mountains and in Central America. Some of the fossil llamas were much larger than current forms. Some species remained in North America during the last ice ages. North American llamas are categorized as a single extinct genus, ''Hemiauchenia''. Llama-like animals would have been a common sight 25,000 years ago, in modern-day California, Texas, New Mexico, Utah, Missouri, and Florida. The camelid lineage has a good fossil record. Camel-like animals have been traced from the thoroughly differentiated, modern species back through early Miocene forms. Their characteristics became more general, and they lost those that distinguished them as camelids; hence, they were classified as ancestral artiodactyls. No fossils of these earlier forms have been found in the Old World, indicating that North America was the original home of camelids, and that Old World camels crossed over via the Bering Land Bridge. The formation of the Isthmus of Panama three million years ago allowed camelids to spread to South America as part of the Great American Interchange, where they evolved further. Meanwhile, North American camelids died out at the end of the Pleistocene. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Llama」の詳細全文を読む スポンサード リンク
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