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This is a list of the native wild mammal species recorded in South America. South America's terrestrial mammals fall into three distinct groups. The marsupials and xenarthrans are 'old-timers', their ancestors having been present on the continent since at least the very early Cenozoic Era. During the early Cenozoic, South America's only land connection was to Antarctica, so it was effectively cut off from most of the world; as the fragments of Gondwana continued to separate, this connection was lost, leaving South America an island continent. Caviomorph rodents and monkeys arrived as 'waif dispersers' by rafting across the Atlantic from Africa in the Eocene epoch, 35 million or more years ago. All the remaining nonflying mammals of South America are recent arrivals, having migrated from North America via Central America during the past seven million years as part of the Great American Interchange; this invasion, which peaked around three million years ago, was made possible when the formation of the volcanic Isthmus of Panama bridged North and South America. The newcomers out-competed and drove to extinction many unique mammals that had evolved during South America's long period of isolation, as well as some species from other classes (e.g., terror birds). South America suffered another major loss of mammal species in the Quaternary extinction event, which started around 12500 cal BP, at roughly the time of arrival of Paleoindians, and may have lasted up to several thousand years. At least 37 genera of mammals were eliminated, including most of the megafauna. While South America currently has no megaherbivore species weighing more than 1000 kg, prior to this event it had a menagerie of about 25 of them (consisting of gomphotheres, camelids, ground sloths, glyptodontids, and toxodontids – 75% of these being 'old-timers'), dwarfing Africa's present and recent total of 6. Anthropogenic climate change and the damage to its ecosystems resulting from the rapid recent growth of the human population pose a further threat to South America's biodiversity. The list consists of those species found in the nations or overseas territories of continental South America (including their island possessions, such as the Galápagos), as well as in Trinidad and Tobago and the Falkland Islands; Panama is not included. As of May 2012, the list contains 1331 species, 340 genera, 62 families and 15 orders. Of the taxa from nonflying, nonmarine groups (992 species, 230 genera, 40 families and 12 orders), 'old-timers' comprise 14% of species, 15% of genera, 20% of families and 42% of orders; African immigrants make up 38% of species, 30% of genera, 40% of families and 17% of orders; North American invaders constitute 49% of species 55% of genera, 40% of families and 50% of orders. At the order level, the 'old-timers' are overrepresented because of their ancient local origins, while the African immigrants are underrepresented because of their 'sweepstakes' mode of dispersal. Of the species, 8 are extinct, 29 are critically endangered, 64 are endangered, 111 are vulnerable, 64 are near-threatened, and 255 are data-deficient. Mammal species presumed extinct since AD 1500 (eight or nine cases) are included. Domestic species (e.g., the guinea pig, alpaca, and llama) and introduced species are not listed. NOTE: this list is inevitably going to be incomplete, since new species are continually being recognized via discovery or reclassification. Places to check for missing species include the Wikipedia missing mammal species list, including recently removed entries, and the species listings in the articles for mammalian genera, especially those of small mammals such as rodents or bats. The following tags are used to highlight each species' conservation status as assessed by the IUCN: The IUCN status of all listed species except bats was last updated during the period from March to June 2009; bats were updated in September 2009. ==Subclass: Theria== 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「List of South American mammals」の詳細全文を読む スポンサード リンク
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