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〔(【引用サイトリンク】url=http://library.sandiegozoo.org/factsheets/_extinct/eagle_%20daggetts/eagle.htm#behavior )〕 ''Buteogallus daggetti'' (Daggett's "eagle" or walking "eagle") is actually a rather long-legged species of hawk. Initially believed to be some sort of carrion-eating eagle, it was for some time placed in a distinct genus ''Wetmoregyps'' (meaning "Alexander Wetmore's vulture").〔Olson, Storrs L. "The" Walking Eagle" Wetmoregyps Daggetti Miller: A Scaled-up Version of the Savanna Hawk (Buteogallus meridionalis)." Ornithological Monographs (2007): 110-114.()〕 It probably resembled the modern-day savanna hawk with long legs and a body size that is roughly 40% larger. Many scientists think that it evolved long legs in response to a diet of snakes and reptiles, so it could keep its distance, similar to the secretarybird of Africa. Fossils of the Daggett's eagle are found in the La Brea and Carpinteria lagerstätte in southern California, and in Nuevo León in Mexico. The eagle lived anywhere from sea level to 2250 m. The Daggett Eagle also lived in grasslands, marshlands, savannas with some brush and ponds. It is also believed to have lived in forested habitat where it preyed on small vertebrates for food.〔〔Steadman, David W., and Jim I. Mead. "A Late Pleistocene bird community at the northern edge of the tropics in Sonora, Mexico." The American Midland Naturalist 163.2 (2010): 423-441. ()〕 It is thought that the females of this species were quite larger than the males, based on the size of fossils.It is believed that the extant savanna hawk is attracted to fire, whereas smaller species flee, and it is thought that Daggett's eagle might have had a similar behavior. Daggett's eagle became extinct about 13,000 years ago, in the Pleistocene epoch.〔 ''Physical characteristics'' How Do We Know This? Careful study of fossil bone or tooth anatomy yields much exact information about placement and strength of muscles, tendons, ligaments, nerves, and blood vessels. In rare cases, skin, hair, or feather impressions or actual tissue is preserved. Body weight is more difficult to gauge because fat leaves no impression on the skeleton. (Ferguson-Lees & Christie 2001) (Miller 1915) (Olson 2007) Estimated Body Size: *Body Weight: 3,000 g (6.6 lb) *Body Length: 64 – 90 cm (31 in) *Tail Length: 26 -32-2 cm (11 in) *Pelage: unknown ''Behavior and ecology'' How Do We Know This? Since direct observation of a fossil animal's behavior isn't possible, paleontologists use comparison and contrast with living animals for guidance. Tracks can sometimes reveal further clues (Olson 2007) (Steadman & Martin 1984) Interspecies interaction: * The extinction of many large birds of prey, especially scavengers, in the Pleistocene may have been related to extinction of large mammals (no carrion left to feed upon). (Steadman and Martin 1984) * Daggett's Eagles may have been scavengers (Steadman and Martin 1984), although some researchers think a purely scavenging lifestyle is not likely (Olson 2007) * Daggett's Eagles may have depended for habitat on large grazing animals that kept grassland habitats open (Olson 2007) * The Savannah Hawk, which closely resembles the Daggett's Eagle in body proportions, is attracted to the edge of fires as many smaller species flee (Ferguson-Lees and Christie 2001). Did Daggett's Eagles have the same behavior? (Olson 2007) ==References== 〔(【引用サイトリンク】url=http://www.sdzsafaripark.org/education/elephant_curriculum111209.pdf )〕 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「Buteogallus daggetti」の詳細全文を読む スポンサード リンク
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