|
''Australopithecus sediba'' is a species of ''Australopithecus'' of the early Pleistocene, identified based on fossil remains dated to about 2 million years ago. The species is known from six skeletons discovered in the Malapa Fossil Site at the Cradle of Humankind World Heritage Site in South Africa, one a juvenile male (MH1 also called "Karabo",〔 〕 the holotype), an adult female (MH2, the paratype), an adult male, and three infants.〔 The fossils were found together at the bottom of the Malapa Cave, where they apparently fell to their death, and have been dated to between 1.977 and 1.980 million years ago.〔(African fossils put new spin on human origins story ) - BBC News - Jonathan Amos - Retrieved 9 September 2011.〕 Over 220 fragments from the species have been recovered to date. The partial skeletons were initially described in two papers in the journal ''Science'' by American and South African palaeo-anthropologist Lee R. Berger from the University of the Witwatersrand, Johannesburg and colleagues as a newly discovered species of early human ancestor called ''Australopithecus sediba'' ("sediba" meaning "natural spring" or "well" in the Sotho language).〔 MH1 is unarticulated and 34% complete if skeletal elements known to be in an unprepared block are included (59.6% if small elements are excluded) while MH2 is 45.6% complete (again 59.6% excluding small elements) and exhibits partial articulation. ''Australopithecus sediba'' may have lived in savannas but ate fruit and other foods from the forest—behavior similar to modern-day savanna chimpanzees. The conditions in which the individuals were buried and fossilized were extraordinary, permitting the extraction of plant phytoliths from dental plaque. ==Discovery== The first specimen of ''A. sediba'' was found by paleoanthropologist Lee Berger's nine-year-old son, Matthew, on August 15, 2008. While exploring near his father's dig site in the dolomitic hills north of Johannesburg, on the Malapa Nature Reserve, Matthew stumbled upon a fossilized bone.〔 The boy alerted his father to the find, who could not believe what he saw — a hominid clavicle. Upon turning the block over, "sticking out of the back of the rock was a mandible with a tooth, a canine, sticking out. And I almost died", he later recalled.〔 The fossil turned out to belong to a juvenile male, whose skull was discovered in March 2009 by Berger's team.〔 The find was announced to the public on April 8, 2010. Also found at the Malapa archeological site were a variety of animal fossils, including saber-toothed cats, mongooses, and antelopes.〔 Berger and geologist Paul Dirks speculated that the animals might have fallen into a deep "death-trap", perhaps lured by the scent of water.〔 The bodies may have then been swept into a pool of water with a sandy bottom and rich with lime, allowing the remains to become fossilized.〔 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「Australopithecus sediba」の詳細全文を読む スポンサード リンク
|