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''Homo erectus '' (meaning "upright man", from the Latin ''ērigere'', "to put up, set upright") is an extinct species of hominid that lived throughout most of the Pleistocene geological epoch. Its earliest fossil evidence dates to 1.9 million years ago and the most recent to 70,000 years ago. Its extinction is linked by some scientists to the Toba super-eruption catastrophe, but no sufficient case has been made to date for the idea. It is generally thought that ''H. erectus'' originated in Africa and spread from there, migrating throughout Eurasia as far as Georgia, India, Sri Lanka, China and Indonesia.〔Chauhan, Parth R. (2003) ("Distribution of Acheulian sites in the Siwalik region" ) in ''An Overview of the Siwalik Acheulian & Reconsidering Its Chronological Relationship with the Soanian – A Theoretical Perspective''. assemblage.group.shef.ac.uk〕 But other scientists posit that the species rose first, or separately, in Asia. Debate also continues about the classification, ancestry, and progeny of ''Homo erectus'', especially vis-à-vis ''Homo ergaster'', with two major positions: 1) ''H. erectus'' is the same species as ''H. ergaster'', and thereby ''H. erectus'' is a direct ancestor of the later hominins including ''Homo heidelbergensis'', ''Homo neanderthalensis'', and ''Homo sapiens''; or, 2) it is in fact an Asian species distinct from African ''H. ergaster''.〔〔See overview of theories on human evolution.〕〔Klein, R. (1999). ''The Human Career: Human Biological and Cultural Origins''. Chicago: University of Chicago Press, ISBN 0226439631.〕 There is also another view—an alternative to 1): some palaeoanthropologists consider ''H. ergaster'' to be a variety, that is, the "''African''" variety, of ''H. erectus'', and they offer the labels "''Homo erectus sensu stricto''" (strict sense) for the Asian species and "''Homo erectus sensu lato''" (broad sense) for the greater species comprising both Asian and African populations. A new debate appeared in 2013, with the documentation of the Dmanisi skulls.〔(Skull suggests three early human species were one : Nature News & Comment )〕 Considering the large morphological variation among all Dmanisi skulls, researchers now suggest that several early human ancestors variously classified, for example, as ''Homo ergaster'', or ''Homo rudolfensis'', and perhaps even ''Homo habilis'', should instead be designated as ''Homo erectus''. ==Origin== The first hypothesis of origin is that ''Homo erectus'' rose from the Australopithecina in East Africa sometime during—or perhaps even before—the Early Pleistocene geological epoch, which itself dates to 2.58 million years ago (''see'' below, at African genesis, re earlier date at Ledi-Geraru Research Area). From there it migrated, in part, by 2.0 mya, probably as a result of broad desertifying conditions developing then in eastern and northern Africa; it joined the migrations through the "Saharan pump" and dispersed around much of the Old World. The fossil record shows that its development from about 1.8 mya to one mya was widely distributed: in Africa (Lake Turkana and Olduvai Gorge), the Transcaucasus (Dmanisi in Georgia), Indonesia (Sangiran, Central Java and Trinil, East Java), and in Vietnam, China (Zhoukoudian and Shaanxi), and India. The second hypothesis is that ''H. erectus'' evolved in Eurasia and then migrated to Africa. They occupied the Dmanisi site from 1.85 million to 1.77 million years ago, which was about the same time or slightly before their earliest evidence in Africa.〔(New discovery suggests Homo erectus originated from Asia ). Dnaindia.com. 8 June 2011.〕 There are several proposed explanations of the dispersal of ''H. erectus georgicus''—including whether or not Africa is the source). 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「Homo erectus」の詳細全文を読む スポンサード リンク
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