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''Homo'' is the genus that comprises the species ''Homo sapiens'', which includes modern humans, as well as several extinct species classified as ancestral to or closely related to modern humans—as for examples ''Homo habilis'' and ''Homo neanderthalensis''. The genus is about 2.8 million years old;〔 Also ISBN 0-521-46786-1 (paperback)〕 it first appeared as its earliest species ''Homo habilis'', which emerged from the genus ''Australopithecus'', which itself had previously split from the lineage of the genus ''Pan'', the chimpanzees. ''Homo'' is the only genus assigned to the subtribe Hominina which, with the subtribes Australopithecina and Panina, comprise the tribe Hominini (see evolutionary tree below). All species of the genus ''Homo'' plus those species of the australopithecines that arose ''after'' the split from ''Pan'' are called hominins. The line to the earliest members of ''Homo'' made final separation from the lineage of ''Pan'' by late Miocene or early Pliocene times—with date estimates by several specialists ranging from 13 million years ago 〔Arnason U, Gullberg A, Janke A (December 1998). "Molecular timing of primate divergences as estimated by two nonprimate calibration points". J. Mol. Evol. 47 (6): 718–27. doi:10.1007/PL00006431. PMID 9847414.〕 to as recent as four million years ago—which (latter) date was soon rejected by some; 〔Patterson N, Richter DJ, Gnerre S, Lander ES, Reich D (June 2006). "Genetic evidence for complex speciation of humans and chimpanzees". Nature 441 (7097): 1103–8. doi:10.1038/nature04789. PMID 16710306〕 〔Wakeley J (March 2008). "Complex speciation of humans and chimpanzees". Nature 452 (7184): E3–4; discussion E4. doi:10.1038/nature06805. PMID 18337768. "Patterson et al. suggest that the apparently short divergence time between humans and chimpanzees on the X chromosome is explained by a massive interspecific hybridization event in the ancestry of these two species. However, Patterson et al. do not statistically test their own null model of simple speciation before concluding that speciation was complex, and—even if the null model could be rejected—they do not consider other explanations of a short divergence time on the X chromosome. These include natural selection on the X chromosome in the common ancestor of humans and chimpanzees, changes in the ratio of male-to-female mutation rates over time, and less extreme versions of divergence with gene flow. I therefore believe that their claim of hybridization is unwarranted."〕 see current estimates regarding complex speciation. ''Homo erectus'' appeared about two million years ago in East Africa (where it is dubbed ''Homo ergaster'') and, in several early migrations, it spread throughout Africa and Eurasia. It was likely the first hominin to live in a hunter-gatherer society and to control fire. An adaptive and successful species, ''Homo erectus'' persisted for almost 2 million years before suddenly becoming extinct about 70,000 years ago (0.07 Ma)—perhaps a casualty of the Toba supereruption catastrophe. ''Homo sapiens sapiens'', or ''anatomically'' modern humans, emerged about 200,000 years ago (0.2 Ma) in East Africa (see Omo remains). There is division among scholars as to when ''H. s. sapiens'' became ''behaviorally'' modern; the debate is: modern behavior developed 1) simultaneously with anatomical development, or 2) separately, and was complete by 50,000 years ago (see Modern human behavior). ''Homo sapiens sapiens'' is the only surviving species of the genus Homo; all others have become extinct. Modern humans migrated from Africa as recently as 60,000 years ago, and during Upper Paleolithic times they spread throughout Africa and Eurasia, Oceania, and the Americas; and they encountered archaic humans en route of their migrations. Some archaic humans outside Africa survived alongside modern humans until about 40,000 years ago (''see H. neanderthalensis''),〔(), BBC〕 and possibly until as late as the times of the Epipaleolithic culture (about 12,000 years ago). DNA analysis provides evidence of interbreeding between archaic and modern humans. ==Name== :''See Hominidae for an overview of taxonomy.'' The Latin noun ''homō'' (genitive ''hominis'') means "human being" or "man" in the generic sense of "human being, mankind".〔The word "human" itself is from Latin ''humanus'', an adjective formed on the root of ''homo'', thought to derive from a Proto-Indo-European word for "earth" reconstructed as '. (dhghem ) The American Heritage Dictionary of the English Language: Fourth Edition. 2000.〕 The binomial name ''Homo sapiens'' was coined by Carl Linnaeus (1758).〔. Note: In 1959, Linnaeus was designated as the lectotype for ''Homo sapiens'' (Stearn, W. T. 1959. "The background of Linnaeus's contributions to the nomenclature and methods of systematic biology", ''Systematic Zoology'' 8 (1): 4-22, p. 4) which means that following the nomenclatural rules, ''Homo sapiens'' was validly defined as the animal species to which Linnaeus belonged.〕 Names for other species of the genus were introduced beginning in the second half of the 19th century (''H. neanderthalensis'' 1864, ''H. erectus'' 1892). 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」の詳細全文を読む スポンサード リンク
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