Changes

=== Origin ===

=== Origin ===

The scientific study of [[human evolution]] encompasses the development of the genus ''[[Homo (genus)|Homo]]'', but usually involves studying other [[hominidae|hominids]] and [[homininae|hominines]] as well, such as ''[[Australopithecus]]''. "Modern humans" are defined as the ''Homo sapiens''  [[species]], of which the only extant [[subspecies]] is ''Homo sapiens sapiens''; ''[[Homo sapiens idaltu]]'' (roughly translated as "elder wise human"), the other known subspecies, is extinct.<ref>[http://www.anth.ucsb.edu/projects/human/# Human evolution: the fossil evidence in 3D], by Philip L. Walker and Edward H. Hagen, Dept of Anthropology, University of California, Santa Barbara, retrieved [[April 5]], [[2005]].</ref> Anatomically modern humans appear in the fossil record in Africa about 130,000 years ago.<ref>[http://www.mnh.si.edu/anthro/humanorigins/ha/sap.htm Human Ancestors Hall: ''Homo Sapiens''] - URL retrieved [[October 13]], [[2006]]</ref><ref>{{cite journal |author=Alemseged Z, Coppens Y, Geraads D |title=Hominid cranium from Omo: Description and taxonomy of Omo-323-1976-896 |journal=Am J Phys Anthropol |volume=117 |issue=2 |pages=103-12 |year=2002 |id=PMID 11815945}}</ref>

The scientific study of [[human evolution]] encompasses the development of the genus ''[[Homo (genus)|Homo]]'', but usually involves studying other [[hominidae|hominids]] and [[homininae|hominines]] as well, such as ''[[Australopithecus]]''. "Modern humans" are defined as the ''Homo sapiens''  [[species]], of which the only extant [[subspecies]] is ''Homo sapiens sapiens''; ''[[Homo sapiens idaltu]]'' (roughly translated as "elder wise human"), the other known subspecies, is extinct. [http://www.anth.ucsb.edu/projects/human/#] Anatomically modern humans appear in the fossil record in Africa about 130,000 years ago.[http://www.mnh.si.edu/anthro/humanorigins/ha/sap.htm]  

The closest living relatives of ''Homo sapiens'' are two distinct species of the genus Pan: the [[Bonobo]] (''Pan paniscus'') and the [[Common Chimpanzee]] (''Pan troglodytes''). These species share the same common ancestor. The main difference between them is the social organization: [[matriarchal]] for the Bonobo and [[patriarchal]] for the Common Chimpanzee. Full [[genome]] sequencing resulted in the conclusion that "after 6.5 [[million]]&nbsp;years of separate evolution, the differences between bonobo/chimpanzee and human are just 10 times greater than those between two unrelated people and 10 times less than those between rats and mice". In fact, 95 per cent of the DNA sequence is identical between the two ''Pan'' species and human.<ref>[[Frans de Waal]], ''Bonobo''. Berkeley: University of California Press, 1997. ISBN 0-520-20535-9 [http://www.2think.org/bonobo.shtml]</ref><ref>{{cite journal | author=Britten RJ | title=Divergence between samples of chimpanzee and human DNA sequences is 5%, counting indels | url=http://www.pnas.org/cgi/content/full/99/21/13633 | journal=Proc Natl Acad Sci U S A | year=2002 | pages=13633-5 | volume=99 | issue=21 | id=PMID 12368483}}</ref><ref>{{cite journal | author = Wildman D, Uddin M, Liu G, Grossman L, Goodman M | title = Implications of natural selection in shaping 99.4% nonsynonymous DNA identity between humans and chimpanzees: enlarging genus Homo. | url=http://www.pnas.org/cgi/content/full/100/12/7181 | journal = Proc Natl Acad Sci U S A | volume = 100 | issue = 12 | pages = 7181-8 | year = 2003 | id = PMID 12766228}}</ref><ref>{{cite journal | author = Ruvolo M | title = Molecular phylogeny of the hominoids: inferences from multiple independent DNA sequence data sets. | url=http://mbe.oxfordjournals.org/cgi/reprint/14/3/248 | journal = Mol Biol Evol | volume = 14 | issue = 3 | pages = 248-65 | year = 1997 | id = PMID 9066793}}</ref> It has been estimated that the human [[lineage (evolution)|lineage]] diverged from that of chimpanzees about five million&nbsp;years ago, and from [[gorilla]]s about  eight million&nbsp;years ago. However, a hominid skull discovered in [[Chad]] in 2001, classified as ''[[Sahelanthropus tchadensis]]'', is approximately seven million&nbsp;years old, which may indicate an earlier divergence.<ref>{{cite journal | author = Brunet M, Guy F, Pilbeam D, Mackaye H, Likius A, Ahounta D, Beauvilain A, Blondel C, Bocherens H, Boisserie J, De Bonis L, Coppens Y, Dejax J, Denys C, Duringer P, Eisenmann V, Fanone G, Fronty P, Geraads D, Lehmann T, Lihoreau F, Louchart A, Mahamat A, Merceron G, Mouchelin G, Otero O, Pelaez Campomanes P, Ponce De Leon M, Rage J, Sapanet M, Schuster M, Sudre J, Tassy P, Valentin X, Vignaud P, Viriot L, Zazzo A, Zollikofer C | title = A new hominid from the Upper Miocene of  Chad, Central Africa.  | url=http://www.nature.com/nature/journal/v418/n6894/full/nature00879.html | journal = Nature | volume = 418 | issue = 6894 | pages = 145-51 | year = 2002 | id = PMID 12110880}}</ref>

The closest living relatives of ''Homo sapiens'' are two distinct species of the genus Pan: the [[Bonobo]] (''Pan paniscus'') and the [[Common Chimpanzee]] (''Pan troglodytes''). These species share the same common ancestor. The main difference between them is the social organization: [[matriarchal]] for the Bonobo and [[patriarchal]] for the Common Chimpanzee. Full [[genome]] sequencing resulted in the conclusion that "after 6.5 [[million]]&nbsp;years of separate evolution, the differences between bonobo/chimpanzee and human are just 10 times greater than those between two unrelated people and 10 times less than those between rats and mice". In fact, 95 per cent of the DNA sequence is identical between the two ''Pan'' species and human.[[Frans de Waal]], ''Bonobo'' ISBN 0-520-20535-9 [http://www.2think.org/bonobo.shtml [http://www.pnas.org/cgi/content/full/99/21/13633] [url=http://www.pnas.org/cgi/content/full/100/12/7181][http://mbe.oxfordjournals.org/cgi/reprint/14/3/248]| It has been estimated that the human [[lineage (evolution)|lineage]] diverged from that of chimpanzees about five million&nbsp;years ago, and from [[gorilla]]s about  eight million&nbsp;years ago. However, a hominid skull discovered in [[Chad]] in 2001, classified as ''[[Sahelanthropus tchadensis]]'', is approximately seven million&nbsp;years old, which may indicate an earlier divergence. [http://www.nature.com/nature/journal/v418/n6894/full/nature00879.html]

The [[Recent African Origin]] (RAO), or "out-of-Africa", hypothesis proposes that modern humans evolved in Africa and later [[human migration|migrated]] outwards to replace hominids in other parts of the world. Evidence from [[Archaeogenetics]] accumulating since the 1990s has lent strong support to RAO and has marginalized the  competing [[multiregional hypothesis]],  which proposed that modern humans evolved, at least in part, from independent hominid populations.<ref>Eswaran, Vinayak, Harpending, Henry & Rogers, Alan R. ''[http://www.sciencedirect.com/science/article/B6WJS-4G3SC6X-1/2/aae7c2810f0d87628e228363c0e1bd66 Genomics refutes an exclusively African origin of humans]'', Journal of Human Evolution, In Press, Corrected Proof, retrieved [[May 6]], [[2005]].</ref>

The [[Recent African Origin]] (RAO), or "out-of-Africa", hypothesis proposes that modern humans evolved in Africa and later [[human migration|migrated]] outwards to replace hominids in other parts of the world. Evidence from [[Archaeogenetics]] accumulating since the 1990s has lent strong support to RAO and has marginalized the  competing [[multiregional hypothesis]],  which proposed that modern humans evolved, at least in part, from independent hominid populations. [http://www.sciencedirect.com/science/article/B6WJS-4G3SC6X-1/2/aae7c2810f0d87628e228363c0e1bd66]  

Geneticists Lynn Jorde and [[Henry Harpending]] of the [[University of Utah]] proposed that the variation in human DNA is minute compared to that of other species. They also propose that during the [[Late Pleistocene]], the human population was reduced to a small number of breeding pairs — no more than 10,000 and possibly as few as 1,000 — resulting in a very small residual gene pool. Various reasons for this hypothetical bottleneck have been postulated, one of those is the [[Toba catastrophe theory]].

Geneticists Lynn Jorde and [[Henry Harpending]] of the [[University of Utah]] proposed that the variation in human DNA is minute compared to that of other species. They also propose that during the [[Late Pleistocene]], the human population was reduced to a small number of breeding pairs — no more than 10,000 and possibly as few as 1,000 — resulting in a very small residual gene pool. Various reasons for this hypothetical bottleneck have been postulated, one of those is the [[Toba catastrophe theory]].

Human evolution is characterized by a number of important morphological, developmental, physiological and behavioral changes which have taken place since the split between the last common ancestor of ''Homo'' and ''Pan''. The primary change, both in terms of chronology and in terms of it being the trait that defines the human [[subtribe]] the [[Hominina]], was the evolution of a bipedal locomotor adaptation from an arboreal or semi-arboreal locomotor adaptation, with all its attendant adaptations, such as a valgus knee, low intermembral index (long legs relative to the arms) and reduced upper body strength.{{Fact|date=November 2007}} Following this was the evolution of a larger [[Cranial capacity|brain cavity]] and brain itself, which is typically 1,400&nbsp;cm³ in modern humans; over twice that of a chimpanzee or gorilla. Other significant morphological changes included: the evolution of a power and precision grip;{{Fact|date=November 2007}} a reduced masticatory system; a reduction of the [[canine tooth]]; and the descent of the [[larynx]] and [[hyoid bone]], making speech possible. With respect to development, the pattern of human postnatal brain growth differs from that of other apes ([[heterochrony]]), allowing for an extended period of social learning and [[language acquisition]] in juvenile humans. [[Physical anthropology|Physical anthropologists]] argue that a reorganization of the structure of the brain is more important than cranial expansion itself.  One important physiological change in humans was the evolution of hidden estrus or [[concealed ovulation]] in females, which may have coincided with the evolution of important behavioral changes, such as [[pair bond]]ing. Another significant behavioral change includes the development of [[material culture]], or the (over time) increasingly wide variety of human-made objects which are used to manipulate humans' physical and social environments. How all these changes are related and what their role is in the evolution of complex social organization and culture are matters of ongoing debate.<ref>Boyd, Robert & Silk, Joan B. (2003). ''How Humans Evolved''. New York: Norton & Company. ISBN 0-393-97854-0.</ref><ref>Dobzhansky, Theodosius (1963). ''Anthropology and the natural sciences-The problem of human evolution'', ''Current Anthropology '4'' (2): 138-148.</ref>

Human evolution is characterized by a number of important morphological, developmental, physiological and behavioral changes which have taken place since the split between the last common ancestor of ''Homo'' and ''Pan''. The primary change, both in terms of chronology and in terms of it being the trait that defines the human [[subtribe]] the [[Hominina]], was the evolution of a bipedal locomotor adaptation from an arboreal or semi-arboreal locomotor adaptation, with all its attendant adaptations, such as a valgus knee, low intermembral index (long legs relative to the arms) and reduced upper body strength. Following this was the evolution of a larger [[Cranial capacity|brain cavity]] and brain itself, which is typically 1,400&nbsp;cm³ in modern humans; over twice that of a chimpanzee or gorilla. Other significant morphological changes included: the evolution of a power and precision grip;{{Fact|date=November 2007}} a reduced masticatory system; a reduction of the [[canine tooth]]; and the descent of the [[larynx]] and [[hyoid bone]], making speech possible. With respect to development, the pattern of human postnatal brain growth differs from that of other apes ([[heterochrony]]), allowing for an extended period of social learning and [[language acquisition]] in juvenile humans. [[Physical anthropology|Physical anthropologists]] argue that a reorganization of the structure of the brain is more important than cranial expansion itself.  One important physiological change in humans was the evolution of hidden estrus or [[concealed ovulation]] in females, which may have coincided with the evolution of important behavioral changes, such as [[pair bond]]ing. Another significant behavioral change includes the development of [[material culture]], or the (over time) increasingly wide variety of human-made objects which are used to manipulate humans' physical and social environments. How all these changes are related and what their role is in the evolution of complex social organization and culture are matters of ongoing debate.(''How Humans Evolved'', ISBN 0-393-97854-0]

=== Rise of civilization ===

=== Rise of civilization ===

The most widely accepted view among current [[anthropology|anthropologists]] is that ''Homo sapiens'' originated in the African [[savanna]] around 200,000 BP ([[Before Present]]), descending from ''[[Homo erectus]]'', had inhabited [[Eurasia]] and [[Oceania]] by 40,000 BP, and finally inhabited the [[Americas]] approximately 10,000&nbsp;years ago.<ref>Templeton, Alan (2002). [http://cogweb.ucla.edu/ep/Templeton_02.html "Out of Africa again and again"] ''Nature'' 416: 45 - 51.</ref> They displaced ''[[Homo neanderthalensis]]'' and other species descended from ''Homo erectus'' (which had inhabited Eurasia as early as 2 million&nbsp;years ago) through more successful reproduction and competition for resources.

The most widely accepted view among current [[anthropology|anthropologists]] is that ''Homo sapiens'' originated in the African [[savanna]] around 200,000 BP ([[Before Present]]), descending from ''[[Homo erectus]]'', had inhabited [[Eurasia]] and [[Oceania]] by 40,000 BP, and finally inhabited the [[Americas]] approximately 10,000&nbsp;years ago. [http://cogweb.ucla.edu/ep/Templeton_02.html "Out of Africa again and again"] They displaced ''[[Homo neanderthalensis]]'' and other species descended from ''Homo erectus'' (which had inhabited Eurasia as early as 2 million&nbsp;years ago) through more successful reproduction and competition for resources.

Up until only around 10,000 years ago, all humans lived as [[hunter-gatherer]]s (with some communities persisting until this day). They generally lived in small, [[nomad]]ic groups. The advent of [[agriculture]] prompted the [[Neolithic Revolution]]. Access to food surplus led to the formation of permanent human settlements, the [[domestication]] of animals, and the use of [[metalworking|metal tools]]. Agriculture also encouraged [[trade]] and cooperation, leading to complex societies. [[Village]]s developed into thriving [[civilization]]s in regions such as the [[Middle East]]'s [[Fertile Crescent]].

Up until only around 10,000 years ago, all humans lived as [[hunter-gatherer]]s (with some communities persisting until this day). They generally lived in small, [[nomad]]ic groups. The advent of [[agriculture]] prompted the [[Neolithic Revolution]]. Access to food surplus led to the formation of permanent human settlements, the [[domestication]] of animals, and the use of [[metalworking|metal tools]]. Agriculture also encouraged [[trade]] and cooperation, leading to complex societies. [[Village]]s developed into thriving [[civilization]]s in regions such as the [[Middle East]]'s [[Fertile Crescent]].