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{{Dablink|This article is about the general evolution of [[humans]]. For a timeline see [[Timeline of human evolution]].}}
[[File:Human evolution scheme.svg|thumb|250px|Simplified scheme of human evolution]]
'''Human evolution''', or '''''anthropogenesis''''', is the origin and [[evolution]] of ''[[Homo sapiens]]'' as a distinct [[species]] from other [[hominid]]s, [[great apes]] and [[placental]] [[mammals]]. The study of human evolution encompasses many [[scientific]] disciplines, including [[physical anthropology]], [[primatology]], [[archaeology]], [[linguistics]] and [[genetics]].<ref>{{cite journal |author=Heng HH |title=The genome-centric concept: resynthesis of evolutionary theory |journal=Bioessays |volume=31 |issue=5 |pages=512–25 |year=2009 |month=May |pmid=19334004 |doi=10.1002/bies.200800182}}</ref>

The term "human" in the context of human evolution refers to the genus ''[[Homo (genus)|Homo]]'', but studies of human evolution usually include other [[hominid]]s, such as the [[Australopithecines]]. The genus ''Homo'' had diverged from the Australopithecines by about 2.3 to 2.4 million years ago in Africa.<ref name="encylopediahumanevolution">{{cite book|title= The Cambridge Encyclopedia of Human Evolution | author=Stringer, C.B. | chapter=Evolution of early humans | editors=Steve Jones, Robert Martin & David Pilbeam (eds.)| year=1994 | publisher= Cambridge University Press | location= Cambridge |isbn= 0-521-32370-3 | page=242}} Also ISBN 0-521-46786-1 (paperback)</ref><ref name="evolutionthe1st4billionyears">{{cite book|title= Evolution: The First Four Billion Years| author=McHenry, H.M | chapter=Human Evolution | editors=Michael Ruse & Joseph Travis | year=2009 | publisher= The Belknap Press of Harvard University Press | location = Cambridge, Massachusetts |isbn=978-0-674-03175-3 | page=265}}</ref> Scientists have estimated that humans branched off from their common ancestor with [[chimpanzee]]s - the only other living hominins - about 5–7 million years ago. Several species of ''Homo'' evolved and are now [[Species#Extinct organisms|extinct]]. These include ''[[Homo erectus]]'', which [[habitat|inhabited]] Asia, and ''[[Homo neanderthalensis]]'', which inhabited Europe. [[Archaic Homo sapiens|Archaic ''Homo sapiens'']] evolved between 400,000 and 250,000 years ago.

The dominant view among scientists concerning the origin of [[anatomically modern humans]] is the [[recent African origin of modern humans|"Out of Africa"]] or recent African origin hypothesis,<ref>{{cite web|url=http://www.sciencemag.org/cgi/content/summary/sci;308/5724/921g |title=Out of Africa Revisited - 308 (5724): 921g - Science |doi=10.1126/science.308.5724.921g |publisher=Sciencemag.org |date=2005-05-13 |accessdate=2009-11-23}}</ref><ref>{{cite web|author=Nature |url=http://www.nature.com/nature/journal/v423/n6941/full/423692a.html |title=Access : Human evolution: Out of Ethiopia |publisher=Nature |date=2003-06-12 |accessdate=2009-11-23}}</ref><ref>{{cite web|url=http://www.actionbioscience.org/evolution/johanson.html |title=Origins of Modern Humans: Multiregional or Out of Africa? |publisher=ActionBioscience |date= |accessdate=2009-11-23}}</ref><ref>{{cite web|url=http://www.asa3.org/ASA/education/origins/migration.htm |title=Modern Humans - Single Origin (Out of Africa) vs Multiregional |publisher=Asa3.org |date= |accessdate=2009-11-23}}</ref> which argues that ''H. sapiens'' arose in Africa and migrated out of the continent around 50-100,000 years ago, replacing populations of ''H. erectus'' in Asia and ''H. neanderthalensis'' in Europe. Scientists supporting the alternative [[multiregional hypothesis]] argue that ''H. sapiens'' evolved as geographically separate but interbreeding populations stemming from a worldwide migration of ''H. erectus'' out of Africa nearly 2.5 million years ago.

==History of ideas about human evolution==
The word ''homo'', the name of the biological genus to which humans belong, is [[Latin]] for "human". It was chosen originally by [[Carolus Linnaeus]] in his classification system. The word "human" is from the Latin ''humanus'', the adjectival form of ''homo''. The Latin "homo" derives from the Indo-European root, ''dhghem'', or "earth".<ref>{{Cite book|chapter=dhghem|title=The American Heritage Dictionary of the English Language|edition=4th|publisher=Houghton Mifflin Company|year=2000|url=http://www.bartelby.org/61/roots/IE104.html|format={{dead link|date=August 2009}}}}</ref>

Carolus Linnaeus and other scientists of his time also considered the [[great ape]]s to be the closest relatives of human beings due to [[morphology (biology)|morphological]] and [[anatomical]] similarities. The possibility of linking humans with earlier apes by descent only became clear after 1859 with the publication of [[Charles Darwin]]'s ''[[On the Origin of Species]]''. This argued for the idea of the evolution of new species from earlier ones. Darwin's book did not address the question of human evolution, saying only that "Light will be thrown on the origin of man and his history".

The first debates about the nature of human evolution arose between [[Thomas Huxley]] and [[Richard Owen]]. Huxley argued for human evolution from apes by illustrating many of the similarities and differences between humans and apes and did so particularly in his 1863 book ''[[Evidence as to Man's Place in Nature]]''. However, many of Darwin's early supporters (such as [[Alfred Russel Wallace]] and [[Charles Lyell]]) did not agree that the origin of the mental capacities and the moral sensibilities of humans could be explained by [[natural selection]]. Darwin applied the theory of evolution and [[sexual selection]] to humans when he published ''[[The Descent of Man, and Selection in Relation to Sex|The Descent of Man]]'' in 1871.<ref>{{cite book | last = Darwin | first = Charles | title = The Descent of Man, and Selection in Relation to Sex | year = 1871. This edition published 1981, with Introduction by John Tyler Bonner & Robert M. May| publisher = Princeton University Press | location = Princeton, New Jersey | isbn = 0-691-02369-7.}}</ref>

A major problem was the lack of fossil intermediaries. It was only in the 1920s that such [[fossil]]s were discovered in Africa. In 1925, [[Raymond Dart]] described [[Australopithecus africanus]]. The [[type specimen]] was the [[Taung Child]], an Australopithecine infant discovered in a cave. The child's remains were a remarkably well-preserved tiny skull and an [[endocranial cast]] of the individual's brain. Although the brain was small (410&nbsp;cm³), its shape was rounded, unlike that of chimpanzees and gorillas, and more like a modern human brain. Also, the specimen showed short [[canine tooth|canine teeth]], and the position of the [[foramen magnum]] was evidence of [[bipedal]] locomotion. All of these traits convinced Dart that the Taung baby was a bipedal human ancestor, a transitional form between apes and humans.

The [[Ape#History of hominoid taxonomy|classification of humans and their relatives]] has changed considerably over time. The gracile Australopithecines are now thought to be ancestors of the genus ''Homo'', the group to which modern humans belong. Both Australopithecines and ''Homo sapiens'' are part of the tribe [[Hominini]]. Recent data suggests Australopithecines were a diverse group and that ''A. africanus'' may not be a direct ancestor of modern humans. Reclassification of Australopithecines that originally were split into either [[gracile]] or [[robust]] varieties has put the latter into a family of its own, ''[[Paranthropus]]''. Taxonomists place humans, Australopithecines and related species in the same family as other great apes, in the [[Hominidae]].

{{:Human evolution/Species chart}}

==Before ''Homo''==
===Evolution of apes===
{{Refimprovesect|date=August 2009}}
[[File:PlesiadapisNewZICA.png|thumb|Plesiadapis]]
The evolutionary history of the [[primate]]s can be traced back 65 million years, as one of the oldest of all surviving placental mammal groups. The oldest known primate-like mammal species, the [[Plesiadapis]], come from North America, but they were widespread in Eurasia and Africa during the tropical conditions of the [[Paleocene]] and [[Eocene]].

[[File:Notharctus tenebrosus AMNH.jpg|thumb|Notharctus]]
With the beginning of modern climates, marked by the formation of the first Antarctic ice in the early [[Oligocene]] around 30 million years ago. A primate from this time was ''[[Notharctus]]''. Fossil evidence found in Germany in the 1980s was determined to be about 16.5 million years old, some 1.5 million years older than similar species from East Africa and challenging the original theory regarding human ancestry originating on the African continent.

David Begun<ref name = "Kordos-p17">{{cite journal |author=Kordos L, Begun DR |title=Primates from Rudabánya: allocation of specimens to individuals, sex and age categories |journal=J. Hum. Evol. |volume=40 |issue=1 |pages=17–39 |year=2001 |pmid=11139358 |doi=10.1006/jhev.2000.0437}}</ref> says that these primates flourished in Eurasia and that the lineage leading to the African apes and humans— including [[Dryopithecus]]—migrated south from Europe or Western Asia into Africa. The surviving tropical population, which is seen most completely in the upper Eocene and lowermost Oligocene fossil beds of the [[Fayum]] depression southwest of Cairo, gave rise to all living primates—[[lemur]]s of Madagascar, [[loris]]es of Southeast Asia, [[galago]]s or "bush babies" of Africa, and the [[anthropoid]]s; [[platyrrhine]]s or New World monkeys, and [[catarrhine]]s or Old World monkeys and the great apes and humans.

The earliest known catarrhine is ''[[Kamoyapithecus]]'' from uppermost Oligocene at Eragaleit in the northern Kenya Rift Valley, dated to 24 million years ago. Its ancestry is generally thought to be species related to ''[[Aegyptopithecus]]'', ''[[Propliopithecus]]'', and ''[[Parapithecus]]'' from the Fayum, at around 35 million years ago. There are no fossils from the intervening 11 million years.

[[File:Proconsul skeleton reconstitution (University of Zurich).JPG |thumb|Reconstructed tailless ''[[Proconsul (primate)|Proconsul]]'' skeleton]]
In the early [[Miocene]], after 22 million years ago, the many kinds of arboreally-adapted primitive catarrhines from East Africa suggest a long history of prior diversification. Fossils at 20 million years ago include fragments attributed to ''[[Victoriapithecus]]'', the earliest Old World Monkey. Among the genera thought to be in the ape lineage leading up to 13 million years ago are ''[[Proconsul (genus)|Proconsul]]'', ''[[Rangwapithecus]]'', ''[[Dendropithecus]]'', ''[[Limnopithecus]]'', ''[[Nacholapithecus]]'', ''[[Equatorius]]'', ''[[Nyanzapithecus]]'', ''[[Afropithecus]]'', ''[[Heliopithecus]]'', and ''[[Kenyapithecus]]'', all from East Africa. The presence of other generalized non-cercopithecids of middle Miocene age from sites far distant—''[[Otavipithecus]]'' from cave deposits in Namibia, and ''[[Pierolapithecus]]'' and ''[[Dryopithecus]]'' from France, Spain and Austria—is evidence of a wide diversity of forms across Africa and the Mediterranean basin during the relatively warm and equable climatic regimes of the early and middle Miocene. The youngest of the Miocene hominoids, ''[[Oreopithecus]]'', is from 9 million year old coal beds in Italy.

Molecular evidence indicates that the lineage of [[gibbon]]s (family [[Hylobatidae]]) became distinct from Great Apes between 18 and 12 million years ago, and that of [[orangutan]]s (subfamily Ponginae) became distinct from the other Great Apes at about 12 million years; there are no fossils that clearly document the ancestry of gibbons, which may have originated in a so-far-unknown South East Asian hominoid population, but fossil proto-orangutans may be represented by ''[[Ramapithecus]]'' from India and ''[[Griphopithecus]]'' from Turkey, dated to around 10 million years ago.

===Divergence of the human lineage from other Great Apes ===
Species close to the last common ancestor of gorillas, chimpanzees and humans may be represented by ''[[Nakalipithecus]]'' fossils found in Kenya and ''[[Ouranopithecus]]'' found in Greece. Molecular evidence suggests that between 8 and 4 million years ago, first the [[gorilla]]s, and then the chimpanzees (genus ''Pan'') split off from the line leading to the humans; human DNA is approximately 98.4% identical to that of chimpanzees when comparing single nucleotide polymorphisms (see [[Human evolutionary genetics]]). The fossil record of gorillas and chimpanzees is quite limited. Both poor preservation (rain forest soils tend to be acidic and dissolve bone) and [[sampling bias]] probably contribute to this problem.

Other [[Homininae|hominines]] likely adapted to the drier environments outside the equatorial belt, along with antelopes, hyenas, dogs, pigs, elephants, and horses. The equatorial belt contracted after about 8 million years ago. Fossils of these hominans - the species in the human lineage following divergence from the chimpanzees - are relatively well known. The earliest are ''[[Sahelanthropus tchadensis]]'' (7 Ma) and ''[[Orrorin tugenensis]]'' (6 Ma), followed by:
*''[[Ardipithecus]]'' (5.5–4.4 Ma), with species ''[[Ardipithecus kadabba|Ar. kadabba]]'' and ''[[Ardipithecus ramidus|Ar. ramidus]]'';
*''[[Australopithecus]]'' (4–2 Ma), with species ''[[Australopithecus anamensis|Au. anamensis]]'', ''[[Australopithecus afarensis|Au. afarensis]]'', ''[[Australopithecus africanus|Au. africanus]]'', ''[[Australopithecus bahrelghazali|Au. bahrelghazali]]'', and ''[[Australopithecus garhi|Au. garhi]]'';
*''[[Kenyanthropus]]'' (3–2.7 Ma), with species ''[[Kenyanthropus platyops]]''
*''[[Paranthropus]]'' (3–1.2 Ma), with species ''[[Paranthropus aethiopicus|P. aethiopicus]]'', ''[[Paranthropus boisei|P. boisei]]'', and ''[[Paranthropus robustus|P. robustus]]'';
*''Homo'' (2 Ma–present), with species ''[[Homo habilis]]'', ''[[Homo rudolfensis]]'', ''[[Homo ergaster]]'', ''[[Homo georgicus]]'', ''[[Homo antecessor]]'', ''[[Homo cepranensis]]'', ''[[Homo erectus]]'', ''[[Homo heidelbergensis]]'', ''[[Homo rhodesiensis]]'', ''[[Neanderthal|Homo neanderthalensis]]'', ''[[Homo sapiens idaltu]]'', ''[[Archaic Homo sapiens]]'', ''[[Homo floresiensis]]''

==Genus ''Homo''==

''Homo sapiens'' is the only [[extant taxon|non-extinct]] species of its genus, ''Homo''. There were other ''Homo'' species, all of which are now extinct. While some of these other species might have been ancestors of ''H. sapiens'', many were likely our "cousins", having speciated away from our ancestral line.<ref>{{cite journal |author=Strait DS, Grine FE, Moniz MA |title=A reappraisal of early hominid phylogeny |journal=J. Hum. Evol. |volume=32 |issue=1 |pages=17–82 |year=1997 |pmid=9034954 |doi=10.1006/jhev.1996.0097}}</ref> There is not yet a consensus as to which of these groups should count as separate species and which as subspecies. In some cases this is due to the paucity of fossils, in other cases it is due to the slight differences used to classify species in the ''Homo'' genus. The [[Sahara pump theory]] (describing an occasionally passable "wet" [[Sahara Desert]]) provides an explanation of the early variation in the genus ''Homo''.

Based on [[archaeological]] and [[paleontological]] evidence, it has been possible to infer the ancient dietary practices of various ''Homo'' species and to study the role of diet in physical and behavioral evolution within ''Homo''.<ref name="isbn0195183460">{{cite book |title=Evolution of the Human Diet: The Known, the Unknown, and the Unknowable |author=Ungar, Peter S. |publisher=Oxford University Press |location=US |year=2006 |isbn=0195183460 |page=432}}</ref><ref name="isbn0897897366">{{cite book |author=Ungar, Peter S. & Teaford, Mark F. |title=Human Diet: Its Origin and Evolution |publisher=Bergin & Garvey |location=Westport, CT |year=2002 |isbn=0897897366 |page=206}}</ref><ref name="isbn0897895169-Bogin">{{cite book |last=Bogin |first=Barry |editor=Romanucci-Ross, Lola; Moerman, Daniel E.; & Tancredi, Laurence R. |title=The Anthropology of Medicine: From Culture to Method |edition=3 |year=1997 |publisher=Bergen and Garvey |location=South Hadley, Mass. |isbn=0897895169 |pages=96–142 |chapter=The evolution of human nutrition |chapterurl=http://web.archive.org/web/20031203003838/http://citd.scar.utoronto.ca/ANTAO1/Projects/Bogin.html}}</ref><ref>{{cite journal |author=Barnicot NA |title=Human nutrition: evolutionary perspectives |journal=Integr Physiol Behav Sci |volume=40 |issue=2 |pages=114–17 |year=2005, April/June |pmid=17393680 |url= |doi=10.1007/BF02734246}}</ref><ref>{{cite journal |author=Leonard WR, Snodgrass JJ, Robertson ML |title=Effects of brain evolution on human nutrition and metabolism |journal=Annu Rev Nutr. |volume=27 |pages=311–27 |year=2007 |pmid=17439362 |doi=10.1146/annurev.nutr.27.061406.093659 |url=http://www.pinniped.net/LeonardARN.pdf|format=PDF|accessdate=2008-12-29}}</ref>

===''Habilis''===
''[[H. habilis]]'' lived from about 2.4 to 1.4 [[annum|Ma]]. ''H. habilis'', the first species of the genus ''Homo'', evolved in South and East Africa in the late [[Pliocene]] or early [[Pleistocene]], 2.5–2 Ma, when it diverged from the Australopithecines. ''H. habilis'' had smaller molars and larger brains than the Australopithecines, and made tools from stone and perhaps animal bones. One of the first known hominids, it was nicknamed 'handy man' by its discoverer, [[Louis Leakey]] due to its association with [[stone tools]]. Some scientists have proposed moving this species out of ''Homo'' and into ''Australopithecus'' due to the morphology of its skeleton being more adapted to [[arboreal|living on trees]] rather than to [[bipedalism|moving on two legs]] like ''H. sapiens''.<ref> Wood, B. & Collard, M. (1999) The changing face of Genus Homo. Evol. Anth. 8(6) 195-207</ref>

===''Rudolfensis'' and ''Georgicus''===
These are proposed species names for fossils from about 1.9–1.6 Ma, the relation of which with ''H. habilis'' is not yet clear.
*[[Homo rudolfensis|''H. rudolfensis'']] refers to a single, incomplete skull from Kenya. Scientists have suggested that this was another ''H. habilis'', but this has not been confirmed.<ref>{{cite journal |author=Wood B |title='Homo rudolfensis' Alexeev, 1986-fact or phantom? |journal=J. Hum. Evol. |volume=36 |issue=1 |pages=115–8 |year=1999 |pmid=9924136 |doi=10.1006/jhev.1998.0246}}</ref>
* [[Homo georgicus|''H. georgicus'']], from [[Georgia (country)|Georgia]], may be an intermediate form between ''H. habilis'' and ''H. erectus'',<ref>{{cite journal |author=Gabounia L. de Lumley M. Vekua A. Lordkipanidze D. de Lumley H. |title= Discovery of a new hominid at Dmanisi (Transcaucasia, Georgia) |journal=Comptes Rendus Palevol, |volume=1 |issue=4 |pages=243–53 |year=2002|doi=10.1016/S1631-0683(02)00032-5}}</ref> or a sub-species of ''H. erectus''.<ref>{{cite journal |author=Lordkipanidze D, Vekua A, Ferring R, ''et al.'' |title=A fourth hominin skull from Dmanisi, Georgia |journal=The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology |volume=288 |issue=11 |pages=1146–57 |year=2006 |pmid=17031841 |doi=10.1002/ar.a.20379}}</ref>

===''Ergaster'' and ''Erectus''===
[[Image:Humanevolutionchart.png|One current view of the temporal and geographical distribution of hominid populations.<ref>Genetic Analysis of Lice Supports Direct Contact between Modern and Archaic Humans Reed DL, Smith VS, Hammond SL, Rogers AR, Clayton DH PLoS Biology Vol. 2, No. 11, e340 doi:10.1371/journal.pbio.0020340 http://biology.plosjournals.org/perlserv/?request=slideshow&type=figure&doi=10.1371/journal.pbio.0020340&id=15540</ref> Other interpretations differ mainly in the taxonomy and geographical distribution of hominid species.|thumb|325px]]

The first fossils of ''Homo erectus'' were discovered by Dutch physician [[Eugene Dubois]] in 1891 on the [[Indonesia]]n island of [[Java]]. He originally gave the material the name ''Pithecanthropus erectus'' based on its morphology that he considered to be intermediate between that of humans and apes.<ref>{{cite journal |author=Turner W |title=On M. Dubois' Description of Remains recently found in Java, named by him Pithecanthropus erectus: With Remarks on so-called Transitional Forms between Apes and Man |journal=Journal of anatomy and physiology |volume=29 |issue=Pt 3 |pages=424–45 |year=1895 |pmid=17232143 |doi= |pmc=1328414}}</ref> ''[[Homo erectus|H. erectus]]'' lived from about 1.8 Ma to about 70,000 years ago (which would indicate that they were probably wiped out by the [[Toba catastrophe]]; however, [[Homo erectus soloensis]] and [[Homo floresiensis]] survived it). Often the early phase, from 1.8 to 1.25 Ma, is considered to be a separate species, ''[[Homo ergaster|H. ergaster]]'', or it is seen as a subspecies of ''H. erectus'', ''[[Homo erectus|Homo erectus ergaster]]''.

In the early Pleistocene, 1.5–1 Ma, in Africa, Asia, and Europe, some populations of ''Homo habilis'' are thought to have evolved larger brains and made more elaborate stone tools; these differences and others are sufficient for anthropologists to classify them as a new species, ''H. erectus''. In addition ''H. erectus'' was the first human ancestor to walk truly upright.<ref>{{cite journal |author=Spoor F, Wood B, Zonneveld F |title=Implications of early hominid labyrinthine morphology for evolution of human bipedal locomotion |journal=Nature |volume=369 |issue=6482 |pages=645–8 |year=1994 |pmid=8208290 |doi=10.1038/369645a0}}</ref> This was made possible by the evolution of locking knees and a different location of the [[foramen magnum]] (the hole in the skull where the spine enters). They may have used fire to cook their meat.

{{See also|Control of fire by early humans}}

A famous example of ''Homo erectus'' is [[Peking Man]]; others were found in Asia (notably in Indonesia), Africa, and Europe. Many paleoanthropologists now use the term ''H. ergaster'' for the non-Asian forms of this group, and reserve ''H. erectus'' only for those fossils that are found in Asia and meet certain skeletal and dental requirements which differ slightly from ''H. ergaster''.

===''Cepranensis'' and ''Antecessor''===
These are proposed as species that may be intermediate between ''H. erectus'' and ''H. heidelbergensis''.
* ''[[Homo antecessor|H. antecessor]]'' is known from fossils from Spain and England that are dated 1.2 Ma–500 [[annum|ka]].<ref>{{cite journal |author=Bermúdez de Castro JM, Arsuaga JL, Carbonell E, Rosas A, Martínez I, Mosquera M |title=A hominid from the lower Pleistocene of Atapuerca, Spain: possible ancestor to Neandertals and modern humans |journal=Science |volume=276 |issue=5317 |pages=1392–5 |year=1997 |pmid=9162001 |doi=10.1126/science.276.5317.1392}}</ref><ref>{{cite journal | last = Carbonell | first = Eudald | authorlink = Eudald Carbonell | coauthors = José M. Bermúdez de Castro ''et al.'' | title = The first hominin of Europe | journal = [[Nature (magazine)|Nature]] | volume = 452 | pages = 465–469 | date = 2008-03-27 | doi = 10.1038/nature06815 | accessdate = 2008-03-26 | url = http://www.nature.com/nature/journal/v452/n7186/full/nature06815.html}}</ref>
*''[[Homo cepranensis|H. cepranensis]]'' refers to a single skull cap from Italy, estimated to be about 800,000 years old.<ref>{{cite journal |author=Manzi G, Mallegni F, Ascenzi A |title=A cranium for the earliest Europeans: phylogenetic position of the hominid from Ceprano, Italy |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=98 |issue=17 |pages=10011–6 |year=2001 |pmid=11504953 |doi=10.1073/pnas.151259998 |pmc=55569}}</ref>

===''Heidelbergensis''===
''[[H. heidelbergensis]]'' ([[Heidelberg]] Man) lived from about 800,000 to about 300,000 years ago. Also proposed as ''Homo sapiens heidelbergensis'' or ''Homo sapiens paleohungaricus''.<ref>{{Cite journal
| doi = 10.1016/S0047-2484(03)00029-0
| title = Palaeopathological and variant conditions of the Homo heidelbergensis type specimen (Mauer, Germany)
| year = 2003
| author = Czarnetzki, A
| journal = Journal of Human Evolution
| volume = 44
| page = 479
}}</ref>

===''Rhodesiensis'', and the Gawis cranium===
*''H. rhodesiensis'', estimated to be 300,000–125,000 years old. Most current experts believe Rhodesian Man to be within the group of ''Homo heidelbergensis'' though other designations such as Archaic Homo sapiens and [[Homo sapiens rhodesiensis]] have also been proposed.
*In February 2006 a fossil, the [[Gawis cranium]], was found which might possibly be a species intermediate between ''H. erectus'' and ''H. sapiens'' or one of many evolutionary dead ends. The skull from Gawis, Ethiopia, is believed to be 500,000–250,000 years old. Only summary details are known, and no peer reviewed studies have been released by the finding team. Gawis man's facial features suggest its being either an intermediate species or an example of a "Bodo man" female.<ref>{{Cite press release| url=http://newsinfo.iu.edu/news/page/normal/3142.html| title=Scientists discover hominid cranium in Ethiopia| publisher=Indiana University|date=March 27, 2006| accessdate=2006-11-26}}</ref>

===''Neanderthalensis''===
''[[H. neanderthalensis]]'' lived from 400,000<ref>{{cite doi|10.1111/j.1469-185X.2008.00071.x}}</ref> years ago. Also proposed as ''Homo sapiens neanderthalensis'': there is ongoing debate over whether the '''Neanderthal Man''' was a separate species, ''Homo neanderthalensis'', or a subspecies of ''H. sapiens''.<ref>{{cite journal |author=Harvati K |title=The Neanderthal taxonomic position: models of intra- and inter-specific craniofacial variation |journal=J. Hum. Evol. |volume=44 |issue=1 |pages=107–32 |year=2003 |pmid=12604307 |doi=10.1016/S0047-2484(02)00208-7}}</ref> While the debate remains unsettled, evidence from sequencing [[mitochondrial DNA]] indicates that no significant gene flow occurred between ''H. neanderthalensis'' and ''H. sapiens'', and, therefore, the two were separate species that shared a common ancestor about 660,000 years ago.<ref>{{cite journal |author=Krings M, Stone A, Schmitz RW, Krainitzki H, Stoneking M, Pääbo S |title=Neandertal DNA sequences and the origin of modern humans |journal=Cell |volume=90 |issue=1 |pages=19–30 |year=1997 |pmid=9230299 |doi=10.1016/S0092-8674(00)80310-4}}</ref><ref>{{cite journal |author=Green RE, ''et al.'' |title=A Complete Neandertal Mitochondrial Genome Sequence Determined by High-Throughput Sequencing |journal=Cell |volume=134 |issue=3 |pages=416–426 |year=2008|doi=10.1016/j.cell.2008.06.021 |pmid=18692465 |pmc=2602844 }}</ref> In 1997, [[Mark Stoneking]] stated: "These results [based on mitochondrial DNA extracted from Neanderthal bone] indicate that Neanderthals did not contribute mitochondrial DNA to modern humans… Neanderthals are not our ancestors." Subsequent investigation of a second source of Neanderthal DNA supported these findings.<ref>{{cite journal |author=Serre D, Langaney A, Chech M, ''et al.'' |title=No evidence of Neandertal mtDNA contribution to early modern humans |journal=PLoS Biol. |volume=2 |issue=3 |page=E57 |year=2004 |pmid=15024415 |doi=10.1371/journal.pbio.0020057 |pmc=368159}}</ref> However, supporters of the multiregional hypothesis point to recent studies indicating non-African nuclear DNA heritage dating to one [[annum|Ma]],<ref>{{cite journal |author=Gutiérrez G, Sánchez D, Marín A |title=A reanalysis of the ancient mitochondrial DNA sequences recovered from Neandertal bones |journal=Mol. Biol. Evol. |volume=19 |issue=8 |pages=1359–66 |year=2002 |pmid=12140248 |doi=}}</ref> although the reliability of these studies has been questioned.<ref>{{cite journal |author=Hebsgaard MB, Wiuf C, Gilbert MT, Glenner H, Willerslev E |title=Evaluating Neanderthal genetics and phylogeny |journal=J. Mol. Evol. |volume=64 |issue=1 |pages=50–60 |year=2007 |pmid=17146600 |doi=10.1007/s00239-006-0017-y}}</ref> Competition from ''Homo sapiens'' probably contributed to Neanderthal extinction.<ref name="thirdchimp">{{Cite book
| last = Diamond
| first = Jared
| author-link = Jared Diamond
| title = The Third Chimpanzee: The Evolution and Future of the Human Animal
| publisher = Harper Perennial
| year = 1992
| isbn = 0060984031}}</ref><ref>[http://www.guardian.co.uk/science/2009/may/17/neanderthals-cannibalism-anthropological-sciences-journal How Neanderthals met a grisly fate: devoured by humans]. ''The Observer.'' May 17, 2009.</ref>

===''Sapiens''===
{{Main|Early Homo sapiens}}
''H. sapiens'' ('''"sapiens"''' is Latin for wise or intelligent) has lived from about 250,000 years ago to the present. Between 400,000 years ago and the second interglacial period in the Middle [[Pleistocene]], around 250,000 years ago, the trend in [[Cranial capacity|skull expansion]] and the elaboration of stone tool technologies developed, providing evidence for a transition from ''H. erectus'' to ''H. sapiens''. The direct evidence suggests there was a migration of ''H. erectus'' out of Africa, then a further [[speciation]] of ''H. sapiens'' from ''H. erectus'' in Africa. A subsequent migration within and out of Africa eventually replaced the earlier dispersed ''H. erectus''. This migration and origin theory is usually referred to as the ''recent single origin'' or [[Out of Africa theory]]. Current evidence does not preclude some multiregional evolution or some admixture of the migrant ''H. sapiens'' with existing ''Homo'' populations. This is a hotly debated area of [[paleoanthropology]].

Current research has established that human beings are genetically highly homogenous; that is, the DNA of individuals is more alike than usual for most species, which may have resulted from their relatively recent evolution or the possibility of a [[population bottleneck]] resulting from cataclysmic natural events such as the [[Toba catastrophe theory|Toba catastrophe]].<ref>[http://www.bbc.co.uk/science/horizon/1999/supervolcanoes_script.shtml Supervolcanoes], [[BBC2]], 3 February 2000</ref><ref name=ambrose1998>{{cite journal
| author=Stanley H. Ambrose
| title=Late Pleistocene human population bottlenecks, volcanic winter, and differentiation of modern humans
| journal=[[Journal of Human Evolution]] | year=1998 | volume=34 | issue=6 | pages= 623–651
| doi=10.1006/jhev.1998.0219
}}</ref><ref>{{cite web
| author=Ambrose, Stanley H. | year=2005
| title=Volcanic Winter, and Differentiation of Modern Humans | work=Bradshaw Foundation
| url=http://www.bradshawfoundation.com/evolution/ | accessdate=2006-04-08
}}</ref> Distinctive genetic characteristics have arisen, however, primarily as the result of small groups of people moving into new environmental circumstances. These adapted traits are a very small component of the ''Homo sapiens'' genome, but include various characteristics such as skin color and nose form, in addition to internal characteristics such as the ability to breathe more efficiently in high altitudes.

'''''[[Homo sapiens idaltu|H. sapiens idaltu]]''''', from Ethiopia, is a possible extinct sub-species who lived from about 160,000 years ago.

===''Floresiensis''===
{{Main|Homo floresiensis}}
''H. floresiensis'', which lived from approximately 100,000 to 12,000 before present, has been nicknamed ''[[hobbit]]'' for its small size, possibly a result of [[insular dwarfism]].<ref>{{cite journal |author=Brown P, Sutikna T, Morwood MJ, ''et al.'' |title=A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia |journal=Nature |volume=431 |issue=7012 |pages=1055–61 |year=2004 |pmid=15514638 |doi=10.1038/nature02999}}</ref> ''H. floresiensis'' is intriguing both for its size and its age, being a concrete example of a recent species of the genus ''Homo'' that exhibits derived traits not shared with modern humans. In other words, ''H. floresiensis'' share a common ancestor with modern humans, but split from the modern human lineage and followed a distinct evolutionary path. The main find was a skeleton believed to be a woman of about 30 years of age. Found in 2003 it has been dated to approximately 18,000 years old. The living woman was estimated to be one meter in height, with a brain volume of just 380&nbsp;cm<sup>3</sup> (considered small for a chimpanzee and less than a third of the ''H. sapiens'' average of 1400&nbsp;cm<sup>3</sup>).

However, there is an ongoing debate over whether ''H. floresiensis'' is indeed a separate species.<ref>{{cite journal |author=Argue D, Donlon D, Groves C, Wright R |title=Homo floresiensis: microcephalic, pygmoid, Australopithecus, or Homo? |journal=J. Hum. Evol. |volume=51 |issue=4 |pages=360–74 |year=2006 |pmid=16919706 |doi=10.1016/j.jhevol.2006.04.013}}</ref> Some scientists presently believe that ''H. floresiensis'' was a modern ''H. sapiens'' suffering from pathological dwarfism.<ref name=Martin>{{cite journal |author=Martin RD, Maclarnon AM, Phillips JL, Dobyns WB |title=Flores hominid: new species or microcephalic dwarf? |journal=The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology |volume=288 |issue=11 |pages=1123–45 |year=2006 |pmid=17031806 |doi=10.1002/ar.a.20389}}</ref> This hypothesis is supported in part, because some modern humans who live on [[Flores]], the island where the skeleton was found, are [[pygmies]]. This coupled with pathological dwarfism could indeed create a hobbit-like human. The other major attack on ''H. floresiensis'' is that it was found with tools only associated with ''H. sapiens''.<ref name=Martin/>

===Comparative table of ''Homo'' species===
{{homo}}

==Use of tools==
{{See also|Hunting hypothesis}}
Using tools has been interpreted as a sign of intelligence, and it has been theorized that tool use may have stimulated certain aspects of human evolution—most notably the continued expansion of the human brain. Paleontology has yet to explain the expansion of this organ over millions of years despite being extremely demanding in terms of energy consumption. The brain of a modern human consumes about 20 [[watt]]s (400 kilocalories per day), which is one fifth of the energy consumption of a human body. Increased tool use would allow hunting for energy-rich meat products, and would enable processing more energy-rich plant products. Researchers have suggested that early hominids were thus under evolutionary pressure to increase their capacity to create and use tools.<ref>{{cite journal |author=Gibbons, Ann |title=Solving the Brain's Energy Crisis |journal=Science |volume=280 |issue=5368 |pages=1345–47 |year=1998 |pmid=9634409 |doi=10.1126/science.280.5368.1345}}</ref>

Precisely when early humans started to use tools is difficult to determine, because the more primitive these tools are (for example, sharp-edged stones) the more difficult it is to decide whether they are natural objects or human artifacts. There is some evidence that the australopithecines (4 Ma) may have used broken bones as tools, but this is debated.
It should be noted that many species make and use tools, but it is the human species that dominates the areas of making and using more complex tools. A good question is, what species made and used the first tools? The oldest known tools are the "Oldowan stone tools" from Ethiopia. It was discovered that these tools are from 2.5 to 2.6 million years old, which predates the earliest known "Homo" species. There is no known evidence that any "Homo" specimens appeared by 2.5 Ma. A Homo fossil was found near some Oldowan tools, and its age was noted at 2.3 million years old, suggesting that maybe the Homo species did indeed create and use these tools. It is surely possible, but not solid evidence. Bernard Wood noted that "Paranthropus" coexisted with the early Homo species in the area of the "Oldowan Industrial Complex" over roughly the same span of time. Although there is no direct evidence that points to Paranthropus as the tool makers, their anatomy lends to indirect evidence of their capabilities in this area. Most paleoanthropologists agree that the early "Homo" species were indeed responsible for most of the Oldowan tools found. They argue that when most of the Oldowan tools were found in association with human fossils, Homo was always present, but Paranthropus was not.<ref name=Freeman>Freeman, Scott; Jon C. Herron. ''Evolutionary Analysis'' (4th ed.)., Pearson Education, Inc. (2007). ISBN 0-13-227584-8 pages 786-788</ref>

In 1994, Randall Susman used the anatomy of opposable thumbs as the basis for his argument that both the Homo and Paranthropus species were toolmakers. He compared bones and muscles of human and chimpanzee thumbs, finding that humans have 3 muscles that chimps lack. Humans also have thicker metacarpals with broader heads, making the human hand more successful at precision grasping than the chimpanzee hand. Susman defended that modern anatomy of the human thumb is an evolutionary response to the requirements associated with making and handling tools and that both species were indeed toolmakers.<ref name=Freeman/>

===Stone tools===
Stone tools are first attested around 2.6 Ma, when ''H. habilis'' in Eastern Africa used so-called [[pebble tools]], [[chopper (archaeology)|choppers]] made out of round pebbles that had been split by simple strikes.<ref name=Plummer>{{cite journal |author=Plummer T |title=Flaked stones and old bones: Biological and cultural evolution at the dawn of technology |journal=Am. J. Phys. Anthropol. |volume=Suppl 39 |issue= |pages=118–64 |year=2004 |pmid=15605391 |doi=10.1002/ajpa.20157}}</ref> This marks the beginning of the [[Paleolithic]], or Old Stone Age; its end is taken to be the end of the last Ice Age, around 10,000 years ago. The Paleolithic is subdivided into the [[Lower Paleolithic]] (Early Stone Age, ending around 350,000–300,000 years ago), the [[Middle Paleolithic]] (Middle Stone Age, until 50,000–30,000 years ago), and the [[Upper Paleolithic]].

The period from 700,000–300,000 years ago is also known as the [[Acheulean]], when ''H. ergaster'' (or ''erectus'') made large stone [[hand-axe]]s out of [[flint]] and [[quartzite]], at first quite rough (Early Acheulian), later "[[retouch]]ed" by additional, more subtle strikes at the sides of the [[lithic flake|flakes]]. After 350,000 BP ([[Before Present]]) the more refined so-called [[Levallois technique]] was developed. It consisted of a series of consecutive strikes, by which scrapers, slicers ("racloirs"), needles, and flattened needles were made.<ref name=Plummer/> Finally, after about 50,000 BP, ever more refined and specialized flint tools were made by the Neanderthals and the immigrant [[Cro-Magnon]]s (knives, blades, skimmers). In this period they also started to make tools out of bone.

===Modern humans and the "Great Leap Forward" debate===
{{See also|Behavioral modernity}}
Until about 50,000–40,000 years ago the use of stone tools seems to have progressed stepwise. Each phase (''H. habilis'', ''H. ergaster'', ''H. neanderthalensis'') started at a higher level than the previous one, but once that phase started further development was slow. These ''Homo'' species were culturally conservative, but after 50,000 BP modern human culture started to change at a much greater speed. [[Jared Diamond]], author of ''[[The Third Chimpanzee]]'', and some anthropologists characterize this as a "[[Behavioral modernity|Great Leap Forward]]."

Modern humans started burying their dead, making clothing out of hides, developing sophisticated hunting techniques (such as using [[trapping pit]]s or driving animals off cliffs), and engaging in [[cave painting]].<ref>{{cite journal |author=Ambrose SH |title=Paleolithic technology and human evolution |journal=Science |volume=291 |issue=5509 |pages=1748–53 |year=2001 |pmid=11249821 |doi=10.1126/science.1059487}}</ref> As human culture advanced, different populations of humans introduced novelty to existing technologies: artifacts such as fish hooks, buttons and bone needles show signs of variation among different populations of humans, something that had not been seen in human cultures prior to 50,000 BP. Typically, ''H. neanderthalensis'' populations do not vary in their technologies.

Among concrete examples of [[Modern human behavior]], anthropologists include specialization of tools, use of jewelery and images (such as cave drawings), organization of living space, rituals (for example, burials with grave gifts), specialized hunting techniques, exploration of less hospitable geographical areas, and [[barter]] trade networks. Debate continues as to whether a "revolution" led to modern humans ("the big bang of human consciousness"), or whether the evolution was more gradual.<ref>{{cite journal |author=Mcbrearty S, Brooks AS |title=The revolution that wasn't: a new interpretation of the origin of modern human behavior |journal=J. Hum. Evol. |volume=39 |issue=5 |pages=453–563 |year=2000 |pmid=11102266 |doi=10.1006/jhev.2000.0435}}</ref>

==Models of human evolution==
Today, all humans belong to one, undivided by species barrier, population of ''Homo sapiens sapiens''. However, according to the "Out of Africa" model this is not the first species of hominids: the first species of genus ''Homo'', ''Homo habilis'', evolved in East Africa at least 2 Ma, and members of this species populated different parts of Africa in a relatively short time. ''Homo erectus'' evolved more than 1.8 Ma, and by 1.5 Ma had spread throughout the [[Old World]].

Anthropologists have been divided as to whether current human population evolved as one interconnected population (as postulated by the [[Multiregional Evolution]] hypothesis), or evolved only in East Africa, [[speciation|speciated]], and then migrating out of Africa and replaced human populations in [[Eurasia]] (called the "Out of Africa" Model or the "Complete Replacement" Model).

===Multiregional model===
{{Main|Multiregional hypothesis}}
Multiregional evolution, a ''model to account for the pattern of human evolution'', was proposed by [[Milford H. Wolpoff]]<ref name=multiregional>{{cite journal
|last=Wolpoff
|first=MH
|coauthors=Hawks J, Caspari R
|date=2000
|title=Multiregional, not multiple origins
|journal=Am J Phys Anthropol
|volume=112
|issue=1
|pages=129–36
|url=http://www3.interscience.wiley.com/journal/71008905/abstract
|pdf=http://www.google.com/url?sa=t&source=web&ct=res&cd=1&url=http%3A%2F%2Fwww-personal.umich.edu%2F~wolpoff%2FPapers%2FMultiregional.PDF&ei=9HJ6SqPlBY-SNtWt5N0C&rct=j&q=%22Multiregional%2C+not+multiple+origins%22&usg=AFQjCNEhNgp4h_-LOZPqNuRV9_NbAB6zFg&sig2=dgiXnJ-cBkt42zlDb7hpdg
|doi=10.1002/(SICI)1096-8644(200005)112:1<129::AID-AJPA11>3.0.CO;2-K
|pmid=10766948}}</ref> in 1988.<ref name=Wolpoff1988>{{cite journal
| doi=10.1126/science.3136545
| last=Wolpoff
| first=MH
| coauthors=JN Spuhler, FH Smith, J Radovcic, G Pope, DW Frayer, R Eckhardt, and G Clark
| date=1988|title=Modern Human Origins
| journal=Science
| volume=241
| issue=4867
| pages=772–4
| url=http://www.sciencemag.org/cgi/pdf_extract/241/4867/772
| pmid=3136545
}}</ref> Multiregional evolution holds that human evolution from the beginning of the [[Pleistocene]] 2.5 million years [[Before Present|BP]] to the present day has been within a single, continuous [[human species]], evolving worldwide to modern ''Homo sapiens''.

According to the multiregional hypothesis, [[Multiregional evolution#Fossil evidence|fossil]] and genomic data are evidence for worldwide human evolution and contradict the recent speciation postulated by the Recent African origin hypothesis. The fossil evidence was insufficient for [[Richard Leakey]] to resolve this debate.<ref name=RLeakey>{{cite book|last=Leakey|first=Richard|title=The Origin of Humankind|publisher=Basic Books|location=New York, NY|year=1994|series=Science Masters Series|pages=87–89|isbn=0465053130}}</ref> Studies of [[haplogroup]]s in [[Human Y-chromosome DNA haplogroup|Y-chromosomal DNA]] and [[Human mitochondrial DNA haplogroup|mitochondrial DNA]] have largely supported a recent African origin.<ref>{{cite journal |author=Jorde LB, Bamshad M, Rogers AR |title=Using mitochondrial and nuclear DNA markers to reconstruct human evolution |journal=Bioessays |volume=20 |issue=2 |pages=126–36 |year=1998 |month=February |pmid=9631658 |doi=10.1002/(SICI)1521-1878(199802)20:2<126::AID-BIES5>3.0.CO;2-R}}</ref> Evidence from autosomal DNA also supports the Recent African origin. However the presence of [[Archaic Homo sapiens|archaic]] admixture in modern humans remains a possibility and has been suggested by some studies.<ref name="Wall, J. D. 2009 1823">{{Cite journal
| doi = 10.1093/molbev/msp096
| title = Detecting Ancient Admixture and Estimating Demographic Parameters in Multiple Human Populations
| year = 2009
| author = Wall, J. D.
| journal = Molecular Biology and Evolution
| volume = 26
| page = 1823
| last2 = Lohmueller
| first2 = K. E.
| last3 = Plagnol
| first3 = V.
}}</ref>

===Out of Africa===
{{See also|Recent single origin hypothesis|Early human migrations}}

According to the Out of Africa model, developed by [[Chris Stringer]] and Peter Andrews, modern ''H. sapiens'' evolved in Africa 200,000 years ago. ''Homo sapiens'' began migrating from Africa between 70,000 – 50,000 years ago and eventually replaced existing hominid species in Europe and Asia.<ref>[http://news.nationalgeographic.com/news/2007/07/070718-african-origin.html Modern Humans Came Out of Africa, "Definitive" Study Says]</ref><ref>{{cite journal |author=Stringer CB, Andrews P |title=Genetic and fossil evidence for the origin of modern humans |journal=Science |volume=239 |issue=4845 |pages=1263–8 |year=1988 |month=March |pmid=3125610 |doi=10.1126/science.3125610}}</ref> Out of Africa has gained support from research using mitochondrial DNA (mtDNA). After analysing genealogy trees constructed using 133 types of mtDNA, researchers concluded that all were descended from a woman from Africa, dubbed [[Mitochondrial Eve]]. Out of Africa is also supported by the fact that mitochondrial genetic diversity is highest among African populations.<ref name="Cann">{{cite journal |author=Cann RL, Stoneking M, Wilson AC |title=Mitochondrial DNA and human evolution |journal=Nature |volume=325 |issue=6099 |pages=31–6 |year=1987 |pmid=3025745 |doi=10.1038/325031a0 |url=http://artsci.wustl.edu/~landc/html/cann/}}</ref>

There are differing theories on whether there was a single exodus or several. A multiple dispersal model involves the Southern Dispersal theory,<ref name="lahr">[http://www.human-evol.cam.ac.uk/Projects/sdispersal/sdispersal.htm Searching for traces of the Southern Dispersal], by Dr. Marta Mirazón Lahr, et al.</ref> which has gained support in recent years from genetic, linguistic and archaeological evidence. In this theory, there was a coastal dispersal of modern humans from the [[Horn of Africa]] around 70,000 years ago. This group helped to populate Southeast Asia and Oceania, explaining the discovery of early human sites in these areas much earlier than those in the [[Levant]]. A second wave of humans dispersed across the [[Sinai peninsula]] into Asia, resulting in the bulk of human population for [[Eurasia]]. This second group possessed a more sophisticated tool technology and was less dependent on coastal food sources than the original group. Much of the evidence for the first group's expansion would have been destroyed by the rising sea levels at the end of the [[Holocene era]].<ref name="lahr"/> The multiple dispersal model is contradicted by studies indicating that the populations of Eurasia and the populations of Southeast Asia and Oceania are all descended from the same mitochondrial DNA lineages, which support a single migration out of Africa that gave rise to all non-African populations.<ref>{{cite journal
|title=Single, Rapid Coastal Settlement of Asia Revealed by Analysis of Complete Mitochondrial Genomes
|year=2005
|url=http://www.sciencemag.org/cgi/content/abstract/308/5724/1034
|doi=10.1126/science.1109792
|author=Macaulay, V.
|journal=Science
|volume=308
|page=1034
|pmid=15890885
|last2=Hill
|first2=C
|last3=Achilli
|first3=A
|last4=Rengo
|first4=C
|last5=Clarke
|first5=D
|last6=Meehan
|first6=W
|last7=Blackburn
|first7=J
|last8=Semino
|first8=O
|last9=Scozzari
|first9=R
|issue=5724
}}</ref>

The broad study of African genetic diversity headed by Dr.Sarah Tishkoff found the [[Bushmen|San people]] to express the greatest genetic diversity among the 113 distinct populations sampled, making them one of 14 "[[ancestral population clusters]]". The research also located the origin of modern human migration in south-western Africa, near the coastal border of [[Namibia]] and [[Angola]].<ref>[http://news.bbc.co.uk/2/hi/science/nature/8027269.stm BBC World News "Africa's genetic secrets unlocked"], 1 May 2009; the results were published in the online edition of the journal ''Science''.</ref>

== Contemporary Human Evolution ==

Natural selection is being observed in contemporary human populations, with recent findings demonstrating the population which is at risk of the severe debilitating disease [[kuru (disease)|kuru]] has significant over representation of an immune variant of the [[prion protein]] gene G127V versus non immune alleles. Scientists postulate one of the reasons for the rapid selection of this [[genetic variant]] is the lethality of the disease in non-immune persons.<ref>{{Cite news| last = Medical Research Council (UK)| first = | coauthors = | title = Brain Disease 'Resistance Gene' Evolves in Papua New Guinea Community; Could Offer Insights Into CJD| newspaper = Science Daily (online)| location = Science News| pages = | language = | publisher =| date = (November 21, 2009)| url = http://www.sciencedaily.com/releases/2009/11/091120091959.htm| accessdate = 2009-11-22}}</ref><ref>{{cite doi|10.1056/NEJMoa0809716}}</ref> Other reported evolutionary trends in other populations include a lengthening of the reproductive period, reduction in cholesterol levels, blood glucose and blood pressure.<ref>{{cite doi|10.1073/pnas.0906199106}}</ref>

==Genetics==
{{Main|Human evolutionary genetics}}
Human evolutionary genetics studies how one [[human genome]] differs from the other, the evolutionary past that gave rise to it, and its current effects. Differences between genomes have [[anthropological]], [[medical]] and [[forensic]] implications and applications. Genetic data can provide important insight into human evolution.

==Notable human evolution researchers==
{{See also|:Category:Human evolution theorists}}
*[[Robert Broom]], a Scottish physician and [[palaeontologist]] whose work on [[South Africa]] led to the discovery and description of the [[Paranthropus]] genus of hominins, and of "[[Mrs. Ples]]"
*[[James Burnett, Lord Monboddo]], a British judge most famous today as a founder of modern comparative historical linguistics
*[[Raymond Dart]], an Australian anatomist and [[palaeoanthropologist]], whose work at Taung, in South Africa, led to the discovery of ''Australopithecus africanus''
*[[Charles Darwin]], a British naturalist who documented considerable evidence that species originate through evolutionary change
*[[Richard Dawkins]], a British ethologist, evolutionary biologist who has promoted a [[gene-centered view of evolution]]
*[[J. B. S. Haldane]], a British geneticist and evolutionary biologist
*[[William D. Hamilton]], a British Evolutionary Biologist who expounded a rigorous genetic basis for [[kin selection]], and on the evolution of [[HIV]] and other human diseases.
*[[Sir Alister Hardy]], a British zoologist, who first hypothesised the [[aquatic ape theory]] of human evolution
*[[Henry McHenry]], an American anthropologist who specializes in studies of human evolution, the origins of bipedality, and paleoanthropology
*[[Louis Leakey]], an African archaeologist and naturalist whose work was important in establishing human evolutionary development in Africa
*[[Mary Leakey]], a British archaeologist and anthropologist whose discoveries in Africa include the [[Laetoli footprints]]
*[[Richard Leakey]], an African paleontologist and archaeologist, son of Louis and Mary Leakey
*[[Svante Pääbo]], a Swedish biologist specializing in evolutionary genetics
*[[Jeffrey H. Schwartz]], an American physical anthropologist and professor of biological anthropology
*[[Chris Stringer]], anthropologist, leading proponent of the recent single origin hypothesis
*[[Alan Templeton]], geneticist and statistician, proponent of the multiregional hypothesis
*[[Philip V. Tobias]], a South African palaeoanthropologist is one of the world's leading authorities on the evolution of humankind
*[[Erik Trinkaus]], a prominent American paleoanthropologist and expert on Neanderthal biology and human evolution
*[[Alfred Russel Wallace]], a British naturalist, sometimes called the "father of [[biogeography]]", who independently from Charles Darwin proposed the principles of evolution of animal species
*[[Milford H. Wolpoff]], an American paleoanthropologist who is the leading proponent of the multiregional evolution hypothesis.

==Species list==
This list is in chronological order across the page by [[genus]].
{{Multicol}}
*''Sahelanthropus''
**''[[Sahelanthropus tchadensis]]''
*''Orrorin''
**''[[Orrorin tugenensis]]''
*''[[Ardipithecus]]''
**''Ardipithecus kadabba''
**''Ardipithecus ramidus''
{{Multicol-break}}
*''[[Australopithecus]]''
**''[[Australopithecus anamensis]]''
**''[[Australopithecus afarensis]]''
**''[[Australopithecus bahrelghazali]]''
**''[[Australopithecus africanus]]''
**''[[Australopithecus garhi]]''
*''[[Paranthropus]]''
**''[[Paranthropus aethiopicus]]''
**''[[Paranthropus boisei]]''
**''[[Paranthropus robustus]]''
*''Kenyanthropus''
**''[[Kenyanthropus platyops]]''
{{Multicol-break}}
*''[[Homo (genus)|Homo]]''
**''[[Homo habilis]]''
**''[[Homo rudolfensis]]''
**''[[Homo ergaster]]''
**''[[Homo georgicus]]''
**''[[Homo erectus]]''
**''[[Homo cepranensis]]''
**''[[Homo antecessor]]''
**''[[Homo heidelbergensis]]''
**''[[Homo rhodesiensis]]''
**''[[Neanderthal|Homo neanderthalensis]]''
**''[[Homo sapiens idaltu]]''
**''Homo sapiens'' ([[Cro-Magnon]])
**''[[Human|Homo sapiens sapiens]]''
**''[[Homo floresiensis]]''
{{Multicol-end}}

== See also ==
{{Col-begin}}
{{Col-break|width=45%}}
* [[List of human evolution fossils]]
* [[Timeline of human evolution]]
* [[Archaeogenetics]]
* [[Dual inheritance theory]]
* [[Dysgenics]]
* [[Evolutionary anthropology]]
* [[Evolutionary medicine]]
* [[Evolutionary neuroscience]]
* [[Evolution of human intelligence]]
* [[Evolution of morality]]
* [[Evolutionary origin of religions]]
{{Col-break|gap=3em}}
{{Portal|Evolutionary biology|Tree_of_life.svg}}
* [[Evolutionary psychology]]
* [[History of Earth]]
* [[Hominid intelligence]]
* [[Human behavioral ecology]]
* [[Human skeletal changes due to bipedalism]]
* [[Human vestigiality]]
* [[Ida (fossil)]]
* [[Physical anthropology]]
* [[Sahara pump theory]]
* [[Sexual selection in human evolution]]
* [[Sociocultural evolution]]
{{Col-end}}

==References==
===Notes===
{{reflist|2}}

=== Further reading ===
{{Main|Bibliography of evolution and human behavior}}

* {{cite journal|last=Alexander|first=R. D.|date=1990|title=How Did Humans Evolve? Reflections on the Uniquely Unique Species|journal=University of Michigan Museum of Zoology Special Publication|publisher=University of Michigan Museum of Zoology|issue=1|pages=1–38|url=http://insects.ummz.lsa.umich.edu/pdfs/Alexander1990.pdf}}
* Flinn, M. V., Geary, D. C., & Ward, C. V. (2005). Ecological dominance, social competition, and coalitionary arms races: Why humans evolved extraordinary intelligence. ''Evolution and Human Behavior, 26,'' 10-46. {{PDFlink|[http://web.missouri.edu/~gearyd/Flinnetal2005.pdf Full text.]|345&nbsp;KB}}
*{{cite book|title= The Cambridge Encyclopedia of Human Evolution | editors=Jones, S., Martin, R., & Pilbeam, D. | year=1994 | publisher= Cambridge University Press | location =Cambridge |isbn=0-521-32370-3|author= edited by Steve Jones, Robert Martin, and David Pilbeam ; foreword by Richard Dawkins.}} Also ISBN 0-521-46786-1
* {{cite journal
| author = Wolfgang Enard et al.
| title = Molecular evolution of [[FOXP2]], a gene involved in speech and language
| journal = Nature
| volume = 418
|date= 2002-08-22
| page = 870
}}
* [http://www.psu.edu/ur/NEWS/news/Neandertal.html DNA Shows Neandertals Were Not Our Ancestors]
* {{cite journal
| author = J. W. IJdo, A. Baldini, D. C. Ward, S. T. Reeders, R. A. Wells
| title = Origin of human chromosome 2: An ancestral telomere-telomere fusion
| journal = Genetics
| volume = 88
| pages = 9051–9055
| month = October
| format= PDF
| year = 1991
| url = http://www.pnas.org/cgi/reprint/88/20/9051.pdf
}}—two ancestral ape chromosomes fused to give rise to human chromosome 2.
* {{cite journal
| author = Ovchinnikov, et al.
| title = Molecular analysis of Neanderthal DNA from the Northern [[Caucasus]]
| journal = Nature
| volume = 404
| page = 490
| year = 2000
| doi = 10.1038/35006625
| last2 = Götherström
| first2 = Anders
| last3 = Romanova
| first3 = Galina P.
| last4 = Kharitonov
| first4 = Vitaliy M.
| last5 = Lidén
| first5 = Kerstin
| last6 = Goodwin
| first6 = William
}}
* {{cite journal
| author = Heizmann, Elmar P J, Begun, David R
| title = The oldest Eurasian hominoid
| journal = [[Journal of Human Evolution]]
| volume = 41
| issue = 5
| year = 2001
| doi = 10.1006/jhev.2001.0495
| page = 463
}}
* [http://news.bbc.co.uk/2/hi/science/nature/6937476.stm BBC: Finds test human origins theory.] 2007-08-08 ''Homo habilis'' and ''Homo erectus'' are sister species that overlapped in time.

== External links ==
{{commonscat}}
* [http://www.bbc.co.uk/sn/prehistoric_life/human/human_evolution/index.shtml BBC: The Evolution of Man]
* [http://www.evolution-textbook.org/content/free/figures/ch25.html Illustrations from ''Evolution'' (textbook)]
* [http://www.mnh.si.edu/anthro/humanorigins/ha/sap.htm Smithsonian – Homosapiens]
* [http://www.mnh.si.edu/anthro/humanorigins/faq/encarta/encarta.htm Smithsonian – The Human Origins Program]
* [http://www.becominghuman.org Becoming Human: Paleoanthropology, Evolution and Human Origins, presented by Arizona State University's Institute of Human Origins]

{{Human Evolution}}
{{Evolutionary biology}}
{{Human}}
{{Apes}}

{{DEFAULTSORT:Human Evolution}}
[[Category:Human evolution| ]]
[[Category:Neogene]]
[[Category:Recent single origin hypothesis]]
[[Category:Sociocultural evolution]]
[[Category:Anthropology]]

[[ar:تطور الإنسان]]
[[bn:মানব বিবর্তন]]
[[bs:Ljudska evolucija]]
[[bg:Еволюция на човека]]
[[ca:Evolució humana]]
[[cs:Vývoj člověka]]
[[da:Menneskets udvikling]]
[[de:Stammesgeschichte des Menschen]]
[[et:Inimese evolutsioon]]
[[el:Ανθρώπινη εξέλιξη]]
[[es:Evolución humana]]
[[eu:Giza eboluzioa]]
[[fa:تکامل انسان]]
[[fr:Histoire évolutive des homininés]]
[[gl:Evolución humana]]
[[ko:인류의 진화]]
[[hi:मानव का विकास]]
[[hr:Evolucija čovjeka]]
[[io:Evoluciono di homo]]
[[id:Evolusi manusia]]
[[is:Þróun mannsins]]
[[it:Evoluzione umana]]
[[kn:ಮಾನವನ ವಿಕಾಸ]]
[[la:Evolutio hominis]]
[[lt:Žmogaus evoliucija]]
[[hu:Emberré válás]]
[[mk:Еволуција на човекот]]
[[nl:Evolutie van de mens]]
[[ja:人類の進化]]
[[no:Menneskets evolusjon]]
[[nov:Homal evolutione]]
[[pl:Antropogeneza]]
[[pt:Evolução humana]]
[[ro:Antropogeneză]]
[[ru:Антропогенез]]
[[scn:Evuluzzioni umana]]
[[simple:Human evolution]]
[[sk:Antropogenéza]]
[[sl:Nastanek in razvoj človeka]]
[[sr:Развој човека]]
[[sh:Ljudska evolucija]]
[[fi:Ihmisen evoluutio]]
[[sv:Människans utveckling]]
[[th:วิวัฒนาการของมนุษย์]]
[[tr:İnsan türünün evrimi]]
[[uk:Антропогенез]]
[[fiu-vro:Inemise evoluts'uun]]
[[vls:Evoluusje van den miens]]
[[war:Ebolusyon han tawo]]
[[zh:人類演化]]

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