Early modern human: Difference between revisions

Page semi-protected
From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
Dbachmann (talk | contribs)
227,714 edits
Dbachmann (talk | contribs)
227,714 edits
→‎Dispersal and archaic admixture: reducing content duplication / redundancy within section
Line 60: Line 60:
Dispersal of early ''H. sapiens'' begins soon after its emergence.
Dispersal of early ''H. sapiens'' begins soon after its emergence.


The [[Khoi-San]] of Southern Africa may be the human population with the deepest temporal division from all other contemporary populations, estimated at close to 130,000 years ago. A 2011 study has classified them as an "ancestral population cluster". The same study also located the origin of the first wave of expansion of ''H. sapiens'', beginning roughly [[Recent African origin of modern humans#Early northern Africa dispersal|130,000 years ago]], in southwestern Africa, near the coastal border of [[Namibia]] and [[Angola]].<ref>{{cite journal |last1=Henn |first1=Brenna |last2=Gignoux |first2=Christopher R. |last3=Jobin |first3=Matthew |year=2011 |title=Hunter-gatherer genomic diversity suggests a southern African origin for modern humans |journal=[[Proceedings of the National Academy of Sciences of the United States of America]] |volume=108 |issue=13 |pages=5154–62 |publisher=[[National Academy of Sciences]] |doi=10.1073/pnas.1017511108 |bibcode=2011PNAS..108.5154H |pmid=21383195 |pmc=3069156}}</ref> A 2017 analysis suggested that the Khoi-San diverged from West African populations even earlier, between 260,000 and 350,000 years ago, compatible with (an upper limit of) the age of ''H. sapiens''.<ref>{{cite journal |last=Schlebusch |display-authors=etal |title=Southern African ancient genomes estimate modern human divergence to 350,000 to 260,000 years ago |journal=Science |volume=358 |issue=6363 |date=3 November 2017 |pages=652&ndash;655 |doi=10.1126/science.aao6266}}</ref>
The [[Khoi-San]] of Southern Africa may be the human population with the deepest temporal division from all other contemporary populations, estimated at close to 130,000 years ago. A 2011 study has classified them as an "ancestral population cluster". The same study also located the origin of the first wave of expansion of ''H. sapiens'', beginning roughly [[Recent African origin of modern humans#Early northern Africa dispersal|130,000 years ago]], in southwestern Africa, near the coastal border of [[Namibia]] and [[Angola]].<ref>{{cite journal |last1=Henn |first1=Brenna |last2=Gignoux |first2=Christopher R. |last3=Jobin |first3=Matthew |year=2011 |title=Hunter-gatherer genomic diversity suggests a southern African origin for modern humans |journal=[[Proceedings of the National Academy of Sciences of the United States of America]] |volume=108 |issue=13 |pages=5154–62 |publisher=[[National Academy of Sciences]] |doi=10.1073/pnas.1017511108 |bibcode=2011PNAS..108.5154H |pmid=21383195 |pmc=3069156}}</ref> A 2017 analysis suggested that the Khoi-San diverged from West African populations even earlier, between 260,000 and 350,000 years ago, compatible with (an upper limit of) the age of ''H. sapiens''.<ref>{{cite journal |last=Schlebusch |display-authors=etal |title=Southern African ancient genomes estimate modern human divergence to 350,000 to 260,000 years ago |journal=Science |volume=358 |issue=6363 |date=3 November 2017 |pages=652&ndash;655 |doi=10.1126/science.aao6266}}</ref> ''[[Homo sapiens idaltu]]'', found at site [[Middle Awash]] in Ethiopia, lived about 160,000 years ago.<ref>{{cite journal |last1=White |first1=Tim D. |last2=Asfaw |first2=Berhane |last3=Degusta |first3=David |last4=Gilbert |first4=Henry |last5=Richards |first5=Gary D. |last6=Suwa |first6=Gen |last7=Howell |first7=Clark F. |date=June 2003 |title=Pleistocene ''Homo sapiens'' from Middle Awash, Ethiopia |journal=Nature |volume=423 |issue=6941 |pp= 742–7 |pmid=12802332 |doi=10.1038/nature01669 |bibcode=2003Natur.423..742W }}</ref>
The discovery of fossils attributed to ''H. sapiens,'' along with stone tools, dated to approximately 300,000 years ago, found at [[Jebel Irhoud]], Morocco was announced in 2017.<ref name="NAT-20170607a">{{cite journal |last=Callaway |first=Ewan |title=Oldest Homo sapiens fossil claim rewrites our species' history |url=http://www.nature.com/news/oldest-homo-sapiens-fossil-claim-rewrites-our-species-history-1.22114 |date=7 June 2017 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature.2017.22114 |accessdate=11 June 2017 }}</ref>
The discovery of fossils attributed to ''H. sapiens,'' along with stone tools, dated to approximately 300,000 years ago, found at [[Jebel Irhoud]], Morocco was announced in 2017.<ref name="NAT-20170607a">{{cite journal |last=Callaway |first=Ewan |title=Oldest Homo sapiens fossil claim rewrites our species' history |url=http://www.nature.com/news/oldest-homo-sapiens-fossil-claim-rewrites-our-species-history-1.22114 |date=7 June 2017 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature.2017.22114 |accessdate=11 June 2017 }}</ref>

''[[Homo sapiens idaltu]]'', found at site [[Middle Awash]] in Ethiopia, lived about 160,000 years ago.<ref>{{cite journal |last1=White |first1=Tim D. |last2=Asfaw |first2=Berhane |last3=Degusta |first3=David |last4=Gilbert |first4=Henry |last5=Richards |first5=Gary D. |last6=Suwa |first6=Gen |last7=Howell |first7=Clark F. |date=June 2003 |title=Pleistocene ''Homo sapiens'' from Middle Awash, Ethiopia |journal=Nature |volume=423 |issue=6941 |pp= 742–7 |pmid=12802332 |doi=10.1038/nature01669 |bibcode=2003Natur.423..742W }}</ref><ref name="NatGeo 2005">{{cite web|last1=Mayell|first1=Hillary|title=Oldest Human Fossils Identified|url=http://news.nationalgeographic.com/news/2005/02/0216_050216_omo.html|journal=National Geographic|date=16 February 2005|accessdate=1 October 2017}}</ref>


Early ''H. sapiens'' may have reached Asia in a first wave as early as 120,000 years ago.<ref name="SCI-20171208">{{cite journal |last1=Bae |first1=Christopher J. |last2=Douka |first2=Katerina |last3=Petraglia |first3=Michael D. |title=On the origin of modern humans: Asian perspectives |url=http://science.sciencemag.org/content/358/6368/eaai9067 |journal=[[Science (journal)|Science]] |date=8 December 2017 |volume=358 |issue=6368 |page=eaai9067 |doi=10.1126/science.aai9067 |accessdate=10 December 2017 }}</ref><ref name="QZ-20171210">{{cite web |last=Kuo |first=Lily |title=Early humans migrated out of Africa much earlier than we thought |url=https://qz.com/1151816/early-humans-migrated-out-of-africa-much-earlier-than-we-thought/ |date=10 December 2017 |work=[[Quartz (publication)|Quartz]] |accessdate=10 December 2017 }}</ref><ref>{{cite news|url=http://www.ibtimes.co.in/177000-year-old-jawbone-fossil-discovered-israel-oldest-human-remains-found-outside-africa-758401|title=A 177,000-year-old jawbone fossil discovered in Israel is oldest human remains found outside Africa|author=Ankita Mehta|date=26 January 2018|publisher=International Business Times}}</ref>
Early ''H. sapiens'' may have reached Asia in a first wave as early as 120,000 years ago.<ref name="SCI-20171208">{{cite journal |last1=Bae |first1=Christopher J. |last2=Douka |first2=Katerina |last3=Petraglia |first3=Michael D. |title=On the origin of modern humans: Asian perspectives |url=http://science.sciencemag.org/content/358/6368/eaai9067 |journal=[[Science (journal)|Science]] |date=8 December 2017 |volume=358 |issue=6368 |page=eaai9067 |doi=10.1126/science.aai9067 |accessdate=10 December 2017 }}</ref><ref name="QZ-20171210">{{cite web |last=Kuo |first=Lily |title=Early humans migrated out of Africa much earlier than we thought |url=https://qz.com/1151816/early-humans-migrated-out-of-africa-much-earlier-than-we-thought/ |date=10 December 2017 |work=[[Quartz (publication)|Quartz]] |accessdate=10 December 2017 }}</ref><ref>{{cite news|url=http://www.ibtimes.co.in/177000-year-old-jawbone-fossil-discovered-israel-oldest-human-remains-found-outside-africa-758401|title=A 177,000-year-old jawbone fossil discovered in Israel is oldest human remains found outside Africa|author=Ankita Mehta|date=26 January 2018|publisher=International Business Times}}</ref>
Line 69: Line 67:


The [[Recent African origin of modern humans|Recent "Out of Africa" migration]] of ''Homo sapiens'' took place in at least two waves, the first around 130,000 to 100,000 years ago, the second ([[Southern Dispersal]]) around 70,000 to 60,000 years ago.
The [[Recent African origin of modern humans|Recent "Out of Africa" migration]] of ''Homo sapiens'' took place in at least two waves, the first around 130,000 to 100,000 years ago, the second ([[Southern Dispersal]]) around 70,000 to 60,000 years ago.
⚫
Evidence for the overwhelming contribution of the "recent African origin" of modern populations outside of Africa was established based on [[mitochondrial DNA]], combined with evidence based on [[physical anthropology]] of archaic [[Biological specimen|specimens]], during the 1990s and 2000s.</ref>{{cite journal | last1 = Liu | first1 = Hua | display-authors = etal | year = 2006 | title = A Geographically Explicit Genetic Model of Worldwide Human-Settlement History | doi = 10.1086/505436 | journal = The American Journal of Human Genetics | volume = 79 | issue = 2| pages = 230–237 | quote = Currently available genetic and archaeological evidence is generally interpreted as supportive of a recent single origin of modern humans in East Africa. | pmid=16826514 | pmc=1559480}}
Eurasia had long been populated by [[archaic humans]], due to the "[[Out of Africa I]]" migration more than a million years before.
⚫
{{cite journal|url=http://www.sciencemag.org/cgi/content/summary/sci;308/5724/921g |title=Out of Africa Revisited |doi=10.1126/science.308.5724.921g |date=2005-05-13 |accessdate=2009-11-23 |volume=308 |issue=5724 |journal=Science |page=921g}}</ref>

Since the 2010s, [[archaic human admixture with modern humans|admixture events]] ([[introgression]]) of populations of ''H. sapiens'' with populations of archaic humans have been discovered as having taken place between roughly 100,000 and 30,000 years ago, both in Eurasia and in Sub-Saharan Africa.
The assumption of complete replacement has been revised in the 2010s with the discovery [[archaic human admixture with modern humans|admixture events]] ([[introgression]]) of populations of ''H. sapiens'' with populations of archaic humans have been discovered as having taken place between roughly 100,000 and 30,000 years ago, both in Eurasia and in Sub-Saharan Africa.
The level of [[Neanderthal admixture]] varies significantly among contemporary racial groups, being absent in Africans, intermediate in Europeans and highest in East Asians. Certain genes related to UV-light adaptation introgressed from Neanderthals have been found to have been selected for in East Asians specifically from 45,000 years ago until around 5,000 years ago.<ref name=dinch3>{{cite journal| last=Ding|first=Q.|author2=Hu, Y.|author3= Xu, S.|author4= Wang, J.|author5= Jin, L.| title=Neanderthal Introgression at Chromosome 3p21.31 was Under Positive Natural Selection in East Asians| journal=Molecular Biology and Evolution| year=2014| origyear=Online 2013 | volume=31 |issue=3 |pages=683–695| doi=10.1093/molbev/mst260 | pmid=24336922}}</ref> Cumulatively, about 20% of the Neanderthal genome is estimated to remain present in contemporary populations.<ref name=vern14res>{{cite journal| last=Vernot| first=B.|author2=Akey, J. M.| title=Resurrecting Surviving Neandertal Lineages from Modern Human Genomes| journal=Science| date=2014| volume=343 |issue=6174 |pages=1017–1021| doi=10.1126/science.1245938| pmid=24476670|bibcode=2014Sci...343.1017V}}</ref>
The extent of [[Neanderthal admixture]] (and [[introgression]] of genes acquired by admixture) varies significantly between contemporary racial groups, being absent in Africans, intermediate in Europeans and highest in East Asians. Certain genes related to UV-light adaptation introgressed from Neanderthals have been found to have been selected for in East Asians specifically from 45,000 years ago until around 5,000 years ago.<ref name=dinch3>{{cite journal| last=Ding|first=Q.|author2=Hu, Y.|author3= Xu, S.|author4= Wang, J.|author5= Jin, L.| title=Neanderthal Introgression at Chromosome 3p21.31 was Under Positive Natural Selection in East Asians| journal=Molecular Biology and Evolution| year=2014| origyear=Online 2013 | volume=31 |issue=3 |pages=683–695| doi=10.1093/molbev/mst260 | pmid=24336922}}</ref> Cumulatively, about 20% of the Neanderthal genome is estimated to remain present in contemporary populations.<ref name=vern14res>{{cite journal| last=Vernot| first=B.|author2=Akey, J. M.| title=Resurrecting Surviving Neandertal Lineages from Modern Human Genomes| journal=Science| date=2014| volume=343 |issue=6174 |pages=1017–1021| doi=10.1126/science.1245938| pmid=24476670|bibcode=2014Sci...343.1017V}}</ref>
⚫
The extent of archaic admixture is of the order of about 1% to 4% in Europeans and East Asians, and highest among [[Melanesians]] ([[Denisova hominin]] admixture), at 4% to 6%.<ref>{{cite journal |url=http://www.sciencemag.org/cgi/content/full/328/5979/710 |title=A Draft Sequence of the Neandertal Genome |year=2010 |last=Green |first1=RE | display-authors = etal|last2=Krause |first2=J |last3=Briggs |first3=AW |last4=Maricic |first4=T |last5=Stenzel |first5=U |last6=Kircher |first6=M |last7=Patterson |first7=N |last8=Li |first8=H |last9=Zhai |first9=W |last10=Fritz |first10=M. H. Y. |last11=Hansen |first11=N. F. |last12=Durand |first12=E. Y. |last13=Malaspinas |first13=A. S. |last14=Jensen |first14=J. D. |last15=Marques-Bonet |first15=T. |last16=Alkan |first16=C. |last17=Prufer |first17=K. |last18=Meyer |first18=M. |last19=Burbano |first19=H. A. |last20=Good |first20=J. M. |last21=Schultz |first21=R. |last22=Aximu-Petri |first22=A. |last23=Butthof |first23=A. |last24=Hober |first24=B. |last25=Hoffner |first25=B. |last26=Siegemund |first26=M. |last27=Weihmann |first27=A. |last28=Nusbaum |first28=C. |last29=Lander |first29=E. S. |last30=Russ |first30=C. |volume=328 |issue=5979 |pages=710–22 |journal=Science |doi=10.1126/science.1188021|pmid=20448178 |pmc=5100745 |ref=harv|bibcode=2010Sci...328..710G }}.

{{cite journal | last=Reich | first=D. |author2=Green, R.E. |author3=Kircher, M. |author4=Krause, J. |author5=Patterson, N. |author6=Durand, E.Y. | title=Genetic history of an archaic hominin group from Denisova Cave in Siberia | journal=Nature | year=2010 | volume=468 | issue=7327 | pages=1053–1060 | doi=10.1038/nature09710 | pmid=21179161|display-authors=etal|bibcode=2010Natur.468.1053R | pmc=4306417}}.
The recent dispersal of ''H. sapiens'' from Africa (known as the ''recent single-origin hypothesis'' or ''Recent African Origin'' model) had been speculative until the 1980s, and competed with the so-called [[Multiregional origin of modern humans|multiregional origin model]].
</ref>
Evidence for the overwhelming contribution of the "recent African origin" of modern populations outside of Africa, due to the wave of expansion beginning after 70,000 years ago, was established based on [[mitochondrial DNA]], combined with evidence based on [[physical anthropology]] of archaic [[Biological specimen|specimens]], during the 1990s and 2000s.
⚫
The assumption of complete replacement has been revised in the 2010s with the discovery of limited admixture (of the order of a few percent).<ref>Green et al. (2010) suggest that their findings are consistent with Neanderthal admixture of up to 4% in some populations. But the study also suggests that there may be other reasons why humans and Neanderthals share ancient genetic lineages. {{cite journal |url=http://www.sciencemag.org/cgi/content/full/328/5979/710 |title=A Draft Sequence of the Neandertal Genome |year=2010 |last=Green |first1=RE | display-authors = etal|last2=Krause |first2=J |last3=Briggs |first3=AW |last4=Maricic |first4=T |last5=Stenzel |first5=U |last6=Kircher |first6=M |last7=Patterson |first7=N |last8=Li |first8=H |last9=Zhai |first9=W |last10=Fritz |first10=M. H. Y. |last11=Hansen |first11=N. F. |last12=Durand |first12=E. Y. |last13=Malaspinas |first13=A. S. |last14=Jensen |first14=J. D. |last15=Marques-Bonet |first15=T. |last16=Alkan |first16=C. |last17=Prufer |first17=K. |last18=Meyer |first18=M. |last19=Burbano |first19=H. A. |last20=Good |first20=J. M. |last21=Schultz |first21=R. |last22=Aximu-Petri |first22=A. |last23=Butthof |first23=A. |last24=Hober |first24=B. |last25=Hoffner |first25=B. |last26=Siegemund |first26=M. |last27=Weihmann |first27=A. |last28=Nusbaum |first28=C. |last29=Lander |first29=E. S. |last30=Russ |first30=C. |volume=328 |issue=5979 |pages=710–22 |journal=Science |doi=10.1126/science.1188021|pmid=20448178 |pmc=5100745 |ref=harv|bibcode=2010Sci...328..710G }}. Eriksson and Manica (2012)
proposed that the DNA overlap is a remnant of a common ancestor of both Neanderthals and modern humans. Anders Eriksson and Andrea Manica
[http://www.pnas.org/content/early/2012/08/14/1200567109 Effect of ancient population structure on the degree of polymorphism shared between modern human populations and ancient hominins] PNAS 2012 : 1200567109v1-201200567. July 20, 2012</ref>

⚫
The recent single origin of modern humans in [[East Africa]] was the near-consensus position held within the scientific community prior to 2010.<ref>{{cite journal | last1 = Liu | first1 = Hua | display-authors = etal | year = 2006 | title = A Geographically Explicit Genetic Model of Worldwide Human-Settlement History | doi = 10.1086/505436 | journal = The American Journal of Human Genetics | volume = 79 | issue = 2| pages = 230–237 | quote = Currently available genetic and archaeological evidence is generally interpreted as supportive of a recent single origin of modern humans in East Africa. However, this is where '''the near consensus''' on human settlement history ends, and considerable uncertainty clouds any more detailed aspect of human colonization history. | pmid=16826514 | pmc=1559480}}
⚫
{{cite journal|url=http://www.sciencemag.org/cgi/content/summary/sci;308/5724/921g |title=Out of Africa Revisited |doi=10.1126/science.308.5724.921g |date=2005-05-13 |accessdate=2009-11-23 |volume=308 |issue=5724 |journal=Science |page=921g}}
{{cite journal|author=Nature |url=http://www.nature.com/nature/journal/v423/n6941/full/423692a.html |title=Human evolution: Out of Ethiopia |journal=Nature |date=2003-06-12 |accessdate=2009-11-23 |volume=423 |issue=6941|doi=10.1038/423692a |pages=692–695 |pmid=12802315|bibcode=2003Natur.423..692S }}
{{cite web|url=http://www.actionbioscience.org/evolution/johanson.html |title=Origins of Modern Humans: Multiregional or Out of Africa? |publisher=ActionBioscience |accessdate=2009-11-23}}
{{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 |accessdate=2009-11-23}}</ref>
The multiregional origin model, proposed by [[Milford H. Wolpoff]]<ref name=multiregional>{{cite journal
| author=Wolpoff, MH
| author2=Hawks, J
| author2-link=John D. Hawks
| author3=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
| 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
| title=Modern human origins
| last=Wolpoff
| first=MH
|author2=JN Spuhler |author3=FH Smith |author4=J Radovcic |author5=G Pope |author6=DW Frayer |author7=R Eckhardt |author8=G Clark
| date=1988
| journal=Science
| volume=241
| issue=4867
| pages=772–4
| url=http://science.sciencemag.org/content/241/4867/772
| pmid=3136545
| bibcode=1988Sci...241..772W
}}</ref> provides another explanation for the pattern of human evolution.
Multiregional origin holds that the [[Human evolution|evolution of humanity]] 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.


==Recent evolution==
==Recent evolution==

Revision as of 09:34, 21 April 2018

This article is about Homo sapiens as a taxonomic classification. For a more general perspective on the extant human species, see Human. For other uses, see Homo sapiens (disambiguation).

Main articles: Human taxonomy and Anatomically modern human

Early modern human
Temporal range: 0.3–0 Ma
↓
 Middle Pleistocene–Present
Akha man and woman in northern Thailand – husband carries stem of banana-plant, which will be fed to their pigs
Male and female H s. sapiens
(Akha in northern Thailand,
2010 photograph)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Hominidae
Subfamily: Homininae
Tribe: Hominini
Genus: Homo
Species:
H. sapiens
Binomial name
Homo sapiens
Linnaeus, 1758
Subspecies

H. s. sapiens
†H. s. idaltu
†H. s. neanderthalensis(?)
†H. s. rhodesiensis(?)
(others proposed)

Homo sapiens is the systematic name used in taxonomy (also known as binomial nomenclature) for anatomically modern humans, i.e. the only extant human species. The name is Latin for "wise man" and was introduced in 1758 by Carl Linnaeus (who is himself also the type specimen).

Extinct species of the genus Homo are classified as "archaic humans". This includes at least the separate species Homo erectus, and possibly a number of other species (which are variously also considered subspecies of either H. sapiens or H. erectus). H. sapiens idaltu (2003) is a proposed extinct subspecies of H. sapiens.

The age of speciation of H. sapiens out of ancestral H. erectus (or an intermediate species such as Homo heidelbergensis) is estimated to have taken place at roughly 300,000 years ago. Sustained archaic admixture is known to have taken place both in Africa and (following the recent Out-Of-Africa expansion) in Eurasia, between about 100,000 to 30,000 years ago.

Name and taxonomy

Main article: Human taxonomy
Further information: Homo and Names for the human species

The binomial name Homo sapiens was coined by Carl Linnaeus (1758).[2] The Latin noun homō (genitive hominis) means "human being."

Extant human populations have historically been divided into subspecies, but since c. the 1980s all extant groups tend to be subsumed into a single species, H. sapiens, avoiding division into subspecies altogether.[3]

Some sources show Neanderthals (Homo neanderthalensis) as a subspecies (Homo sapiens neanderthalensis).[4][5] Similarly, the discovered specimens of the Homo rhodesiensis species have been classified by some as a subspecies (Homo sapiens rhodesiensis), although it remains more common to treat these last two as separate species within the genus Homo rather than as subspecies within H. sapiens.[6]

Age and speciation process

Further information: Anatomically modern humans
Further information: Human evolution, Homo, Timeline of human evolution, and Early human migrations
Schematic representation of the emergence of H. sapiens from earlier species of Homo. The horizontal axis represents geographic location; the vertical axis represents time in millions of years ago (blue areas denote the presence of a certain species of Homo at a given time and place; late survival of robust australopithecines alongside Homo is indicated in purple). Based on Springer (2012), Homo heidelbergensis[7] is shown as diverging into Neanderthals, Denisovans and H. sapiens. With the rapid expansion of H. sapiens after 60 kya, Neanderthals, Denisovans and unspecified archaic African hominins are shown as again subsumed into the H. sapiens lineage.

The speciation of H. sapiens out of varieties of H. erectus is estimated as having taken place between 300,000 and 200,000 years ago.

Since the 1970s, the Omo remains, dated to some 195,000 years ago, have often been taken as the conventional cut-off point for the emergence of "anatomically modern humans". Since the 2000s, the discovery of older remains with comparable characteristics, and the discovery of ongoing hybridization between "modern" and "archaic" populations after the time of the Omo remains, have opened up a renewed debate on the "age of Homo sapiens", in journalistic publications cast into terms of "Homo sapiens may be older than previously thought".[8]

Homo sapiens idaltu, dated to 160,000 years ago, has been postulated as an extinct subspecies of Homo sapiens in 2003.[9] Homo neanderthalensis, which became extinct 30,000 years ago, has also been classified as a subspecies, Homo sapiens neanderthalensis; genetic studies now suggest that the functional DNA of modern humans and Neanderthals diverged 500,000 years ago.[10]

Dispersal and archaic admixture

Dispersal of early H. sapiens begins soon after its emergence.

The Khoi-San of Southern Africa may be the human population with the deepest temporal division from all other contemporary populations, estimated at close to 130,000 years ago. A 2011 study has classified them as an "ancestral population cluster". The same study also located the origin of the first wave of expansion of H. sapiens, beginning roughly 130,000 years ago, in southwestern Africa, near the coastal border of Namibia and Angola.[11] A 2017 analysis suggested that the Khoi-San diverged from West African populations even earlier, between 260,000 and 350,000 years ago, compatible with (an upper limit of) the age of H. sapiens.[12] Homo sapiens idaltu, found at site Middle Awash in Ethiopia, lived about 160,000 years ago.[13] The discovery of fossils attributed to H. sapiens, along with stone tools, dated to approximately 300,000 years ago, found at Jebel Irhoud, Morocco was announced in 2017.[14]

Early H. sapiens may have reached Asia in a first wave as early as 120,000 years ago.[15][16][17] Evidence presented in 2017 raises the possibility that a yet earlier migration, dated to around 270,000 years ago, may have left traces of admixture in Neanderthal genome.[18]

The Recent "Out of Africa" migration of Homo sapiens took place in at least two waves, the first around 130,000 to 100,000 years ago, the second (Southern Dispersal) around 70,000 to 60,000 years ago. Evidence for the overwhelming contribution of the "recent African origin" of modern populations outside of Africa was established based on mitochondrial DNA, combined with evidence based on physical anthropology of archaic specimens, during the 1990s and 2000s.</ref>Liu, Hua; et al. (2006). "A Geographically Explicit Genetic Model of Worldwide Human-Settlement History". The American Journal of Human Genetics. 79 (2): 230–237. doi:10.1086/505436. PMC 1559480. PMID 16826514. Currently available genetic and archaeological evidence is generally interpreted as supportive of a recent single origin of modern humans in East Africa. "Out of Africa Revisited". Science. 308 (5724): 921g. 2005-05-13. doi:10.1126/science.308.5724.921g. Retrieved 2009-11-23.</ref> The assumption of complete replacement has been revised in the 2010s with the discovery admixture events (introgression) of populations of H. sapiens with populations of archaic humans have been discovered as having taken place between roughly 100,000 and 30,000 years ago, both in Eurasia and in Sub-Saharan Africa. The extent of Neanderthal admixture (and introgression of genes acquired by admixture) varies significantly between contemporary racial groups, being absent in Africans, intermediate in Europeans and highest in East Asians. Certain genes related to UV-light adaptation introgressed from Neanderthals have been found to have been selected for in East Asians specifically from 45,000 years ago until around 5,000 years ago.[19] Cumulatively, about 20% of the Neanderthal genome is estimated to remain present in contemporary populations.[20] The extent of archaic admixture is of the order of about 1% to 4% in Europeans and East Asians, and highest among Melanesians (Denisova hominin admixture), at 4% to 6%.[21]

Recent evolution

Further information: Recent human evolution, Human genetic variability, and Race and genetics

Following the second Out-of-Africa expansion, some 70,000 to 50,000 years ago, some subpopulations of H. sapiens have been essentially isolated for tens of thousands of years prior to the early modern Age of Discovery.

Combined with archaic admixture this has resulted in significant genetic variation, which in some instances has been shown to be the result of directional selection taking place over the past 15,000 years, i.e. significantly later than possible archaic admixture events.[22]

Some climatic adaptations, such as high-altitude adaptation in humans, are thought to have been acquired by archaic admixture. Inuit adaptation to high-fat diet and cold climate has been traced to a mutation dated the Last Glacial Maximum (20,000 years ago).[23] Adaptations related to agriculture and animal domestication, such as the East Asian types of ADH1B associated with rice domestication,[24] or lactase persistence,[25] are due to recent selection pressures. Similarly, adaptations in spleen size and pupil-controlling muscles which enhance underwater sight in the Austronesian Sama-Bajau have developed under selection pressures associated with subsisting on freediving over the past thousand years or so.[26]

Physiological or phenotypical changes have also been traced to recent (Upper Paleolithic) mutations, such as the East Asian variant of the EDAR gene, dated to c. 35,000 years ago.[27] Alleles predictive of light skin have been found in Neanderthals, [28] but the alleles for light skin in Europeans and East Asians, associated with, KITLG and ASIP, are (as of 2012) thought to have not been acquired by archaic admixture but recent mutations (later than 30,000 years ago).[29]

References

  1. ^ Global Mammal Assessment Team (2008). "Homo sapiens". The IUCN Red List of Threatened Species. 2008. IUCN: e.T136584A4313662. doi:10.2305/IUCN.UK.2008.RLTS.T136584A4313662.en. Retrieved 12 January 2018.
  2. ^ Linné, Carl von (1758). Systema naturæ. Regnum animale (10th ed.). pp. 18, 20. Retrieved 19 November 2012..
  3. ^ The history of claimed or proposed subspecies of H. sapiens is complicated and fraught with controversy. The only widely recognized archaic subspecies is H. sapiens idaltu (2003). The name H. s. sapiens is due to Linnaeus (1758), and refers by definition the subspecies of which Linnaeus himself is the type specimen. However, Linnaeus postulated four other extant subspecies, viz. H. s. afer, H. s. americanus, H. s. asiaticus and H. s. ferus for Africans, Americans, Asians and Malay. This classification remained in common usage until the mid 20th century, sometimes alongide H. s. tasmanianus for Australians. See e.g. John Wendell Bailey, The Mammals of Virginia (1946), p. 356.; Journal of Mammalogy 26-27 (1945), p. 359.; The Mankind Quarterly 1-2 (1960), 113ff ("Zoological Subspecies of Man"). The division of extant human populations into taxonomic subspecies was gradually given up in the 1970s (e.g. Grzimek's Animal Life Encyclopedia, Volume 11, p. 55).
  4. ^ Hublin, J. J. (2009). "The origin of Neandertals". Proceedings of the National Academy of Sciences. 106 (38): 16022–7. Bibcode:2009PNAS..10616022H. doi:10.1073/pnas.0904119106. JSTOR 40485013. PMC 2752594. PMID 19805257.
  5. ^ Harvati, K.; Frost, S.R.; McNulty, K.P. (2004). "Neanderthal taxonomy reconsidered: implications of 3D primate models of intra- and interspecific differences". Proc. Natl. Acad. Sci. U.S.A. 101 (5): 1147–52. Bibcode:2004PNAS..101.1147H. doi:10.1073/pnas.0308085100. PMC 337021. PMID 14745010.
  6. ^ "Homo neanderthalensis King, 1864". Wiley-Blackwell Encyclopedia of Human Evolution. Chichester, West Sussex: Wiley-Blackwell. 2013. pp. 328–331.
  7. ^ Stringer, C. (2012). "What makes a modern human". Nature. 485 (7396): 33–35. doi:10.1038/485033a. PMID 22552077.
  8. ^ "New Clues Add 40,000 Years to Age of Human Species – NSF – National Science Foundation". www.nsf.gov. "Age of ancient humans reassessed". BBC News. February 16, 2005. Retrieved April 10, 2010. The Oldest Homo Sapiens: – URL retrieved May 15, 2009 Alemseged, Z.; Coppens, Y.; Geraads, D. (2002). "Hominid cranium from Homo: Description and taxonomy of Homo-323-1976-896". Am J Phys Anthropol. 117 (2): 103–12. doi:10.1002/ajpa.10032. PMID 11815945. Stoneking, Mark; Soodyall, Himla (1996). "Human evolution and the mitochondrial genome". Current Opinion in Genetics & Development. 6 (6): 731–6. doi:10.1016/S0959-437X(96)80028-1.
  9. ^ 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.
  10. ^ Green, R. E.; Krause, J; Ptak, S. E.; Briggs, A. W.; Ronan, M. T.; Simons, J. F.; et al. (2006). Analysis of one million base pairs of Neanderthal DNA. Nature. pp. 16, 330–336.
  11. ^ Henn, Brenna; Gignoux, Christopher R.; Jobin, Matthew (2011). "Hunter-gatherer genomic diversity suggests a southern African origin for modern humans". Proceedings of the National Academy of Sciences of the United States of America. 108 (13). National Academy of Sciences: 5154–62. Bibcode:2011PNAS..108.5154H. doi:10.1073/pnas.1017511108. PMC 3069156. PMID 21383195.
  12. ^ Schlebusch; et al. (3 November 2017). "Southern African ancient genomes estimate modern human divergence to 350,000 to 260,000 years ago". Science. 358 (6363): 652–655. doi:10.1126/science.aao6266.
  13. ^ White, Tim D.; Asfaw, Berhane; Degusta, David; Gilbert, Henry; Richards, Gary D.; Suwa, Gen; Howell, Clark F. (June 2003). "Pleistocene Homo sapiens from Middle Awash, Ethiopia". Nature. 423 (6941): 742–7. Bibcode:2003Natur.423..742W. doi:10.1038/nature01669. PMID 12802332.
  14. ^ Callaway, Ewan (7 June 2017). "Oldest Homo sapiens fossil claim rewrites our species' history". Nature. doi:10.1038/nature.2017.22114. Retrieved 11 June 2017.
  15. ^ Bae, Christopher J.; Douka, Katerina; Petraglia, Michael D. (8 December 2017). "On the origin of modern humans: Asian perspectives". Science. 358 (6368): eaai9067. doi:10.1126/science.aai9067. Retrieved 10 December 2017.
  16. ^ Kuo, Lily (10 December 2017). "Early humans migrated out of Africa much earlier than we thought". Quartz. Retrieved 10 December 2017.
  17. ^ Ankita Mehta (26 January 2018). "A 177,000-year-old jawbone fossil discovered in Israel is oldest human remains found outside Africa". International Business Times.
  18. ^ Posth, Cosimo; et al. (4 July 2017). "Deeply divergent archaic mitochondrial genome provides lower time boundary for African gene flow into Neanderthals". Nature Communications. doi:10.1038/ncomms16046. Retrieved 4 July 2017.
  19. ^ Ding, Q.; Hu, Y.; Xu, S.; Wang, J.; Jin, L. (2014) [Online 2013]. "Neanderthal Introgression at Chromosome 3p21.31 was Under Positive Natural Selection in East Asians". Molecular Biology and Evolution. 31 (3): 683–695. doi:10.1093/molbev/mst260. PMID 24336922.
  20. ^ Vernot, B.; Akey, J. M. (2014). "Resurrecting Surviving Neandertal Lineages from Modern Human Genomes". Science. 343 (6174): 1017–1021. Bibcode:2014Sci...343.1017V. doi:10.1126/science.1245938. PMID 24476670.
  21. ^ Green, RE; Krause, J; Briggs, AW; Maricic, T; Stenzel, U; Kircher, M; Patterson, N; Li, H; Zhai, W; Fritz, M. H. Y.; Hansen, N. F.; Durand, E. Y.; Malaspinas, A. S.; Jensen, J. D.; Marques-Bonet, T.; Alkan, C.; Prufer, K.; Meyer, M.; Burbano, H. A.; Good, J. M.; Schultz, R.; Aximu-Petri, A.; Butthof, A.; Hober, B.; Hoffner, B.; Siegemund, M.; Weihmann, A.; Nusbaum, C.; Lander, E. S.; Russ, C.; et al. (2010). "A Draft Sequence of the Neandertal Genome". Science. 328 (5979): 710–22. Bibcode:2010Sci...328..710G. doi:10.1126/science.1188021. PMC 5100745. PMID 20448178. {{cite journal}}: Invalid |ref=harv (help). Reich, D.; Green, R.E.; Kircher, M.; Krause, J.; Patterson, N.; Durand, E.Y.; et al. (2010). "Genetic history of an archaic hominin group from Denisova Cave in Siberia". Nature. 468 (7327): 1053–1060. Bibcode:2010Natur.468.1053R. doi:10.1038/nature09710. PMC 4306417. PMID 21179161..
  22. ^ Wade, N (2006-03-07). "Still Evolving, Human Genes Tell New Story". The New York Times. Retrieved 2008-07-10.
  23. ^ Matteo Fumagalli et al., "Greenlandic Inuit show genetic signatures of diet and climate adaptation", Science Vol. 349, Issue 6254, 18 Sep 2015, pp. 1343-1347, DOI: 10.1126/science.aab2319
  24. ^ Peng, Y. et al. The ADH1B Arg47His polymorphism in East Asian populations and expansion of rice domestication in history. BMC Evolutionary Biology 10, 15 (2010).
  25. ^ Ségurel, Laure; Bon, Céline (2017). "On the Evolution of Lactase Persistence in Humans". Annual Review of Genomics and Human Genetics. 18 (1): 297–319. doi:10.1146/annurev-genom-091416-035340. PMID 28426286. Ingram, Catherine J. E.; Mulcare, Charlotte A.; Itan, Yuval; Thomas, Mark G.; Swallow, Dallas M. (2008-11-26). "Lactose digestion and the evolutionary genetics of lactase persistence". Human Genetics. 124 (6): 579–591. doi:10.1007/s00439-008-0593-6. ISSN 0340-6717.
  26. ^ Ilardo, M. A.; Moltke, I.; Korneliussen, T. S.; Cheng, J.; Stern, A. J.; Racimo, F.; de Barros Damgaard, P.; Sikora, M.; Seguin-Orlando, A.; Rasmussen, S.; van den Munckhof, I. C. L.; ter Horst, R.; Joosten, L. A. B.; Netea, M. G.; Salingkat, S.; Nielsen, R.; Willerslev, E. (2018-04-18). "Physiological and Genetic Adaptations to Diving in Sea Nomads". Cell. 173 (3): 569–580.e15. doi:10.1016/j.cell.2018.03.054. Gislén, A., Dacke, M., Kröger, R.H., Abrahamsson, M., Nilsson, D.-E., and Warrant, E.J., "Superior underwater vision in a human population of sea gypsies." Curr. Biol. 2003; 13: 833–836.
  27. ^ Traits affected by the mutation are sweat glands, teeth, hair thickness and breast tissue. Kamberov et al., "Modeling Recent Human Evolution in Mice by Expression of a Selected EDAR Variant", Cell Volume 152, Issue 4, p691–702, 14 February 2013, DOI: https://dx.doi.org/10.1016/j.cell.2013.01.016. Journalistic report: East Asian Physical Traits Linked to 35,000-Year-Old Mutation, NYT, 14 February 2013.
  28. ^ Lalueza-Fox; Römpler, H; Caramelli, D; Stäubert, C; Catalano, G; Hughes, D; Rohland, N; Pilli, E; Longo, L; Condemi, S; de la Rasilla, M; Fortea, J; Rosas, A; Stoneking, M; Schöneberg, T; Bertranpetit, J; Hofreiter, M; et al. (2007). "A melanocortin-1 receptor allele suggests varying pigmentation among Neanderthals". Science. 318 (5855): 1453–1455. doi:10.1126/science.1147417. PMID 17962522.
  29. ^ Belezal, Sandra; Santos, A. M.; McEvoy, B.; Alves, I.; Martinho, C.; Cameron, E.; Shriver, M. D.; Parra, E. J.; Rocha, J. (2012). "The timing of pigmentation lightening in Europeans". Molecular Biology and Evolution. 30 (1): 24–35. doi:10.1093/molbev/mss207. PMC 3525146. PMID 22923467.

External links

Wikimedia Commons has media related to Homo sapiens.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Early_modern_human&oldid=837515557"