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=Multiregional Evolution=

draft { {Expert-subject-multiple|Evolutionary biology|Anthropology|Human Genetic History|date=June 2009}} (where are experts?)

The multiregional hypothesis or orginally multiregional evolution is a model to account for the pattern of human evolution, proposed by Milford H. Wolpoff in 1988. The multiregional evolution holds that the evolution of humanity from the beginning of the Pleistocene 2.5 million years BP to the present day has been within a single, continuous human species, evolving worldwide to modern Homo sapiens.

fossil and genomic data do not contradict multiregional evolution thesis. The gene flow and sexual reproduction between modern and ancestral human population has not been ruled out,  and what is more important multiregional evolution has not been statistically rejected. The other competing theory: Recent African replacement postulate (akaRAO/OOA/noah ark theory/Adam gardener/Eden/mito-Eve..e.t.c (why so many catchy names?)) has been statistically rejected by 'nested clade analysis NCPA'

2009 statistical analysis over available NIH data find evidence for ancient admixture, suggesting this may be a general feature of recent human evolution.

The other popular theory on human evolution is recent African origin of modern humans (RAO) - also known as "Out of Africa".

Regional continuity
The term "multiregional hypothesis" was first coined in the early 1980s by Milford H. Wolpoff and colleagues as an explanation for the apparent similarities seen in Homo erectus and Homo sapiens fossils from the same region, what they called regional continuity.

Wolpoff rejected the earlier proposal by Coon of parallel evolution, and proposed a theory based on clinal variation that would allow for the necessary balance between local selection and a global species. He proposed that Homo erectus, Neanderthals, Homo sapiens and other humans were a single species. This species arose in Africa two million years ago as H. erectus and then spread out over the world, developing adaptations to regional conditions. It was proposed that for periods of time some populations became isolated, developing in a different direction, but through continuous interbreeding, replacement, genetic drift and selection, adaptations that were an advantage anywhere on earth would spread, keeping the development of the species in the same overall direction, while maintaining adaptations to regional factors. Eventually, the more unusual local varieties of the species would have disappeared in favor of modern humans, retaining some regional adaptations, but with many common features.

Fossil evidence
Some proponents of the multiregional hypothesis, including Wolpoff, argue that fossil evidence is more reliable than estimates based on genetic evidence and molecular clocks, which they contend are subject to genetic drift, bottlenecks and other complicating factors.

Neanderthals
Com.:Abrigo do Lagar Velho is clasified as EEMH with nenderthal traits perhaps title Nendrthals is not sholuld reflect this niuans

Multiregionalists claimed that the discovery of a possible hybrid Homo sapiens X neanderthalensis fossil child at the Abrigo do Lagar Velho rock-shelter site in Portugal in 1999 further supports the multiregional hypothesis, by reflecting the admixture of diverse human populations. Two other archaeologists dispute this: "the analysis by Duarte et al. of the Lagar Velho child's skeleton is a brave and imaginative interpretation, of which it is unlikely that a majority of paleoanthropologists will consider proven."

In an article appearing in the Proceedings of the National Academy of Sciences in 2007, Erik Trinkaus has brought together the available data, which shows that early modern humans did exhibit evidence of Neanderthal traits, saying, "When you look at all of the well dated and diagnostic early modern European fossils, there is a persistent presence of anatomical features that were present among the Neandertals but absent from the earlier African modern humans...Early modern Europeans reflect both their predominant African early modern human ancestry and a substantial degree of admixture between those early modern humans and the indigenous Neandertals."

Peking man
Shang et al see continuity in skeletal remains of archaic people from east Asia.

Early modern humans
Wolpoff and colleagues published an analysis in 2001 of character traits of the skulls of early modern human fossils, which failed to reject a theory of dual ancestry from Javan Homo erectus for Australian early modern humans and Neanderthals for Central European modern humans, and which they said ruled out a replacement model. A subsequent analysis comparing differences of Neanderthal skulls to those of modern humans using 3D morphometric techniques showed a large difference between the two populations, such that Harvatti & al concluded that "we interpret the evidence presented here as supporting the view that Neanderthals represent an extinct human species and therefore refute the regional continuity model for Europe." It has been argued that these differences are consistent with an evolving lineage, as ancestors are never identical to their descendants.

New early modern human remains were unearthed in 2003 in Tianyuan Cave, Zhoukoudian. 14C dated 42-39 ky Tianyuan 1 holotype is the oldest, directly dated EMH in eastern Eurasia. Tianyuan 1 exhibits a series of typical modern, derived modern human features and few archaic traits. Some late archaic human traits include a large hamulus length, anterior to posterior dental proportions and a broad and rounded distal phalangeal tuberosityhis.

The oldest European EMH remains were discovered in 2002 in cave named Peştera cu Oase near the Iron Gates in the Danubian corridor. Oase 1 holotype revealed specific traits combining a variety of archaic Homo traits, derived early modern humans, and possibly Neanderthal features. Modern human attributes place it close to European early modern humans among Late Pleistocene samples. The fossil belongs to the few findings in Europe which could be directly dated and is considered the oldest known early modern human fossil from Europe. Two laboratories independently yielded microfiltrated collagen with 14C averaging to 34,950 B.P. In Europe around 40-30 ka evolved latitudinal cline between intermixed Neanderthal traits on west and EEMH on east. The human population phenotypic continuity exist in subsequent generations.

Genetic evidence
By analysing haplotype data, Alan Templeton found support for three waves of human migration out of Africa, the first being 1.9 million years ago, and concluded that it was impossible that existing Eurasian populations had not interbred with African migrants.

Studies on past population bottlenecks that can be inferred from molecular data have led multiregionalists to conclude that the recent single-origin hypothesis is untenable because there are no population size bottlenecks affecting all genes that are more recent than 2 million years ago.


 * Microcephalin D allele introgressed into the modern human gene pool points to the Neanderthal lineage as possible source and compelling evidence of admixture among the human loci.
 * RRM2P4 (ribonucleotide reductase M2 subunit pseudogene 4) . Present day human population clades A and B have 2.3 Ma time to most recent common ancestor (TMRCA). The gene tree branches of RRM2P4 point to eastern Asian ancestry.
 * PDHA1 (pyruvate dehydrogenase) locus on X chromosome has estimated coalescent-time depth of 1.86 Ma.
 * MAPT locus 17q21.3 split into deep genetic lineages H1 and H2 . H2 lineage in European population suggest inheritance from Neanderthals.
 * ASAH1. Related to mental activity N-Acylsphingosine Amidohydrolase gene two V and M deep genetic lineages have TMRCA 2.4±.4 Ma. Linkage disequilibrium 62% and small nucleotide diversity 0.05% indicate a signature of positive Darwinian selection for the V lineage. The M lineage is attributed to ancient population structure of humans in Africa.
 * X-chromosome genes DMD44, APXL, AMELX, TNFSF5 show S-N heterogeneous patterns of variation and may play role in diversity-reducing selection in non-africans.
 * CMAH CMP-N-acetylneuraminic acid hydroxylase pseudogene show 2.9 Ma genetic history.
 * NAT2 SNPs cluster predictably with linages originating in sub-Saharan Africa, Europe, and East Asia. NAT1*11A 0.29 Ma suggest ancient structured population with gene tree rooted in Eurasia..
 * ALMS1 suggest ancient and complex evolutionary history.
 * Genome polymorphism: Inversion polymorphism: known 5-million-base pair (Mbp) 8p23.1, 1-Mbp on 17q21.3 and novel 1.2-Mbp on 15q24, 2.1-Mbp 15q13, 1.7-Mbp 17q12 . In the sample of 8 gnomes from worldwide sample including Yuruba Kidd&al group found 4 million SNPs and 796,273 small indels (1−100 bp in size); 15 large regions of excess nucleotide variation 500 kbp to 3 Mbp. Two of variable sites are described detailed above.

Proponents of the multiregional hypothesis show genetic sequences of several loci in the human genome with million year old genealogy. Those data of deep genetic lineages are explained in the multiregional theory framework as a result of heredity from structured ancestral population. The data are not interpreted in light of the RAO hypothesis postulating recent replacement where separated million years ago genetic lineages are at best unpredicted.

recent African replacement versus multiregional hypothesis, discussion
Despite being "shaken" early
 * 19 March 1999 *Genetic Study Shakes Up Out of Africa Theory

RAR gained popularity to the level cited as mainsream in media (in mainstreammedia:) and near consesnus ...(below)

A competing theory, the recent African origin of modern humans (also known under multitude of catchy names, e.g. as "Out of Africa"), has emerged as the near consensus view since the 1990s, proposing that modern humans arose in Africa around 100-200,000 years ago, moving out of Africa around 50-60,000 years ago to replace existing human species such as Homo erectus and the Neanderthals.

Genetic data from Monophyletic hapologrups gave strong support to the recent African replacement scenario. However, this is where the near consensus on human settlement history ended, and considerable uncertainty clouded any more detailed aspects. Progres in genomics refutes an exclusively African origin of humans, when genetic data are used in a hypothesis-testing framework, the out-of-Africa replacement hypothesis is strongly rejected. Nested clade analysis

Recent work in this area supports a view of several dispersions out of Africa, with the later two corresponding roughly to the appearance of the morphospecies Homo heidelbergensis and modern H. sapiens, but in both cases showing evidence of dispersions with admixture, rather than dispersions with replacement

Ancient mitochondrial DNA sequence, extracted from 37,000 years old Neanderthal specimen, and mitochondrial DNA from present day humans have different sequence. However, the largest example of sequenced Neanderthal nuclear DNA comprised 1 million base pairs compared to a human nuclear genome size of roughly 3 billion base pairs. This amounts to a comparison of only 0.033% of the genomes.

although there is not yet evidence for any extant 37,000 year or older mitohondrial aDNA still surviving up until today.

''Essentially, there are two schools of thought, described as the short-range and long-range theories, sometimes called the “discontinuist” and the “gradualist” models (d’Errico and Nowell 2000). These two diametrically opposed conceptions perceive two entirely different paths of non-physical human evolution. The short-range model rejects all evidence of symbol use prior to about 40,000 years BP, insisting that it commenced as part of the claimed cognitive revolution at the beginning of the Upper Palaeolithic. In the last few years the resolve of its protagonists has begun to wane somewhat as they have made first concessions and are tinkering with some aspects of their theory, but it still remains the dominant model in archaeology. ''L2

recent timeline ME-RAR debae

 * placeholder for futher section/article (now 'random')


 * 8 March 1996:{10.1126/science.271.5254.1364} "Two camps have been arguing--using both genes and fossils" for 10a. Now.. in one of the largest studies to date of nuclear DNA, .. the data hold new and informative patterns .. all human travels back to Africa, 100,000 years ago.

October 2009
Please do not add defamatory content to Wikipedia. If you would like to experiment please use the sandbox. ''You are apparently also editing as user:76.16.183.158 and your message is an unacceptable anti-Semitic remark. Please note that any edits by your IP address are counted as part of your edits. '' Dougweller (talk) 10:51, 5 October 2009 (UTC)

Multiregional evolution article
Just wanted to thank you for adding a lot of peer reviewed sources to the Multiregional origin of modern humans article a couple years ago. I've rewritten the article, but retained almost all the sources; the rewrite was mostly to make the article more attractive and understandable for a lay audience. If you have any comments, please let me know. — Preceding unsigned comment added by Warren Dew (talk • contribs) 04:58, 9 January 2011 (UTC)

ArbCom elections are now open!
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