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The genetic history of North Africa has been heavily influenced by geography. The Sahara desert to the south and the Mediterranean Sea to the North were important barriers to gene flow in prehistoric times. However, Northeast Africa and the Levant form a single land mass at the Suez. At the Straits of Gibraltar, North Africa and Europe are separated by only . At periods of low sea-levels, such as during a glacial maximum, islands that are currently submerged would appear in the Mediterranean and possibly in between the Gibraltar straits. These may have encouraged humans to "island hop" between Africa and Europe. During wetter phases of the Sahara, some Saharan inhabitants would have expanded north into southern parts of North Africa. West Asian populations would have also been attracted to a wet Sahara. West Asian populations could also migrate into Africa via the coastal regions of the Mediterranean. As a result of these geographic influences, the genetic profile of North African populations is a complex mosaic of European, West Asian and Sub-Saharan African influences to variable degrees. Though North Africa has experienced gene-flow from the surrounding regions, it has also experienced long periods of genetic isolation in some parts, allowing a distinctive genetic markers to evolve in some Maghrebi populations, especially in some isolated Berber speaking people. Current scientific debate is concerned with determining the relative contributions of different periods of gene flow to the current gene pool of North Africans. Anatomically modern humans are known to have been present in North Africa during the Upper Paleolithic, 45,000 years ago, as attested by the Aterian culture. With no apparent continuity, 22,000 years ago, the Aterian was succeeded by the Iberomaurusian culture which shared similarities with Iberian cultures. The Iberomaurusian was succeeded by the Capsian, a pre-Neolithic culture. Around 9,000 years ago, the Sahara desert entered a wet phase, the Neolithic Subpluvial, which attracted Neolithic peoples from elsewhere in Africa and the Near East. In historic times, North Africa was occupied by various populations, including the Phoenicians (814–146 BCE), Romans (146 BCE–439 CE), Vandals and Alains (439–534 CE), and Byzantines (534–647 CE). In the 7th century, Islam was diffused in the area. Under the unifying framework of Islam, on the one hand, and the settlement of some Middle Eastern tribes together with the migration of the Moors of Andalusia into the Maghreb (after the Spanish Catholic Reconquista) on the other, a fusion took place that resulted in a new ethnocultural entity all over the Maghreb and Egypt and all contributed to the diffusion of the Arab-Islamic culture among the North African populations. ==Y-chromosome== Haplogroup E is the most prevalent haplogroup amongst the Berbers accounting for up to 87 percent of Y-chromosomes among some Berber populations. Haplogroup E is thought to have emerged in East Africa,〔 and would have later dispersed into North Africa and West Asia. The major subclades of haplogroup E found amongst Berbers belong to E1b1b1, which is believed to have emerged in North Africa. Common subclades include E1b1b1a, E1b1b1b and E1b1b1 *. E1b1b1b is distributed along a west-to-east cline with frequencies that can reach as high as 80 percent in Northwest Africa. E1b1b1a has been observed at low to moderate frequencies among Berber populations with significantly higher frequencies observed in Northeast Africa relative to Northwest Africa.〔 West Eurasian haplogroups, such as Haplogroup J and Haplogroup R1, have also been observed at moderate frequencies. A thorough study by Arredi et al. (2004), which analyzed populations from Algeria, concludes that the North African pattern of Y-chromosomal variation (including both J1 and E3b2 main haplogroups) is largely of Neolithic origin, which suggests that the Neolithic transition in this part of the world was accompanied by demic diffusion of Berber–speaking pastoralists from the Middle East 〔although later papers have suggested that this date could have been as long as ten thousand years ago, with the transition from the Oranian to the Capsian culture in North Africa. (SpringerLink - Journal Article )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Genetic history of North Africa」の詳細全文を読む スポンサード リンク
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