Early human migrations

Early species of the genus Homo , H.ergaster , H.erectus , and H.heidelbergensis migrated from Africa about 1.9 million years ago. In fact, the dates of the spread of H.ergaster from Africa coincide with the moment of its appearance as a species and the final transition of people to movement on two legs. This happened only 500 thousand years after the emergence of the Homo genus as such, when the monkey people first learned how to make primitive tools of labor of the Olduvai culture . In particular, in Georgia ( Dmanisi ) erectus appeared more than 1.7 million years ago.

The island of Java in Indonesia was inhabited by a local species of erectus about 1.7 million years ago (see Pithecanthropus ), and China by the synanthropes — more than a million years ago ^{[1] [2] [3]} . In Western Europe, erectus appeared about 1.2 million years ago ^[4] . They even suggest that Homo erectus was able to build rafts and cross oceans ^[5] , but this hypothesis is not supported by all scientists. It should be noted that orangutans , who also migrated from Africa, reached Southeast Asia 15 million years earlier than humans.

750 thousand years ago, the ancestors of Neanderthals and Denisovans separated from the line leading to anatomically modern people, left Africa and spread throughout Eurasia at the beginning of the Middle Pleistocene , survived the bottleneck in reducing the population, crossed with Eurasians from the “super-archaic” hominin population (which separated from other Homo about 2 million years ago (confidence interval 1.9-2.5 million years ago) and the first to come out of Africa, 1.7-1.9 million years ago) have largely replaced them and were divided into Eastern e and Western populations - denisovtsev (Denisovans) and Neanderthals (Neanderthals) 731 thousand years ago.. It is possible that Neanderthals and Denisovans received a gene flow from two different “superarchic” populations ^[6] .

Today, the entire serious scientific community adheres to the theory of African descent of man , according to which Homo sapiens appeared in Southeast Africa about 200 thousand years ago and spread from there all over the planet. The concept of African descent is contrasted with the now marginal concept of multi-regional origin , suggesting that Homo erectus has become Homo sapiens independently in different parts of the world.

Since mitochondrial DNA (mtDNA) is inherited only through the maternal line, by comparing its sequence, one can determine the relative relationship of people by their proximity to the hypothetical “ mitochondrial Eve, ” the progenitor of the species Homo sapiens .

Alan Wilson studied mtDNA of people of various origins, and by the number of differences in the nucleotide sequence of mtDNA, he determined the degree of kinship between different groups of people and built a family tree of humanity. The earliest branching point on this tree separates the group of Africans from other people - according to modern data, this happened 137 ± 15 thousand years ago ^[7] .

Thus, according to the estimate of the "molecular biological clock", Eve lived in Africa 120-150 thousand years ago, which approximately corresponds to the age of a person from Idalt from Ethiopia. About 80-100 thousand years ago, the settlement of the ancestral population of Homo sapiens began . The carriers of the mitochondrial haplogroup L1, the ancestors of the Khoisan peoples of Africa , moved to the south, and the carriers of the haplogroup L2, the ancestors of the pygmies , as well as the peoples speaking the Nilo-Saharan and Niger-Congolese languages, moved to the west.

According to estimates, the time of appearance of the Y-chromosomal Adam for 2016 is 275 thousand years ago (95% confidence interval: 245–304 thousand years ago) ^[8] .

There is a widespread theory linking the extinction of the remaining human populations that participated in possible earlier migrations with the catastrophic eruption of the Toba volcano between 77,000 and 69,000 years ago.

Carriers of the mitochondrial haplogroup L3 remained in East Africa and later began to settle in Eurasia. It is assumed that a small group of these people about 70 thousand years ago, when the last ice age began , and the sea ​​level fell, crossed the Red Sea and settled in Arabia . The width of the Bab el-Mandeb Strait today is only 20 km, and in the Ice Age, sea level could be lower by 70 m. Judging by the fossil remains, a significant part of the diet of immigrants were mollusks living in shallow water. Therefore, they had to swim well, possibly had some kind of swimming facilities and were interested in finding new coastal shallows.

According to the theory of coastal migration , a person originally settled from Africa east along the coast ^{[9] [10] [11] [12]} .

Such coastal resettlement later brought people like modern Weddoids or proto- australoids to the Persian Gulf and India , then to the Andaman Islands and Indonesia , and 25 thousand years after the exodus from Africa, the first groups of people reached the coast of Australia ^[13] .

A study of the Neanderthal DNA from the Denisova Cave showed that the eastern (Altai) Neanderthals crossed with anatomically modern people over 100 thousand years ago ^{[14] [15]} .

An analysis of the Australian Aboriginal genome showed that Native Australians, as well as New Guinean highlanders, came from an ancient wave of migrants who entered Southeast Asia 75–62 thousand years ago and crossed with Denisov’s man . Modern Asians come mainly from the second, later wave of immigrants from the West, who separated from the ancestors of modern Europeans and settled Asia about 38-25 thousand years ago, displacing and partially assimilating their predecessors ^{[16] [17]} . Genetic studies of Sahul populations in comparison with studies of other modern human populations showed that Yoruba shared with the Papuans of New Guinea about 90 thousand years ago, and with the rest of the Eurasian populations - 75 thousand years ago, which testifies to the hypothesis that “ the exodus from Africa ”occurred twice - about 120 thousand years ago (xOoA) and about 80 thousand years ago (OoA). The separation of Papuans and Eurasian populations was 40 thousand years ago, a little earlier than the separation of West Eurasian and East Asian populations 30 thousand years ago ^{[18] [19]} . The finding of sapiens aged 194-177 thousand years ago in the Israeli cave of Misliya suggests an earlier exodus from Africa - 220 thousand years ago ^[20] .

The decrease in the level of the world's oceans was the reason for the existence in that era of a large land mass (protruding continental shelf ) that connected the current Great Sunda Islands , which was called Sunda . New Guinea also represented, together with Australia, parts of the single continent of Sahul and separated from Australia by the strait only 8 thousand years ago ^{[21] [22]} .

Another part of the people from Sunda headed north-east to China , where they left a chain of ancient coastal sites. In addition, their descendants, who now inhabit India , China , Indochina , Japan and other regions, received from their ancestors the mitochondrial haplotype M. At the same time, part of the people who lived in the Middle East moved to Central Asia , Siberia and the Far East . Their descendants are characterized by mitochondrial haplogroups A , B and G , isolated about 50 thousand years ago.

The find of the Ust-Ishim man with the Y * chromosome haplogroup K * (xLT) and the mitochondrial haplogroup R , as well as the find of the Sopkargin mammoth, showed that already 45 thousand years ago, a modern-looking man lived in Western Siberia and Taimyr .

It is believed that Homo sapiens came to Europe from Central Asia and the Middle East not earlier than 45 thousand years ago, and its development took at least 15 thousand years ^{[23] [24]} . Neanderthals living here were gradually driven out to the west. In the confrontation with the indigenous inhabitants who lived in Europe for 200 thousand years, on the side of the aliens, known as Cro-Magnons , were more advanced technology and means of communication, that is, a developed language. Neanderthals, although better adapted to the cold climate and physically stronger, were eventually forced to seek the last refuge on the Iberian Peninsula . The last Neanderthal population known to science lived in caves on the northern shore of the Strait of Gibraltar 24-30 thousand years ago.

In addition to the theory of the origin of Homo sapiens sapiens from Africa, there are other hypotheses, in particular, about the origin of modern man from different subspecies of Neanderthals or as a result of crosses between Africans and Neanderthals. It was stated that estimates of differences in the sequence of mitochondrial DNA obtained from fossil remains of Neanderthals with modern humans exclude Homo sapiens neanderthalensis from the ancestors of modern humans ^[25] . It was also pointed out that although Homo neanderthalensis and Homo sapiens coexisted for tens of thousands of years, no remains have been found that would undoubtedly bear traits of both species, and there are doubts that the cross between them could produce prolific offspring ^[26] . However, in 2010, as a result of the decoding of the Neanderthal genome, it was possible to reliably confirm the version of the crossing of Neanderthals with Homo sapiens. In terms of genetic differences, the Neanderthal genome turned out to be more similar to Europeans, Asians and Papuans than to Africans ^[27] .

Luca Cavalli-Sforza compiled frequency distribution maps of several hundred genes in European populations (he called these maps “genetic landscapes”) and calculated the dates of their separation from the genetic distances between the populations.

He managed to reconstruct several waves of human migrations. The first one, which left the most noticeable genetic trace (the frequency of occurrence of a complex of 95 genes gradually decreases from the areas of the Middle East to the Basque habitat), corresponds to the expansion of Neolithic agricultural peoples from the places of origin of agriculture ( Mesopotamia region) to the north and west of Europe. Her dating based on genetic distances coincides with archaeological dating (6-9 thousand years ago).

The frequency of occurrence of another complex of genes is highest in the south of Russia and decreases both towards the north and south of this region. This trail was left by migrations of nomadic herders 4-6 thousand years ago. It is assumed that it was then that Indo-European languages were brought to Europe. The change in the prevalence of the third complex of genes corresponds to the expansion of Greek culture in the 1st millennium BC ^[7] .

America was first populated by the descendants of a small group of people who came from Asia through Alaska . The timing of their penetration remains unclear, but all estimates indicate the last ice age , when sea levels were lower than modern and Siberia was connected to the Alaska land mass, called Beringia . The results of studies conducted by Rutgers University theoretically showed that the entire indigenous population of America came from only 70 individuals who arrived 14–12 thousand years ago along the Bering Isthmus , which existed between Asia and America then ^[28] .

The most ancient archaeological culture of America is the Clovis culture , which arose no later than 11 thousand years ago. At the same time, the age of some Paleolithic sites is estimated at more than 33 thousand years. J. Greenberg and M. Rulen (whose ideas were skeptical by most linguists) divided the languages ​​of the indigenous inhabitants of America into three main macro-families: Amerindian , Naden and Eskimo-Aleutian , which, in their opinion, corresponded to three successive waves of migration to the New World.

In 2004, Stephen Oppenheimer in his book “From Eden” (“Genuine Eve”) wrote that about 50 thousand years ago, carriers of the mitochondrial haplogroup U5 traveled from the Anatolian Peninsula to the northwest to Europe, and carriers of the mitochondrial haplogroup U6 moved along the coast from there the Mediterranean to North Africa ^[29] , the carriers of the mitochondrial haplogroup the M1 , according to a study of the Estonian geneticists Thomas Kivisilda and Richard Willems, crossed the Red sea and passed on the horn of Africa and the Ethiopian highlands about the time of the last ice age ^{[30] [31]} . In 2016, the basal haplogroup U6 * was discovered in the inhabitant of the Romanian , who lived 35 thousand years ago, which indicates the reverse Upper Paleolithic migration from Western Eurasia to North Africa ^{[32] [33]} .

In 2015, it became known about the return migration of representatives of the Y chromosome haplogroup E from Eurasia to Africa after sequencing the genome of the inhabitant of the Ethiopian cave Mota, who lived 4,500 years ago ^[34] . The time of the return to Africa of carriers of the mitochondrial haplogroup L3 is estimated to be 70 thousand years ago, the time of arrival of the carriers of the Y chromosome haplogroup E to Africa is estimated at 65.5 ± 8.5 thousand years ago ^[35] .

About 5700–7300 years ago ( Neolithic subluvial ), carriers of the Y chromosome haplogroup R1b-V88 came from Eurasia to Lake Chad ^[36] .

• Kozintsev A. G. Origin and early history of the species Homo sapiens: new biological data (neopr.) . antropogenez.ru . Date of treatment December 12, 2014.
• In search of a homeland. Excerpt from the book “Genetic Odyssey of Man” by an anthropologist and population geneticist Spencer Wells (neopr.) . postnauka.ru (April 15, 2014).