The greatest migration of humanity

where do humans come from? How can we be present where we live? Starting from a group of hunters gathering all over Africa, until 200,000 years later, more than 6.5 million of their descendants spread all over the world.

History of a chromosome

Genetic mutations persist for a long time. The earliest known mutant outside the black continent is M168 that dates back 50,000 years. The diagram above describes the Y chromosome of some Native Americans with different mutations.

Cell: cell

Nucleus with chromosomes: Human chromatin

Y chromosome: Y chromosome

DNA patterns: DNA patterns

Hereditary DNA mutationa: Genetic DNA mutations

Ancestral ( Ancestral ): All men carry the same basic configuration originating from Africa.

Out of Africa : Outside of Africa: Migrants from Africa brought along a new M168 model discovered in all non-Africans.

Eurasian (Asian - European): M9 is popular among Eurasian people, appearing in the Middle East or Central Asia.

Amerindian (Indian): M3 is present in Asian residents and from here they moved to the Americas. Scientists have long believed that modern humans are of continental origin because they discovered the oldest bone samples here. Geneticists have similar conclusions after extensive studies of African genes' traits.

However, many people are still apprehensive about the path our ancestors migrated out of Africa and dispersed throughout the planet once upon a time. A human skull dating to about 92,000 years found in the archaeological site of Qafzah, Israel has shown that humans have made their first migrations and these ancient people may have moved north. across the Nile Valley to the Middle East.

In addition, other immigrants out of Africa tens of thousands of years later may have followed a different path: crossing the northern Red Sea region. Many scientists say these same "wandering people" have created an estimated 5.5 million people currently living outside the black continent.

Genes are the key to every secret

To this day, many scientists still have no answer to the question of who is the first modern human in Africa and what motivates their descendants to leave the homeland of about 50,000. last year to expand Asia - Europe. What time and how can the first person set foot on America?

Others living in the Andaman Islands off Myanmar carry in themselves the oldest homologous genetic markers discovered outside Africa - evidence that modern humans (Homo sapiens) have come to the east. from Africa about 70,000 years ago.Throughout the migration process, they have increased the number of descendants and created new ethnic groups.

Over the decades, the only evidence to answer these questions is based on the bones and artifacts that our ancestors left in their journey. However, over the past 20 years, scientists have relied on DNA samples of today's humans to redefine human migration. "Every single drop of our blood contains a long history written in the language of the evolutionary gene," said Spencer Wells, an ethnographer of the National Geographic magazine.

The human genome, or genome, accounts for 99.9% of human origin in the world, the rest is only a DNA task of individual differences such as eye color or origin. sick people . as well as some do not clearly show its function. By comparing the signs in many different peoples, scientists can learn about the relationship with their ancestors. In most genomes, these rapid changes are covered by genetic changes that occur every time in the DNA of the mother and father during the formation of the next generation. One so-called DNA mitochondria (mtDNA) is transferred intact from mother to child, most Y chromosomes, male chromosomes, are passed from father to child.

Long-term mutations in your mtDNA and (male) Y chromosomes are just two threads linked in a giant carpet of people contributing to our genetics. However, when comparing mtDNA and Y chromosomes of people from different ethnic groups, geneticists can know for sure when and where these groups of people turn in different directions. Their big migration across the planet.

Discover the chromosomes of Adam and Eva

Klaas Kruiper, a hunter of the San tribe, is waiting for family members in the Kalahari desert of South Africa.Genetic common points in the San ethnic group may show a connection to modern people.They communicate with each other - a factor found in the language spoken by other African groups who carry the DNA of an ancient ancestor.

In the mid-80s, the late Professor Allan Wilson and colleagues at the University of California (USA) used mtDNA to determine the origin of human ancestors. They compared mtDNA from many women around the world and found that women of African descent have twice the diversity of their previous generations. From here, these distinct mutations seem to occur at a stable level and modern humans may have lived in Africa twice as long as those in many other places. Scientists now calculate that the existing human being is related to an independent woman who lived nearly 150,000 years ago in Africa, which is considered a "mitochondrial Eva". This woman was not the only one at the time, but if geneticists correctly calculated, all of us humans today are related to Eva through a chain of mothers!

Eva's body quickly gained the "Y chromosome of Adam", the common father of all of us, also from Africa. Further DNA research has also confirmed one thing for sure: the origin of humanity on earth today has ancestors from the hunter-gatherers in Africa.

The greatest migration of human history

The diversity of different genetic groups (colorful dots) shows that Africa is the earliest homeland of modern humans.Groups of people with genetic patterns left Africa (in the middle) and for more than tens of thousands of years, they have settled in different regions (right).

Between 50,000 and 70,000 years ago, a small "wave" of immigrants from Africa reached the shores of western Asia. Archaeologists think that the exodus from the black continent has opened a revolution in behavior, including many complex instruments, extensive social networks and the first types of jewelry and fine arts. of humanity. Maybe some neurological mutations have created spoken language and brought our ancestors more civilized, a small group of them began to find their settlements around the world.

In Asia, scientists have discovered evidence that the first migrants have appeared here. In the Nile Valley, along the Sinai Peninsula and north of the Levant, they used primitive underwater fishing gear. Genetic evidence in Asia shows that migrants have a different separation. A group settled for a short time in the Middle East, while another group traveled along the coast across the Arabian Peninsula, India and beyond. Each subsequent generation moved to some place farther away than the generation of fathers who had settled.

Over thousands of years, the slow movements of people have brought them to southern Australia. Here archaeologists found a corpse of a man buried in a place called Lake Mungo, dating back about 45,000 years ago. Fossilized artifacts underneath the grave can date up to 50,000 years - the earliest evidence of modern human migration from Africa. A number of indigenous groups on the Andaman Islands near Myanmar, in Malaysia and Papua New Guinea as well as in most of the Aborigines of Australia all have mitochondrial genetic markers from the first migrants.

People today in Asia and Europe have a lot of differences but have the same mtDNA and Y chromosome genetics, showing that they have the same origin as some people.

First foot in the Americas

The man of the Onge tribe

Most scientists today agree that Native Americans (Indians) originate from ancient Asians, who have crossed from Siberia to Alaska at the end of the ice age when the sea level descending and exposing the "land bridge" between two continental regions. For decades, it has been thought that the first Americans came here from about 13,000 years before the end of the ice age, opening a path connecting Canada today. However, some archaeologists claim that they have evidence that these people were there earlier, the Meadowcroft Shelter site in Pennsylvania, which has 16,000 years of age and Monte Verde in the south. Chile, more than 14,000 years old.

DNA samples from living Native Americans may help solve some of these questions. Most of these people carry many DNA markers similar to Asians. Jody Hey, a geneticist at Rutgers University, said: "It is the genes of the Indians today who have spoken of their relationship with their ancestors from ancient times.

Minh Tu

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(1) The cradle of Africa

Most ethnographic and geneticists agree that modern people were present and developed about 200,000 years ago in Africa. Fossils of the first modern humans were found in Omo Kibish, Ethiopia. The relics in Israel also contain evidence of modern people outside Africa, but the group did not move further and died about 90,000 years ago.

(2) Outside the black continent

Genetic data show that a small group of modern people left Africa about 70,000 to 50,000 years ago and replaced other strains like the Neandertals (extinct). All non-Africans are descendants of immigrants who crossed the Red Sea or the south of the region.

(3) The first Australian

Discover at two ancient sites - Malakunanja artifacts and fossils from Lake Mungo - identify modern humans who have traveled along the southern Asian coastal areas and arrived in Australia approximately 50,000 years ago. Their descendants, the Australian Aborigines are still living on the islands of the continent until today.

(4) The first European

Many ethnic ethnographers have long thought that settlers in Europe follow paths from North Africa through the Levant. However, genetic data show that the DNA samples of Western and Western Europeans today belong to Indians. That is likely to show a continental migration from Asia to Europe about 40,000 or 30,000 years ago.

(5) Asian population

About 40,000 years ago, humans crossed Central Asia and reached the northern Himalayas. At the same time, they traveled throughout Southeast Asia and China, setting foot on Japan and Siberia. Genetic evidence confirms that people in North Asia actually migrate to the Americas.

(6) In the New World

The time when the first person was actually present in the Americas is still a problem that has not been solved even though many studies have been published. The genetic evidence showed that this time was about 20,000 - 15,000 years ago, when the sea level was low and the land connected Siberia and Alaska together. The ice sheets probably covered a large area within North America, forcing newcomers to migrate to the west coast.