A vast migration of men changed the genetic make-up of men in Spain during the Bronze Age, a study shows.
DNA evidence shows migrants flowing into the Pyrenees, replacing existing male lineage throughout the region within a space of 400 years.
It remains unclear whether there is a violent attack or if a male-centric social structure has an important role.
The result comes from the broadest study of its kind.
The researchers reconstructed the population history of Iberia (modern Spain and Portugal) over 8,000 years ̵
Their study was published in the journal Science.
They took and studied DNA from 403 Iberians who lived between 6,000 BC and AD 1,600.
Bronze Age migrants track some of their ancestors to the Neolithic Peoples (Stone Age) found throughout Europe – including Spain – while others with their genetic make-up are similar to those people living at that time in the plains of Russia.
This settlement of the plains was introduced to Europe by nomadic herders who moved west from Asia and the eastern fringes of Europe.
The early Britons' new converts
Crisis in Age of Age
became a crisis that caused population numbers to plunge into Europe towards the end of the Neolithic period (which first in Bronze Age). Recent studies indicate that the plague may play a role.
As people walk west, they take cultural elements from the people they accompany. In Central Europe, a unique culture known as the Bell Beaker tradition was formed. Beakers and their descendants can promote high-level (uneven) societies in Europe, including Iberia – where they begin to stand from 2,500BC.
Researchers look at the Y chromosome – a DNA pack that is passed down more or less from father to child. It can be used to monitor the heritage of the male line. With nearly 2,000BC, local Y chromosome chromosomes have been removed from the Iberian gene pool, in favor of new arrivals.
When the team reviewed DNA from the entire genome – the entire genetic material found in the nuclei of cells – they found that the Iberian later tracked 40% of their ancestors in the new population.
Newcomers – Bell Beaker origin – brought innovations such as bronze-working (including the manufacture of copper weapons). These may have given them a military advantage over farms during the Age of Age, but perhaps provide higher social status to incoming men.
Patterns of the inheritance
Co-author Iñigo Olalde, from Harvard Medical School, US: It is a mistake to jump to the conclusion that the men of Iberian were killed or forced to lose. "He added:" The archaeological record has no clear evidence of the eruption of violence at this time. "
Rather, the high social status of newcomers may be linked to greater reproductive success. "Their male descendants inherit wealth and social status, and themselves have a higher reproductive success," says Dr. Olalde at BBC News.
A system that emphasizes man's and man's inheritance may be key: "A patrilineal and possibly the patriarchal structure of society further expands the patterns that follow, if only the first son will inherit the property of the tribe, whereas other children move and try to establish their own families, especially the spread of their Y lines in new territories, "he
A substantial replacement of the success occurred at the same time in Britain, where Beakers replaced 90% of ancestors who were there before they arrived.
"At least in the east and in the southeast, we see a change in settlement patterns … which lasts until the coming of the Romans," said co-may Dr. Carles Lalueza-Fox, from the University of Barcelona.
egion, the Iron Age Iberian culture established fortified settlements in high ground.
"The Iberian settled in hill communities and a violent society, outlined in tribal lines. One thing that clearly evolves the social structure that exists in the late Neolithic."
Looking at human remains from an earlier period, the study found that Stone Age hunter-gatherers tracked a significant percentage of their ancestors to some of the earliest settlers in Europe, survived southern Spain until the growth of 6,000 years ago.  The team also studied genome data from Moorish Spain (AD 711-1492), when parts of the peninsula were under the control of the Muslim emir of northern African origin.
North African influences are present in Iberia from at least the Bronze Age. But researchers found a dramatic shift in genetic make-up of people from the Moorish-controlled regions after the medieval "Reconquista", when Christian forces gained control over the peninsula. Conquerors cast out many Muslims, although some were allowed to stay if they converted to Christianity.
While many Moorish people who studied in the study seem to be a 50:50 mix of North African and Iberian ancestors, Modern Iberians have earned almost 50% of their ancestors from Neolithic farmers, 25% from ancient hunters-gatherers, and 20% from steppe people.
Faces from Iberia's past
People from the Iron Age Iberian civilization of the east coast of Spain generally cremated their dead. The process of cremation prevented scientists from getting DNA from these debris. While culture is responsible for good works of art, such as the Dama de Elche sculpture, the Iberians also have a violent side. They led large nails through cut heads of enemies killed in battle and showed them in public spaces as trophies. Some 40 such as heads are found in the Ullastret Iberian settlement, which allows scientists to study DNA from them.
Two study burials have been revealed with a high degree of black African ancestry. Both individuals were from Granada in south-western Spain, where the last Muslim emirate was released until it was conquered by Christians in 1492. One of the people came from a 10th Century cemetery if where the bodies were buried in the Islamic tradition devoted to the direction of Mecca. Other individuals are from the 16th Century, after the Christian conquest of Granada. They are thought to be from the Morisco community – former converts to Christianity (only to be expelled from Spain later).
After the collapse of the Roman Empire, tribes from northern and eastern Europe streamed to Iberia. The Visigoths, who spoke a language related to Swedish, German and English, consume control over the region. They established the Spanish monarch that continues today and introduced the laws that make up the basis of the uses of the Christian kingdoms later. The burials from Pla de l 'Horta in northeastern Spain include a mother and daughter of Visigothic origin. Their genomes suggest that they have recent ancestors from Eastern Europe, whereas DNA from cell batteries, or mitochondria – which goes more or less from mother to child – is a types associated with the East Asian population. It is a sign of the genetic complexity of the Eastern Steppe region where their roots are placed.
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