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Eye of the needle in the history of mankind

Homo sapiens was lucky, it some times was very close. Many of his Relatives have long since disappeared from the face of the Homo erectus or the Neanderthal. But anatomically modern man has survived. And, although since his appearance in front of 300 000 years, only a miniscule few of his kind roamed the earth. A study now shows how close we are to extinction for Homo sapiens: approximately 40 000 years ago lived, therefore, in the whole of Central and Western Europe only accepted about 1,500 people – far less than in the past.

To find out how man spread over the planet, create researchers in the recent time more and more accurate population analyses. Geneticists and archaeologists work together to understand what factors made a way in a certain environment and which led to the Failure. "Many of the population estimates show a repeated regional extinctions and numerous imbalances in the distribution of populations," says Isabell Schmidt from the Institute for prehistoric archaeology, University of Cologne, lead author of the current study in the scientific journal "Plos One". Together with her colleagues Andreas Zimmermann, she creates a detailed picture of the colonization of Europe – with surprising Numbers.

The first modern humans migrated to some 45 000 years ago along the Danube in Central Europe. Shortly thereafter, there was a cultural Explosion, such as the findings of the Swabian Alb show: The people began to paint, carved and fascinating figures of ivory, built flutes and made music. It sounds like an unadulterated success story. But is this true?

New approach

Schmidt and Zimmermann have extensive data from archaeological sites in the whole of Europe are collected. They were looking for on a large scale for possible core areas of the settlement in the time of the so-called Aurignaciens in front of 42 000 and 33 000 years ago. In their analysis, the archaeologists of the Andes in a targeted regional with very large-scale data, a newly developed approach. From the so-called ethnographic analyses, especially the comparison with present-day hunter-gatherer societies, the average size of the group of about 40 people.

from This, the researchers to Schmidt calculated the absolute number of people. So a value of about 1500 people, with a lower limit of 800 and an upper limit of 3300. Not much for Central and Western Europe – so many people are born today in six minutes in the world.

The largest group lived in French caves

Only in five regions there was a permanently viable Population of 150 persons or more: in the North of Spain, southwest France, in Belgium, in Parts of the Czech Republic and in the valley of the Ur-Danube, in the Swabian Alb. In the southwest of France, with its karst is the largest group lived in caves with 440 people. The centers were around 400 kilometres away from each other, in between, large landscape areas, the goods only in the short term, seasonally, or not at all inhabited locations. This is a Europe-wide uniform pattern, the researchers write.

Apparently, the centres were networked, such as analyses of transported Stone artefacts, or flint raw materials show, from the people Sound then, tips, or scraper. The respective groups are used in spite of the large distances similar social and economic strategies to survive under the glacial climate conditions.

36 000 year-old painting: Popular Subjects were animals. Photo:

in addition to the core regions, there were areas, in which small groups of about 40 people were staying. This would not survive been able. These regions were, on average, about 200 kilometres from the main centres, and were probably visited only during certain times of the year. So the people adapted to different habitats. This strategy allowed density according to the researchers, despite the extremely small population to colonize Europe successfully.

group size of 150 people is the optimum

Even if regional populations became extinct repeatedly, is this System due to the high mobility, flexible adaptation to different natural, as well as the spaces to be very resilient, says Schmidt. "Much suggests that the human presence influences only the environmental, but also socio-cultural Patterns." Crucial to the success of the type, intensity, and persistence of connectivity over large distances.

Particularly interesting are the group sizes of the core regions. The British psychologist Robert Dunbar had already pointed out earlier that foragers in groups of a maximum of 150 people lived together. His conjecture: Our brain, specifically the cerebral cortex, sets limits in terms of the number of individuals with which an Individual's social contacts can maintain. The Dunbar number varies between 100 and 250, and also seems to apply to modern social networks.

Only in five regions there was a permanently viable Population.

In Europe, the population has increased in the Aurignacian epoch of the so-called Gravettian of around 2500 people, the number of viable core regions increased from five to nine. The network was larger and more branched, the spacing between the core regions remained at around 400 kilometres. Only towards the end of the Gravettian in front of around 27 000 years, the network is collapsed due to climate changes, says Schmidt. "We see a regional extinction of populations and the beginning of a reorganization." The old structures have collapsed and new networks emerged.

For one of the most dramatic events in the history of mankind, there is not such detailed analyses of the world's population. Some researchers believe that the human race stood in front of around 74 000 years ago on the verge of extinction, as in the Northern highlands of Sumatra, the volcano Toba erupted.

Maximum of 10 000 people survived the volcano eruption

probably The strongest Eruption of the past two million years, could, at least in the Northern hemisphere, the earth dramatically cooled. Population geneticists estimate that, at the time in the world to a maximum of 10 000 people had survived, maybe there were only 2800 individuals.

Controversial is whether the volcano was extinct in all the regions of the reason for the Almost. Researchers such as Eugene Smith, of the University of Nevada have sites single Fund, such as Pinnacle Point in South Africa was investigated. Smith found traces of the volcanic eruption, as he wrote last year in "Nature", but no changes in the Population due to the volcano. Perhaps South Africa was the last refuge of humanity – and the disaster took place in the Northern hemisphere.

The definitive ascent of man to the top of the food chain began as recently as 11 000 years ago, with the Settling down, with the advent of stock and exchange networks. Since then, the human population is increasing faster and faster. Currently around 7.6 billion people on the earth. And every year there are about 78 million more.

(editing Tamedia)

Created: 11.03.2019, 23:44 PM

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