- March 12, 2015
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The Anthropocene, a new geological period that marks the “old man” began in 1610, according to a new study published in the journal Nature.
Scientists believe that the arrival of Europeans to the Americas had an unprecedented impact on the planet and, therefore, this moment can be considered as the beginning of a new era.
Others, however, consider that the industrial revolution or the first nuclear tests should mark the beginning of the Anthropocene.
And some believe that the exact date of a new era can only be determined thousands or millions of years later.
But meanwhile, an international team of scientists found . analyzing the evidence
The result of these deliberations will be announced next year
See also:. 2016, the year that could change time
Looking for a “marker”
Geologists divide the history of Earth into segments that reflect times of significant changes that may be the result of continental movements, the impact of a large asteroid or a profound change in climate.
Currently, we are formally in an era called the Holocene that began over 11,500 years ago after the end of the last Ice Age.
But now , scientists argue that humanity has changed the planet dramatically.
In order to establish the beginning of this new phase geologists are looking for a clear signal that they describe as a “marker” that must be recorded rocks, sediments or ice.
“We seek these markers, a real moment in time in which you can show a record of when it changed the entire Earth,” says Mark Maslin, a professor at University College . London and co-author of the study
“If you take into account the whole wonderful geological time scale, almost all have defined limits that way”
See also:. What rocks and humanity will become fossils?
From here to there
The study suggests that one of these markers located the start of the Anthropocene in 1610.
According to the researchers, the arrival of Europeans to America a hundred years ago began a major global transformation.
“Global trade after that time caused a transfer of species,” says Simon Lewis, co-author of the Univesity College London .
“Corn Central America began to be cultivated in southern Europe, Africa and China. Potatoes are grown in South America UK, Europe and China.”
Corn A. Central began to be cultivated in southern Europe, Africa and China . Potatoes were grown in South America R. Kingdom, Europe and China. The species also traveled in the opposite direction. A. Wheat reached North and sugarcane A. South … a real mix of species worldwide
“The species also traveled in the opposite direction. The wheat arrived in North America and sugarcane in South America … a real mix of species around the world.”
“We saw these species jump continents, implying a geological unprecedented impact sent to Earth on a new evolutionary path.”
The ancient pollen found in sediments is a record of these changes, but the team believes there is another marker is linked to deadly diseases who came to America from Europe.
“About 50 million people died (in the Americas) and most of this people were farmers, “explains Lewis BBC News
.” And in these fields grew back the original vegetation. “
” tropical dry forests and savannas Close half of the dry weight of a carbon shaft is therefore all vegetation growing absorbed was sufficient carbon from the atmosphere for a sharp drop in the global carbon dioxide concentration occur and this can be seen in the records of the cores ice “.
” This marks us exactly the start of the Anthropocene in 1610, when the point is recorded lowest CO2 records from ice cores that time. “
Nuclear testing
Another possible start, the researchers say, could be 1964, when a ban put an end to nuclear testing in the 40, 50 and early 60s.
The increase in radioactive carbon in the atmosphere as they conducted the tests was followed by a sharp drop after completion. This offers another marker that could be taken as a turning point.
However, while this signal is very accurate, radioactivity is not related to any other major change in that time, Maslin says.
(The study raises some) fascinating ideas. Certainly the group’s discuss
“A mid-60s there was a big change around the planet we call ‘great acceleration’, with an increasing population of 2% per year, unprecedented changes in agriculture and food production, but the score is not linked to it in any way. “
According to Jan Zalasiewicz, a researcher at the University of Leicester in the UK, who heads the working group on the Anthropocene, the study is interesting and raises some “fascinating ideas.”
” Certainly the group discuss them, “he told the BBC.
” It is a positive addition to the whole debate about the Anthropocene and the growing number of suggestions on when to start “.
“The proposal for 1610 clearly reflects an important historical event, but needs more evidence.”
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