A call goes out for a new global effort to puzzle out humanity's ecological history over the last 50,000 years or more
|Scooped by Artur Alves|
"The putative start date for what scientists have begun to call the Anthropocene—a newly defined epoch in which humanity is the dominant force on the planet—ranges widely. Some argue that humans began changing the global environment about 50,000 years back, in the Pleistocene epoch, helping along if not outright causing the mass extinctions of megafauna, from mammoths to giant kangaroos, on most continents. Others date it to the emergence of agriculture some 7,000 years ago. The most definitive cases to be made coincide with the start of the industrial revolution and the dawn of the atomic age. The beginnings of burning fossil fuels to power machines in the 19th century initiated a change in the mix of atmospheric gases , and the first nuclear weapon test on July 16, 1945, spread unique isotopes across the globe.
There is little doubt from the archaeological record that humans have been altering ecosystems on a local scale for at least 50,000 years if not longer, but the extent of that alteration remains unknown. Recent work by ecologist Erle Ellis of the University of Maryland, Baltimore County, and others suggests that for at least 3,000 yearshunting, farming and burning have shaped most landscapes on the planet, based on computer models."