Hundreds of ancient earthworks resembling those at Stonehenge were built in the Amazon rainforest, scientists have discovered after flying drones over the area.
The findings prove for the first time that prehistoric settlers in Brazil cleared large wooded areas to create huge enclosures meaning that the ‘pristine’ rainforest celebrated by ecologists is actually relatively new.
The ditched enclosures, in Acre state in the western Brazilian Amazon, have been concealed for centuries by trees, but modern deforestation has allowed 450 to emerge from the undergrowth. They were discovered after scientists from the UK and Brazil flew drones over last year.
The earthworks, known by archaeologists as ‘geoglyphs’ probably date from around the year zero.
What would be even more interesting to know is how long does it take?
That is, remove man from any particular environment around here. How long does it take to go back to “normal”? Normal meaning pretty much how it was before any men turned up?
100 years is obviously too little time, but is 500 enough? 1,000? For example, say we just stopped farming the British uplands. How long before the ancient forests are back as George Monbiot recommends?