How climate change ended world’s first great civilisations
David Keys
Monday, 3 March 2014
The world’s first great civilisations appear to have collapsed
because of an ancient episode of climate change – according to
new research carried out by scientists and archaeologists. Their
investigation demonstrates that the Bronze Age ‘megacities’ of
the Indus Valley region of Pakistan and north-west India declined
during the 21st and 20th centuries BC and never recovered –
because of a dramatic increase in drought conditions. The
research, carried out by the University of Cambridge and India’s
Banaras Hindu University, reveals that a series of droughts
lasting some 200 years hit the Indus Valley zone – and was
probably responsible for the rapid decline of the great Bronze
Age urban civilisation of that region.
It’s now thought likely that the droughts at around that time
were partly responsible for the collapse not only of the Indus
Valley Civilisation, but also of the ancient Akkadian Empire,
Old Kingdom Egypt and possibly Early Bronze Age civilisations
in Greece. “Our evidence suggests that it was the most intense
period of drought – probably due to frequent monsoon failure
– in the 5000 year-long period we have examined,” said
University of Cambridge Palaeoclimate scientist Professor
David Hodell. The scientists studying the collapse of the Indus
Valley Civilisation obtained their new evidence from a dried-up
lake bed near India’s capital New Delhi which is just 40 miles
east of the eastern edge of the Indus Valley Civilisation.
The Indus Valley ‘megacities’ – some with populations of up
to 100,000 – rapidly declined. Populations shrank and the old
urban civilisation, which had lasted 500 years, collapsed.
“Archaeologists get an opportunity to investigate how ancient
populations responded to climatic and environmental change,”
said University of Cambridge archaeologist, Dr. Cameron Petrie.
“For the Indus populations, it looks as though living in large
groups became untenable, and it was much more sustainable to
live in smaller groups. This is of course a huge simplification
of a complex process, but this transformation is the underlying
dynamicˮ.
(www.independent.co.uk. Adaptado.)
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