Indus era 8,000 years old

Scientists from IIT-Kharagpur and Archaeological Survey of India (ASI) have uncovered evidence that the Indus Valley Civilisation is at least 8,000 years old, and not 5,500 years old, taking root well before the Egyptian (7000BC to 3000BC) and Mesopotamian (6500BC to 3100BC) civilisations. What's more, the researchers have found evidence of a pre-Harappan civilisation that existed for at least 1,000 years before this.
The discovery, published in the prestigious `Nature' journal on May 25, may force a global rethink on the timelines of the so-called `cradles of civilisation'. The scientists believe they also know why the civilisation ended about 3,000 years ago -climate change.
“We have recovered perhaps the oldest pottery from the civilisation. We used a technique called `optically stimulated luminescence' to date pottery shards of the Early Mature Harappan time to nearly 6,000 years ago and the cultural levels of pre-Harappan Hakra phase as far back as 8,000 years,“ said Anindya Sarkar, head of the department of geology and geophysics at IIT-Kgp.
The team had actually set out to prove that the civilisation proliferated to other Indian sites like Bhirrana and Rakhigarrhi in Haryana, apart from the known locations of Harappa and Mohenjo Daro in Pakistan and Lothal, Dholavira and Kalibangan in India. They took their dig to an unexplored site, Bhirrana -and ended up unearthing something much bigger. The excavation also yielded large quantities of animal remains like bones, teeth, horn cores of cow, goat, deer and antelope, which were put through Carbon 14 analysis to decipher antiquity and the climatic conditions in which the civilisation flourished, said Arati Deshpande Mukherjee of Deccan College, which helped analyse the finds along with Physical Research Laboratory, Ahmedabad.
The researchers believe they know why the civilisation vanished. Their study revealed that monsoon became progressively weaker after 7,000 BC but, surprisingly, the civilisation did not disappear. The Indus Valley people were very resolute and flexible and continued to evolve even in the face of declining monsoon.
The people shifted their crop patterns from large grained cereals like wheat and barley during the early part of intensified monsoon to drought-resistant species of small millets and rice in the latter part. As the yield diminished, the organised large storage system of the Mature Harappan period gave way to smaller, more individual household-based crop processing and storage systems that acted as a catalyst for the de-urbanisation of the Harappan civilisation rather than an abrupt collapse, they say.