In a study now published online in Nature Communications, researchers from Imperial College London and the Indian Institute of Technology Kanpur found and dated the remains of an ancient river known as the Sutlej, which once flowed through the Himalayan area. Research revealed that the river dried up around 8,000 years ago, a full 3,000 years before the development of the Indus Valley Civilization. The finding showed that the urban area was able to grow and thrive for several thousand years despite not having an actively flowing river nearby.
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But how could a major civilization have survived without a water source? The team determined that the "scar" the dried-up Sutlej River left captured water flow during monsoons, which may have acted as a water source for settlements in the area, Physreported.
The findings were significant, as they gave insight into how ancient civilizations rose and thrived. The previously accepted theory was that ancient civilizations needed an active water source nearby to thrive. Scientists thought that once a water source dried up, ancient people were forced to move on.
"We now know that, given the right conditions, valleys that have lost their rivers can still serve as a water source,” said coauthor Rajiv Sinha, from the Indian Institute of Technology Kanpur, Phys reported.