According to a new study, climate change could have played a major role in the development of ancient civilisations on the Indian subcontinent.
     Using high-resolution, precisely dated records of oxygen isotopes from stalagmite profiles in Sahiya Cave, in the foothills of the Himalayas near India's border with Tibet, Gayatri Kathayat and colleagues have shown the region is strongly influenced by changes in summer monsoon circulation and rainfall, making the stalagmites reliable records of past climate change. Combined with records obtained during a prior study, they form one of the most thorough documentations of summer monsoon variability over the last 5,700 years.
     Revealing drier conditions spanning multiple centuries beginning around 4,100 years ago, the team believes severe regional drought could have contributed to the decline of the Indus Valley cities, and the downfall of the Guge Kingdom in western Tibet around 1620 CE.
     The authors acknowledge that human factors could also have contributed to changes in ancient Indian civilisations, and believe future archeological and palaeo-climate studies are needed.

Edited from Popular Archaeology (13 December 2017)