The mystery of Skeleton Lake
Remains were deposited 1000 years apart. Biplab Das reports.
New research has finally shed some light on the origins of several hundred people who died mysteriously on the edge of India's Skeleton Lake.
Skeletal remains have been found scattered around the shores of what is officially Roopkund Lake, nestled deep in the Himalayas at more than 5000 metres in the state of Uttarakhand.
Several hypotheses have been suggested over the years to explain where they came from, but given the nature of the site it has been difficult to be sure - until now.
Analysing the remains of 38 individuals and comparing their mitochondrial DNA with that of modern people across the globe, international researchers found that the remains belonged to three genetically distinct groups from Asia and the Mediterranean.
And they died at separate times: one group 1200 years ago, the other only about 200 years ago.
To get their answers, the researchers, led by David Reich from the Harvard Medical School, US, and Niraj Rai from the Birbal Sahni Institute of Palaeosciences in India, measured the levels of carbon and nitrogen isotopes in femur bone collagen. This reveals what people ate in the last decade of their lives and where they come from.
Dietary habit, supported by the genetic analyses, suggests that 23 individuals were close to modern South Asian people, one came from East Asia, and 14 were close to people living in present-day Greece
Radiocarbon dating, the researchers note, further reveals that the people of South Asian origins arrived near the lake around 800 CE – though the remains were deposited in more than one event – while those from the Mediterranean arrived around 1800 CE.
The lake is not on any major trade route, but on a present-day pilgrimage route, with evidence of such a route found in inscriptions in nearby temples that date back to between eighth and tenth centuries.
Thus the lake people, mostly middle-aged unrelated men and women, were probably pilgrims, the study suggests.
And what could have killed them?
The researchers found no signs of pathogen in their bones, except compression fractures in three individuals. Some unhealed broken fragments attached to the skull indicate that the injuries occurred at or near the time of death or could have caused them.
Hailstones as large as cricket balls regularly hit the area around Roopkund and this may well have been the cause, they suggest.
The research is published in the journal Nature Communications.