The 2019 Harvard DNA study that broke the single-hailstorm theory.
For 80 years, every guidebook said Roopkund was a single 9th-c. mass-casualty hailstorm. A 2019 genome study of 38 skeletons (Nature Communications) found three genetically distinct groups deposited across 1000 years — destroying the single-event story most trekkers still believe.WHY NOBODY KNOWS
Researchers at Harvard, the Max Planck Institute and the CCMB Hyderabad sequenced 38 of the ~700 skeletons. The findings, published Aug 2019: 23 individuals had South-Asian ancestry and radiocarbon-dated to ~800 CE, but with evidence of *multiple deposition events* (not one); 14 individuals had eastern-Mediterranean ancestry — most closely related to people from Crete and Greece — and dated to ~1800 CE; one had Southeast-Asian ancestry, also ~1800 CE. The Mediterranean cluster is unexplained — no plausible historical record places 14 Greeks at 4500m in Garhwal in the 18th c. The hailstorm theory still works for some 800 CE skulls (dorsal-only cranial fractures consistent with falling ice), but cannot explain the 17-18th c. group.
