The Himalayas contain many unique and ancient cultures. Recently, a team of researchers and mountaineers led by archaeologist Dr. Mark Aldenderfer began unraveling mysteries surrounding peoples who lived thousands of years ago in the caves of Nepal's Upper Mustang region.

Aldenderfer led a 20-day expedition to the Upper Mustang to explore mysterious communal graves discovered in the 1990s. The skeletons and burial artifacts were found in caves on the sides of cliffs. To identify possible burial sites, Aldenderfer and his team, including bioarchaeologist Dr. Jackie Eng and seven-time Everest climber Pete Athans, combed the region for deep caves on the brink of collapse. The bones that Aldenderfer's team collected, thought to be the mysterious Membrak people, were then cleaned, pieced together, and analyzed.

This video is about scientists re-curating scientific finds 20 years after they were discovered. Technology has changed, and now, rather than testing for DNA in the marrow of leg bones, scientists tend to search for DNA using teeth. Why are teeth more reliable? Why do scientists test for DNA in the first place? The video helps answer these questions, as well as provide scientists with dates procured through carbon dating.

The Himalayan mummies studied in this video are naturally mummified corpses, not mummies in the Egyptian sense where the deceased are embalmed in a complex series of rituals and procedures. The Himalayan mummies were naturally preserved by the dry mountain air and protection of the caves in which they were buried.