Background Info

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 strontium analysis of teeth, what it can tell us about an individual, and the specific results uncovered by Aldenderfer's team. Strontium is an element that occurs naturally in the earth and is absorbed into the bodies of infants through water and mother's milk. Today, scientists can determine exact strontium levels of almost any place on Earth.

The strontium levels of Upper Mustang have been documented, and Aldenderfer's team has been documenting strontium in local species like mice and snails. This helps them to determine the exact variables for the mortuary cave locations.



What isotope is Dr. Mark Aldenderfer trying to find? Where is he looking for it, and why?

Show Answer

Dr. Aldenderfer is looking for strontium in the teeth of remains of ancient people buried in caves in Upper Mustang, Nepal. Strontium comes from groundwater a person drinks, and mothers pass it on to their infants.


What surprising discovery does Dr. Aldenderfer make?

Show Answer

Strontium analysis reveals that males were indigenous to, or originated, in this high region. The women, who had different strontium levels, were probably from the lowlands.


What are the implications of this discovery?

Show Answer

The discovery indicates that this area was a well-traveled crossroads. The strontium analysis also implies that women had to adapt to the high, cold climate of Upper Mustang.

For Further Exploration


Term Part of Speech Definition Encyclopedic Entry



science of the origin, development, and culture of human beings.

Encyclopedic Entry: anthropology



person who studies artifacts and lifestyles of ancient cultures.

field work


scientific studies done outside of a lab, classroom, or office.

Encyclopedic Entry: field work



atom with an unbalanced number of neutrons in its nucleus, giving it a different atomic weight than other atoms of the same element.



the study of fossils and life from early geologic periods.

Encyclopedic Entry: paleontology


Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.


Hannah Herrero


Caryl-Sue, National Geographic Society
Anne Haywood, National Geographic Society

National Geographic Explorer

Dr. Mark Aldenderfer, Archaeology

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