Are the Sherpas and other highland peoples physiologically different from the
rest of us?
Dr. Cynthia Beall of Case Western Reserve University and Physical
Anthropology Advisor to the MacGillivray Freeman Films Everest IMAX/IWERKS
film, postulates that there may be a genetic factor involved in Sherpa strength
at altitude: "The Everest climbers must not only exert great physical effort
to climb the mountain, but do so while under tremendous hypoxic stress. This
stress is not something that can be mitigated in the way, for instance, that we
would put on extra clothes when we are cold. We must adapt physiologically.
How the Sherpas do this more effectively than others has been a puzzle to
anthropologists and physiologists, and we don't really have the answer. There
is evidence of a gene that allows their blood to carry more oxygen, but there
are other factors that affect this, as well."
Sherpas have played quiet but critical roles in Everest achievements. From the
beginning of their involvement with high altitude mountaineering, Sherpas have
paid a disproportionately high price in life and limb. In 1922 seven Sherpa
porters were buried under an avalanche on Everest's North Col. In the first
seventy years of Everest activity, 43 Sherpas were killed, more than a third of
the total deaths in that period. Even this year, on the south side of Everest,
two of the three evacuations from the mountain thus far—due to serious injury—were Sherpas. Because of their contribution to route fixing and ferrying
supplies, they find themselves exposed to the extreme risks of high mountain
climbing more frequently than their employers.
On our way up to Base Camp, we passed by a sacred site in the Khumbu valley, a
testament to the Sherpas that have lost their lives on the surrounding peaks.
Dozens of memorial chortens, each commemorating a death on the nearby
mountains, line a ridge that looks out on a 360° view of snow-covered
peaks. Although history has recorded their deeds as mere footnotes to
greatness, it is the Sherpa contribution and effort that has been the backbone
of most expeditions on Everest.
Liesl Clark, NOVA Online's producer and writer, joined the expedition up to Base Camp.
Audrey Salkeld of Clevedon, England is one of the world's premier
Everest historians and photo researchers. Her photo editing credits include
Everest: The Ultimate Book of the Ultimate Mountain and Everest: The
Best Writing and Pictures from Seventy Years of Human Endeavour.