Because of Tibet's cold weather, the men and women wear thick long dresses (chuba's). The men wear a shorter version with pants underneath. The style of the clothing varies between regions. Nomads often wear thick sheepskin chuba's.
The Tibet Paleolithic Project is studying the Stone Age colonization of the plateau, hoping to gain insight into human adaptability in general and the cultural strategies the Tibetans developed as they learned to survive in this harsh environment.
The ability of Tibetans to function normally in the oxygen-deficient atmosphere at high altitudes - frequently above 4,400 metres (14,000 ft), has often puzzled observers. Recent research shows that, although Tibetans living at high altitudes have no more oxygen in their blood than other people, they have 10 times more nitric oxide (NO) and double the forearm blood flow of low-altitude dwellers. Nitric oxide causes dilation of blood vessels allowing blood to flow more freely to the extremities and aids the release of oxygen to tissues. What is not yet known is whether the high levels of nitric oxide are due to a genetic mutation or whether people from lower altitudes would gradually adapt similarly after living for prolonged periods at high altitudes. en.wikipedia.org/wiki/Tibetan_people
