Many of the ways that Tibetans make money are dependent on mountain ecosystems, such as herding livestock or harvesting local plants and fungi. As the seasons change, the Tibetans move up and down the mountain. They move down when it gets colder in winter, and up when it gets warmer in summer. This movement allows them to rotate through fresh green pastures for their livestock and provides new areas to search for a fungus called catepillar fungus, which is used in traditional Chinese medicine. So, the mountains and seasonal changes are important for Tibetan livelihoods.
Lack of oxygen at high altitude can make it difficult to physically live in the mountains. Your body needs oxygen to function, so having less of it in the air for you to breathe in can give you shortness of breath, headaches, tiredness and make you sick. Eventually, your body finds ways to compensate for this. For example, you may breathe faster to get in more oxygen or your body may produce more red blood cells that carry the oxygen you breathe into your heart and lungs. But it takes a while to adapt. For researchers from low altitude (like me!), altitude sickness can make our work even harder. It takes a couple of days for my body to adjust to the altitude and make all the changes necessary so that I can physically function. Even then, I still don't feel 100% until at least ten days into sampling. However, the Tibetans we work with don't have this problem, because they have adaptations to high-altitude "built" into their bodies.
