High attitude is a major environmental stress for humans because the air pressure is decreased and the extreme changes in climate from day to night. High attitude decreased air pressure making it difficult for human to take in oxygen and can lead to hypoxia. In serious cases, cerebral edema and pulmonary edema can develop which can lead to death very quickly.
Short-term adaptations
Increase in heart rate and breathing; pulse and blood pressure pump harder to get more oxygen.
Facultative adaptations
Acclimatization takes place; more red blood cells and capillaries are produced to carry more oxygen. Lungs increase in size to facilitate the osmosis of oxygen and carbon dioxide.
Developmental adaptations
Population in Tibetan villagers who lived about 15,000 feet showed to have 10 oxygen-procession genes not found in lowland populations. Population of Indians from the high mountain valleys in Peru and Bolivia has produced more hemoglobin in their blood and their lung expansion capability. There is an increased blood flow near the skin surface.
Cultural adaptations
Populations who lived in high altitude, a tool kit, control of fire, and protective clothing are important cultural adaptations. Mountain climbers on the other hand, use oxygen tanks to help for breathing when in high altitudes.
The benefits of studying human variation from this perspective across environmental clines are to understand the differences of people living in completely different settings and how or why they continued to live there. By studying these different stresses, we can better prepare ourselves if ever being faced with any of these stresses.
Using race to understand human variation of adaptations is not an accurate especially when compared to environmental influences. Observing how human adapt based on those environmental influences is much more accurate form of studying human variation.
