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Environmental Adaptation
Populations residing in altitudes above 2,500 meters have adapted to to their hypoxic environments. Chronic Hypoxic Ventilatory Response is set of adaptations found among most human populations historically native to high-altitude regions, including the Tibetan Plateau, the Andean Mountains, and the Simian Plateau. Up to 140 million people in total reside in such areas, although not all possess these adaptations. Populations that have permanently settled in high altitude locations show virtually no reaction to acute hypoxia. Natives of the Andes and the Himalayas have been shown to develop adaptation to hypoxia from birth to neonatal years in the form of larger lungs and greater gas exchange surface area. This response can be attributed to genetic factors, but the development of the resistance to acute hypoxia is highly affected by when the individual is exposed to high altitude(1); while genetic factors play an indefinite role in a person’s hypoxic ventilator response, because long term migrants do not show reduction in their reactions of high altitude even after living in high altitudes in long term, the discrepancy suggests that reaction to HVR is the combination of environmental exposure and genetic factors.