National Geographic : 2017 Apr
12,500 YEARS AGO EVOLVED TO LIVE AT HIGH ALTITUDES Until recently it was thought that our species had stopped evolving far in the past. Our ability to peer inside the hu- man genome has shown that in fact our biology continues to change to suit particular environments. Most of us feel breathless in high mountain air because our lungs must work harder to capture the reduced level of oxygen there. But Andeans have a genetically determined trait that allows their hemoglobin to bind more oxygen. Tibetan and Ethiopian populations independently adapted to their high elevations, showing that natural selection can take us on different paths to reach the same outcome: survival.