Evolution in Action

Melanin, sickle-cell anemia resistance, lactose tolerance, and now blood chemistry and mountain sickness:

Scientists Cite Fastest Case of Human Evolution: Tibetans live at altitudes of 13,000 feet, breathing air that has 40 percent less oxygen than is available at sea level, yet suffer very little mountain sickness. The reason, according to a team of biologists in China, is human evolution.... Comparing the genomes of Tibetans and Han Chinese, the majority ethnic group in China, the...