Three Parallel Rivers area is reputed to be the "Biological Gene Bank of the World." Because it was not covered by the Quaternary glaciers and most mountains lie from north to south, the area has become a main passage and sanctuary for biological species of the Eurasian Continent. Although the area covers no more than 0.4% of Chinese territory, it contains more than 20% of higher plants and 25% of animal species of the country, including 77 species of endangered animals like the Yunnan golden monkey, the antelope, the snow leopard, the Bengali tiger, and the black-necked crane.