In the long chain of human DNA， there are around 100，000 genes， which record our ancestors code. Nature took billions of years to develop such voluminous， delicate and complex genes， so that each species is a unique gene pool.

China is among the countries possessing the richest biodiversity in the world， not only extremely rich in species and ecosystem types， but with highest uniqueness. Our country has over ten thousand kinds of endemic species. Fir， silver fir， ginkgo and dove all belong to Chinas unique and rare relict plant. However， the extinction of any one species will take away its unique genes. As the approach of the "International Biodiversity Day" on May 22， "Knowledge is Power" magazine has planned this special topic in the hope to get more attention on the conservation of biological diversity. As we enjoy the selfless gifts of nature， should we do something for mother earth？