The benefits reaped from biodiversity can be found everywhere. The rosy periwinkle, a plant found only in the Madagascar rain forests, has proved of enormous value in combating childhood leukaemia. The bark of the Pacific yew in the northwestern United States is being used to combat certain forms of cancer. More than a quarter of all prescriptions in modern Western medicine contain active ingredients extracted from wild plants. Every variety of wheat grown in Canada contains genes introduced from as many as 14 other countries.
Habitat destruction is another major threat to biodiversity.
It is also lost through over-harvesting, chemical pollution and the inappropriate introduction of foreign plants and animals. Climate change threatens to accelerate the current destruction. The ratification that made the Convention international law came from Mongolia on 30 September. By mid-December 167 States had signed the Convention, including the ratifiers. Many Governments that have signed are in process of securing ratification, including the United States and countries of the European Union.