Yet we are in the midst of destroying large parts of that system. A burgeoning human population expected to reach 10 billion by 2050-is eliminating or altering natural habitats all over the globe, with devastating consequences to species diversity. We risk losing one-quarter of the world's species in the next 20 to 30 years. Many species not on the verge of extinction are being diminished in numbers. As subspecies and diverse forms are wiped out, species are also losing internal genetic variability, which threatens their adaptability and ultimate survival.
Some people argue that extinction is a natural process, that species have always come and gone.
But today species are vanishing from the Earth at a rate of one a day, surpassing even the mass extinctions 6 million years ago when the dinosaurs perished. The cost of species loss Our lives depend in myriad ways on the Earth's great diversity of species, subspecies and ecosystems. Collapsing biological diversity threatens our food supplies, medicinal advances, the development of new industrial products and many other practical needs. We have made great advances in breeding crops for greater productivity and for resistance to diseases, pests and drought. It couldn't have been done without the genetic traits of wild relatives of crop plants.