Forests are being felled, vast areas of countryside are being buried under concrete and beautiful marine environments are being destroyed. At the root of all these problems lies the raging consumption of energy and other resources that started in Europe and America - and is now spreading like a disease all around the world. Many people feel that unless we cure ourselves of this need to consume, we will kill the Earth - and ourselves. The mountain gorilla is just one of millions of animal and plant species threatened with extinction by the loss of their natural habitats. Many species have become extinct naturally in the past, but they are now becoming extinct 400 times more quickly.
Ecologists fear that the loss of variety leaves nature very vulnerable to any catastrophe.
But even in the industrialized world, where drinking water is relatively healthy, many rivers are badly polluted by chemicals and untreated raw sewage. Huge spillages of oil from supertankers can do great damage to seabirds and other creatures. Wrecks may release dangerous chemicals as they gradually corrode. Nuclear waste still lies dumped on the sea bed. Nuclear power stations dump radioactive liquid waste straight into the sea.