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Biodiversity means the rich variety of life forms in nature. GEO warns us that many of the world’s different plants and animals are under severe threat of extinction. Many species are lost already.

An ecosystem is a place where nature creates a unique mix of air, water, soil and a variety of living organisms to interact and support each other. Destroy these ecosystems and we are destroying ourselves. Deforestation, overfishing, over-hunting, forest fires, pollution and modern agricultural practices all contribute to the loss of habitat. Cutting roads and railways through habitats blocks natural migration and feeding routes.
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Foundation for Global Peace and the Environment

Living organisms are made up of cells. Scientists have found a way to copy, or clone, the information, or genes found in cells to make new plants and animals. But no one knows if it is totally safe to take genes from one species and add them another. Well-known examples of genetic manipulation include Dolly the sheep – the first cloned mammal, and adding the genes of a toad or a spider to vegetables.

Scientists have recorded 1.75 million species on our planet and estimate another 5 to 100 million unrecorded species! The educated guess stands at 12.5 million.

Exotic species are animal and plant species that find themselves outside their native habitat. These species cause changes to the ecosystem and sometimes destroy other species native to that ecosystem. For example, zebra mussels came from Europe to the Great Lakes of North America in the ballast of ships. They spread like a plague in the waterways of the continent, attaching themselves to existing mussels and killing them. Breeding quickly, they clog up hydro-electric generators, encrust the hulls of boats and erode pipes in water treatment plants.

A species is said to be extinct when it has not been seen for over 50 years. Dinosaurs became extinct 65 million years ago but, in the last 50 years, more animals and plants have become extinct, because of hunting and loss of habitat. Globally, many hundreds of species will face extinction in a very few years without intensive conservation, education and environmental management and policy-making.

web site editor: webmaster@grida.no Last update: March 2000