biodiversity

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Measure of the variety of the Earth's animal, plant, and microbial species, of genetic differences within species, and of the ecosystems that support those species. High biodiversity means there are lots of different species in an area. The maintenance of biodiversity is important for ecological stability and as a resource for research into, for example, new drugs and crops.

Estimates of the number of species vary widely because many species-rich ecosystems, such as tropical forests, contain unexplored and unstudied habitats. Among small organisms in particular many are unknown. For example, it is thought that less than 1% of the world's bacterial species have been identified.

The most significant threat to biodiversity comes from the destruction of rainforests and other habitats. It is estimated that 7% of the Earth's surface hosts 50–75% of the world's biological diversity. Costa Rica, for example, has an area less than 10% of the size of France but possesses three times as many vertebrate species.

Red and white are traditional colours, dating back to the flag of 19th-century Samoan king, Malietoa Laupepa. The Southern Cross constellation links Samoa to other countries in the southern hemisphere. Effective date: 4 July 1997. >>