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More species threatened by extinction

27 October 2010 Last updated at 09:52 BST

One fifth of animal and plant species are under the threat of extinction, a global conservation study has warned.

Scientists who compiled the Red List of Threatened Species say the proportion of species facing wipeout is rising.

But they say intensive conservation work has already pulled some species back from the brink of oblivion.

Daniel Boettcher reports.