Until now, the world has lacked a system for tying together knowledge about the diversity of life -- most observations are local, such as of butterflies in part of the Amazon rainforest or of rice growth in Indonesia.

"We haven't had the capability to knit it all together," Woody Turner, an earth scientist at NASA which is helping put together the global network that will include research institutes and governments, told Reuters.

He said the network would help plug gaps since the time of 19th century naturalists such as Charles Darwin, who published the theory of evolution in 1859 based partly on observations of

The new monitoring network "will advance international efforts to rescue the world's vanishing biological diversity," the Group on Earth Observations (GEO), backed by more than 70 governments, said in a statement of the Potsdam plan.

UN reports say the world may be facing the worst spate of extinctions since the dinosaurs vanished 65 million years ago due to human activities such as emissions of greenhouse gases. a tiny fraction of life in the Galapagos.

A UN Earth Summit in 2002 set a goal of slowing the rate of biodiversity loss by 2010 but set no baselines for judging success or failure.

DINOSAURS

"The lack of comprehensive information about the world's biological resources continues to undermine the efforts of policymakers and managers to set priorities," GEO said. GEO has prompted the new network with calls for better monitoring.

Initial monitoring by the network would "not be every species on earth. We have to bring it down to a few thousand," said Anne Larigauderie, head of the Diversitas Secretariat in Paris which groups biodiversity experts.

Well-known species such as tigers, lions, whales or dolphins could make the initial list and also "species that play a key functional role", she told Reuters.

Such species could include crops such as rice or wheat, insect pollinators or large trees that soak up carbon dioxide, the main greenhouse gas. Diversitas and NASA will lead work to build the network, backed by GEO.

Turner said satellites, for instance, could add a new dimension to local studies of species.