A biologist from the United States said?in Beijing on?Sunday that two-thirds of the world's species may disappear in the 21st Century and "a great majority" of them may be gone before they are even identified by human beings.

Peter Raven, president of the Missouri Botanical Garden, said in his keynote speech at the 23rd International Congress for Conservation Biology (ICCB) that species on the earth are disappearing at a rapid rate due to habitat destruction, climate change and a wide spread of invasive alien species caused by expanding human activities.

"Currently, several thousand species are lost every year," Raven said, "and very soon the number could rise to more than 10,000."

The 23rd ICCB, co-organized by the Society for Conservation Biology, the Chinese Academy of Sciences and the State Forestry Administration of China, opened here Sunday will last for five days. This is the first time the ICCB has been held in Asia. It attracted about 1,200 biological researchers from 74 countries.

China, thanks to its large territory, numerous mountain ranges and rich tropical ecosystems along the southern border, boasts about one-eighth of the world's total species of eukaryotic organisms, said Raven.

"But China's biodiversity is being destroyed at least as fast as in other parts of the world," he said.

To prevent the rapid loss of world species, Raven proposed that information on the species be collected and disseminated as fast and as much as possible to raise public awareness on wildlife protection.

He also called for expansions of parks and nature reserves and more cooperation within the international community to develop new technologies for maintaining biological sustainability, allowing a fair number of the population to live where they like and setting acceptable consumption levels for individuals.

(Xinhua News Agency July 13, 2009)