More than 9,000 tree species still undiscovered: Study
Washington, Feb. 1: Researchers estimate there are significantly more species of trees on Earth than currently known, with more than 9,000 species yet to be discovered, according to a study published on Monday.
“Estimating the number of tree species is essential to inform, optimise, and prioritise forest conservation efforts across the globe,” said the study, which was published in the US National Academy of Sciences journal PNAS and involved dozens of scientists. About 64,100 tree species have already been identified.
But according to the study, which is based on a more complete database and uses a more advanced statistical method than previous ones, the total number of tree species is about 73,300 — 14 per cent more. That means about 9,200 species have not yet been discovered.
Overall, the study said that “roughly” 43 per cent of all tree species are found in South America, followed by Eurasia (22 per cent), Africa (16 per cent), North America (15 per cent) and Oceania (11 per cent).
Half to two-thirds of all known species are found in tropical or subtropical rainforests on five different continents, the researchers estimated.
A large proportion of the species yet to be discovered should therefore be found in these same regions, where fewer surveys are conducted.
Additionally, nearly a third of the world’s tree species are scientifically classified as rare, with low populations in limited regions. These species are therefore more vulnerable to the threat of extinction.
Only 0.1 per cent of species are found in all five of the regions identified by the study.
South America also has the highest proportion of endemic species, or species only present on that continent, at 49 per cent.
“These results highlight the vulnerability of global tree species diversity,” the study authors said. —