Just 227 tree species dominate Amazon

Researchers were surprised to find that such a small proportion of species dominated the Amazon .
Despite being home to about 16,000 tree species, just 227 "hyperdominant" species account for half of Amazonia's total trees, a study suggests.

An international team of researchers found that the region was, in total, home to an estimated 390 billion trees.

Writing in Science, they added that the rarest 11,000 species made up only 0.12% of tree cover.

However, they added that the new data could help unlock ecological secrets held by the biodiversity hotspot.

The results were based on a survey of 1,170 plots and half-a-million trees across the six-million-square-kilometre area, often described as the lungs of the world.

The authors said that the underlying cause of the hyper dominance of the 227 species, which accounted for 1.4% of the estimated number of species in the region, remained unknown.

"We knew that, normally, a few species dominate ecosystems, but if you have a system that has 16,000 tree species but just 227 make up half of the trees, that was pretty surprising even for us," said lead author Dr Hans ter Steege from the Naturalis Biodiversity Center in the Netherlands.

He told the Science podcast: "We don't really know why these species are so incredibly dominant because they do not have any particular ecological feature that stands out."