The 2.2% of the most common tree species cover 50% of the forests

A collaborative study of 356 international scientists has identified almost identical patterns of tree diversity in the tropical forests of the planet, regardless of the continent, and an important key: only 2.2% of tree species, the most common, represent 50% of all trees.

The research, whose conclusions are reported today in the magazine Nature, is the result of the analysis of more than one million trees of 8,493 species in 1,568 tropical forest areas in Africa, the Amazon and Southeast Asia.

Scientists have seen that on each continent there is the same minimum proportion of those common species that occupy most of the forest and, however, many rare species that only represent a small fraction of the forest mass.

They estimate that 1,053 common species represent half of the 800 billion trees in the planet’s tropical forests; 6,500 slightly less common species make up the 40% of the forest and 39,500 rare species represent the 10% remaining.

From the ecological point of view, the discovery reveals that common species constitute a kind of “shortcut” so that scientists can understand a forest as a whole, a relevant issue for science since forest masses develop vital functions, including absorbing and storing CO2.

“Our conclusions reveal that if we focus on knowing the most common tree species, we will probably be able to predict how the entire forest will respond to today’s rapid environmental changes.”says Declan Cooper, one of the directors of the study, affiliated with University College London.

However, the fact that the pattern of species prevalence is the same in very different forests is really “amazing”, Cooper adds.

Furthermore, while humans have inhabited the forests of Southeast Asia and Africa for more than 40,000 years, humans began to inhabit the Amazon about 20,000 years ago.

In terms of contemporary climatology, African forests have drier and colder weather than the other two tropical forest regions.

Researchers believe that the fact that there are identical patterns of biological diversity in such different forests implies that there may be some kind of common mechanism that may govern forest formation, and they will continue research to verify its existence and understand how it works.