More than 100 researchers have collaborated to classify the world's tropical forests according to their evolutionary history, a process that will help researchers predict the resilience or susceptibility of different forests to global environmental changes.
The Amazon Rainforest [Credit: © Stéphane Bidouze/Fotolia] |
The study was led by Ferry Slik, an associate professor at the Universiti Brunei Darussalam in Brunei. Janet Franklin, a distinguished professor of biogeography at the University of California, Riverside, coordinated the interpretation and reporting of the data, which is publicly available as an open access article.
Franklin said the new classification scheme's value comes from the inclusion of ancestral information about the tree samples (gleaned from DNA analyses), rather than the "snapshot" of tree biodiversity that is obtained from recording a plant's species.
A phylogenic classification of the world's tropical forests revealed five major regions [Credit: UC Riverside] |
The study revealed five major tropical forest regions: Indo-Pacific, Subtropical, African, American, and Dry Forests, which are found at the boundaries between tropical and dry climates.
The study also showed the evolutionary relationships between the forests. One surprising finding was that tropical forests in Africa and South America are closely related, with most of the differences between them occurring within the last 100 million years.
UC Riverside's Janet Franklin conducting field work in a tropical dry forest in The Bahamas [Credit: UC Riverside] |
Researchers also found that related subtropical forests exist in two distinct regions: East Asia and Central/South America. "These regions share the same temperate climate and, even though they are not geographically close, their forests share common ancestors, which is a bit of a mystery," Franklin said. "However, it may be that we are actually looking at remnants of the once extensive tropical forests that ranged from North America all the way to Europe and Asia. When Earth's climate cooled down these forests mostly disappeared, but parts seem to have survived in Asia and America."
The researchers hope an understanding of the diversity and composition of the tropical forests will help them anticipate region-specific responses to global environmental change.
"Different forests may be more vulnerable or resilient to climate change and deforestation, so if we understand the similarities and differences between forests it will help inform conservation efforts," Franklin said.
Source: University of California - Riverside [February 05, 2018]