These tropical trees breathe at night to survive drought

Plants have evolved several ways to use sunlight to turn water and carbon dioxide into energy-rich sugars and oxygen (photosynthesis). But when water becomes scarce, that process can become much more difficult.

Researchers led by Wolfram Weckwerth at the University of Vienna have now uncovered how one especially water efficient form of photosynthesis (CAM) evolved in multiple ways within a single genus of tropical trees. By comparing the genomes of three Clusia species, the team traced how ancient genome duplication followed by extensive genetic reorganization helped produce different forms of CAM. The findings were recently published in Nature Communications .

A Photosynthesis Mystery Dating Back 200 Years

Around 1800, Alexander von Humboldt noticed something unusual while studying a tropical tree. He placed one of its leaves in water and found that, even in sunlight, it did not produce the oxygen bubbles he had observed before.