Tropical Trees Use Night Breathing to Save Water
Research shows tropical trees evolved distinct water-saving strategies through ancient genetic changes, not a single mutation.
Key points
- Tropical trees evolved CAM photosynthesis through ancient genome duplications and long-term genetic reshuffling.
- This method allows trees to keep pores closed during the day to conserve water while storing carbon dioxide at night.
- Researchers compared three Clusia species to understand how different water-saving strategies developed within one genus.
Researchers at the University of Vienna explain how tropical trees survive drought. They breathe at night to save water during the hot day.
This strategy, called CAM photosynthesis, allows trees to keep their pores closed in sunlight. It prevents water loss while they store carbon dioxide.
Ancient genetic changes drove new strategies
The team studied three types of Clusia trees. They found that CAM did not evolve through one simple change.
Instead, ancient genome duplications happened millions of years ago. Over time, these extra genes were reshuffled and modified.
This process created different ways to handle carbon dioxide. Some trees use strong CAM, while others use hybrid methods.
Nighttime breathing reduces daytime water loss
Normal plants open tiny pores called stomata during the day. This lets in carbon dioxide but releases water.
CAM trees keep these pores closed while the sun is out. They absorb carbon dioxide at night and store it as acid.
This schedule is vital for survival in dry conditions. It minimizes evaporation when temperatures are highest.
Findings offer clues for future crops
The study was published in Nature Communications. It details how genetic reshuffling affects metabolic pathways.
