Nature · 2
After coral polyps expel their symbiotic algae during a heatwave, why do they typically begin to starve?
Answer
The algae normally supply most of the coral's food through photosynthesis
Zooxanthellae algae living within coral tissue photosynthesize and pass most of the resulting nutrients to their coral host. Without this steady food source after expulsion, bleached corals are left to rely on limited feeding and often die if warm conditions persist.
💡 Did you know?
Coral polyps expel their algae partners during heat stress, then starve without them—bleaching is essentially a symbiotic breakup caused by warming oceans.
Other options people guess
- The algae normally shield the coral from predatory fish
- The algae normally help the coral secrete its skeleton
- The algae normally regulate the coral's reproductive timing
Topics
- symbiosis
- coral-reefs
- marine-biology
- climate
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