十万个为什么·科学阅读30篇（4）

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为什么某些真菌仅在黑暗中产生发光菌丝？

Species like Neonothopanus gardneri emit soft green light from their mycelial networks exclusively at night.
A luciferin-luciferase reaction powers this glow, but the enzyme only activates when light-sensitive proteins detect darkness.
Blue-light receptors suppress bioluminescence during daylight by blocking transcription of key luminescence genes.
This circadian regulation conserves energy and avoids attracting daytime predators like birds or insects.
The glow attracts nocturnal arthropods that disperse spores while feeding on fungal tissue or secretions.
Researchers found that constant light exposure stops glowing within 48 hours—even if nutrients remain abundant.
Fungal bioluminescence differs from marine organisms because it requires oxygen, luciferin, and ATP all simultaneously.
Its spectral peak at 490 nm matches the visual sensitivity of many night-active insects perfectly.
Field studies show higher spore dispersal rates under moonless nights compared to full-moon conditions.
This adaptation highlights how evolution fine-tunes biological light emission for ecological timing and function.