longfin damselfish mysid shrimp algae fertilization

Damselfish protect shrimp that fertilize their algae

Longfin damselfish guard patches of algae on coral reefs. They allow small mysid shrimp to live there because the shrimp's waste fertilizes the algae. The fish get better-growing food, while the shrimp get protection from predators.

The Dead Sea’s surface has shrunk

About 33%

The Dead Sea’s surface had shrunk about 33% since the 1960s. Water diversion from the Jordan River has helped drive the retreat. By 2021, the river’s annual inflow was estimated at under 100 million cubic metres, compared with former flows of 1.2–1.3 billion.

Cassette tapes carried culture beyond official channels

Small, durable cassette tapes were easy to copy. Behind the Iron Curtain, they carried underground rock and punk. In Egypt, people used them to create and share culture and challenge regimes before public internet access.

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longfin damselfish mysid shrimp algae fertilization

Damselfish protect shrimp that fertilize their algae

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