Clownfish have become popular since the release of the animated movie "Finding Nemo." If you take a close look, you can always see clownfish and sea anemone living together. But why?

In fact, the clownfish is the only fish that can live with sea anemones and not be poisoned by their venom. Sea anemones are predatory marine animals whose tentacles can release fatal venom to kill fish for food. However, the clownfish is not afraid of the venom of sea anemones. Their skin is protected by a thick mucus layer which is three to four times thicker than that of other fish.

Clownfish and sea anemones not only can live together, they also can benefit from each other in a process called mutualism. Sea anemones can create a safe home that protect clownfish from being attacked by other fish. At the same time, clownfish will clean the anemones by eating their waste. Also, clownfish will act to attract other fish so that the anemones can kill them for food.

(All images via VCG)

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