Clownfish

The clownfish is a small, bright orange fish with bold white stripes edged in black. It lives on warm coral reefs, and it almost always stays close to one special home: a sea anemone.

A sea anemone looks like a soft, waving flower, but its tentacles can sting. Most fish keep away, yet the clownfish snuggles right in. A slippery coat over its body keeps it from being stung, so the anemone becomes a safe hiding spot from bigger fish.

The two animals are a team. The anemone gives the clownfish shelter, and the clownfish keeps the anemone tidy and chases away little pests that might nibble it. Helping each other like this is called living together, and both are better off for it.

Clownfish have a surprising social system. Young fish are immature, and each group develops a size-based order. The largest fish is the breeding female and the next largest is the breeding male. If the female disappears, that male can change sex and become the group's new female.

Clownfish eat tiny bits of food that drift by, like plankton, small shrimp, and bits of algae. There are plenty of them across the warm oceans today, but they need healthy coral reefs to thrive, so looking after reefs helps keep clownfish happy and safe.