โ† All Nature and Animals topics
Nature and Animals ยท Topic 18 of 65

Fish

Fish breathe underwater using gills and swim with fins. Most fish lay eggs, and many have scales.

๐Ÿ’ก Fun fact

The whale shark is the biggest fish in the world.

All about Fish

Fish are cold-blooded, water-dwelling animals with fins, gills and usually scales. They breathe underwater by pulling water over their gills, which take oxygen from it. Fish live in oceans, rivers, lakes and even deep caves.

There are more than 30,000 known species of fish, making them the largest group of vertebrates. Most fish lay eggs, and a few give birth to live young. Their fins help them steer, balance and swim.

๐ŸŽฎ Try it yourself!

Loadingโ€ฆ

Real-life uses of Fish

  • Providing food for billions of people
  • Helping people learn about water ecosystems
  • Being kept as pets in aquariums

Frequently asked questions about Fish

Can fish breathe out of water?

Most cannot, but a few species, such as some lungfish, can breathe air for short periods.

Do fish sleep?

Yes, in a way. Many fish rest with reduced activity, and some float or hide while their brains rest.

What is the biggest fish?

The whale shark, which can grow longer than a bus, is the largest fish alive today.