Have you ever gone fishing in a lake or river? From time immemorial, fish has been close to Man either as food or pet.
Like human beings, fishes have backbones. There is a general misconception among common people that all animals that live in water are fish. That is manifest in addressing certain animas such as shellfish, starfish and cuttlefish as fish. However, that is incorrect because they are evidently different from true fish. The previously mentioned animals are invertebrates-animals without backbones.
There are mammals too. Whales and porpoises cannot be categorized as fish as they are mammals that have adapted to life in the sea. These animals cannot breathe underwater like fishes, as they have to come up to the surface to breathe.
Fishes, therefore, are aquatic animals with vertebra that live and breathe in the water. They have special anatomical features that help them in water such as gills, fins and scales. These animals possess basic vertebrate features, such as a brain, eyes, ears, blood, muscles and bones.
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