What is a fish classified as?
Fish are aquatic vertebrate animals that have gills but lack limbs with digits, like fingers or toes. Recall that vertebrates are animals with internal backbones. Most fish are streamlined in their general body form. The word fish is the same whether it is singular or plural—you can talk about one fish or ten fish.
Is dolphin a mammal?
Dolphins are mammals, not fish
Like every mammal, dolphins are warm blooded. Unlike fish, who breathe through gills, dolphins breathe air using lungs. Dolphins must make frequent trips to the surface of the water to catch a breath.
Are sharks mammals or fish?
Are sharks fish? Sharks are fish. They live in water, and use their gills to filter oxygen from the water. Sharks are a special type of fish known because their body is made out of cartilage instead of bones like other fish.