Dolphins are not fish.

Dolphins are a kind of mammal and an aquatic animal, they just live in the same environment as fishes, and they have a lot of similarities with fishes in terms of body structure and so on, so many people misunderstand that dolphins are fishes.

Dolphins and fish breathe differently, fish all use gills to breathe, while dolphins use their lungs to breathe, they can not be in the water for a long time, they need to swim to the surface of the water regularly to change air.

Dolphins reproduce differently from fish, which are mostly ovoviviparous, but there are some special fish species that reproduce oviparous. But dolphins reproduce in a viviparous manner, which is very different from fish. Dolphins are thermostats, and human habits are more similar, while most of the fish are thermotropic animals.

Life habits of dolphins

Dolphins swim fast, usually the fastest speed of 30-40km per hour, individual species of dolphins can be more than 55km / h, and can be maintained for a long time, is the long-distance swimming champion of the ocean.

Some dolphins are highly social species, living in large groups (sometimes consisting of more than 100,000 individuals) and exhibiting many interesting collective behaviors. Members of the group cooperate with each other in a variety of ways; one example is that dolphins in a cluster sometimes attack sharks, killing them by ramming them, and members also collaborate to rescue injured or sick individuals.

Dolphins feed primarily on fish and squid, with killer whales also preying on other cetaceans and finfoots. Like other toothed whales, dolphins rely on echolocation to hunt, and can even stun prey with high sound intensity.