* Appearance: Dolphins are streamlined, live in water, and have fins, which are features commonly associated with fish.
* Lifestyle: Dolphins spend their entire lives in water, swim, and eat fish, further reinforcing the impression that they are fish.
* Lack of knowledge about marine mammals: Before the development of modern science and understanding of marine biology, people had limited knowledge about the diverse range of creatures that inhabit the oceans.
However, dolphins are actually mammals:
* They breathe air: Unlike fish, dolphins need to come to the surface to breathe air using lungs.
* They give birth to live young: Dolphins are viviparous, meaning they give birth to live young, unlike fish that lay eggs.
* They nurse their young: Dolphins produce milk to feed their offspring, a characteristic of all mammals.
* They are warm-blooded: Unlike fish, dolphins maintain a constant body temperature independent of the surrounding environment.
The scientific classification of animals has made it clear that dolphins are mammals, not fish. However, the common misconception persists because of the familiar appearance and aquatic lifestyle of dolphins.