Do ? Dolphins are animals that live in the ocean. Although they live in water, they are not fish, but higher mammals. Fins are one of the structures that make up fish, which can move freely in the water. Although dolphins are not fish, they have fin-like structures on their bodies, but they are not fins in the strict sense. Some biologists have named them "flippers" to show that they are different from fish fins.
Dolphins have developed this kind of structure in the long process of evolution because they live in the water and need to adapt to the life in the water, so they have developed such a similar structure. When dolphins are swimming, their tail fins play a very important role, and the swing of the tail fins can drive them forward in the water. In addition, other flippers can also play an important role when dolphins maintain their balance in the water, and these structures are indispensable to dolphins.
. As mentioned above, although dolphins have fins, they are not fins in the strict sense, but flippers, because they are not fish themselves. Specifically, dolphins have caudal, pectoral, and dorsal fins. The caudal fin is actually their tail, which plays the most important role when they swim in the water. There are two pectoral fins, which are distributed on both sides of their bodies. The dorsal fin is their back, which is similar to the dorsal fin of fish, and plays an important role in keeping dolphins balanced. However, there are very few dolphins with pelvic fins, but such dolphins are very few.
