? Dolphins are common animals living in the ocean, and there are many fish living with them. Some people think that dolphins belong to fish because they also live in the ocean, but in fact dolphins do not belong to fish, but to higher mammals. Although dolphins have structures similar to the fins of fish, they are not fins strictly speaking, but the result of "convergent evolution". That is to say, it is only because dolphins live in the ocean with many marine fish that they have evolved fin-like structures, such as dorsal fins and caudal fins, to better adapt to life in the ocean, which can play an important role in their swimming.
? As mentioned above, dolphins are not fish, so although they have fin-like structures on their bodies, they are not strictly fins. Dolphins live in the ocean for a long time and need similar structures to swim and hunt in order to survive in the sea. They also swim by these fin-like structures, which some biologists have named "flippers".
For example, the tail fin, when dolphins swim, they will rely on the swing of the tail to make their body move forward, and the tail plays a very important role in their swimming. In addition, dolphins need other flippers to help balance their bodies and change direction when swimming. Therefore, only the tail is not enough, all flippers need to work together, dolphins can swim more freely in the sea.
