What does puffer fish mean?

Fish, round head, small mouth, dark brown back, white abdomen and often yellow fins. The meat is delicious, and the ovary, blood and liver are highly toxic. Living in the sea, some also enter rivers. Also known as swallowing (tún).

Please click on the input picture to describe that puffer fish is not a single thing.

Freshwater dolphins in a broad sense refer to all whales and dolphins living in fresh water. For example, the "2006 Yangtze River Freshwater Dolphin Survey" initiated by scholars from many countries in China in 2006 is about these two unrelated species. Freshwater dolphins in a narrow sense refer to several cetaceans with long beaks, round foreheads and small eyes, which are summarized by morphological taxonomy.

The baiji belongs to this category, while the finless porpoise does not. In addition, the puffer fish, which mainly lives in the sea, also belongs to this category, because it has a typical appearance of freshwater dolphins.

Some scholars have merged all the freshwater dolphins in a narrow sense into the long-finned dolphin family or the long-finned dolphin family, which are called freshwater dolphins and freshwater dolphins. In fact, the similarity in appearance and habits of these freshwater dolphins is the result of convergence and evolution caused by similar habitats, and does not mean that they are closely related.