Tuna is a kind of fish. In terms of category, tuna belongs to bony fish. In addition, the classification of fish can also start from their distribution waters, according to which they can be divided into marine fish and freshwater fish. These are two completely different types of fish, and the differences in appearance and habits are quite large. In this respect, tuna belongs to marine fish, because they are mainly distributed in the ocean, and relatively deep in the ocean.
Specifically, the distribution range of tuna is relatively wide, and it is distributed in many sea areas of the world. For example, the Pacific Ocean, the Atlantic Ocean and the Indian Ocean are all distributed in it. Especially in latitudes close to the equator, that is, where the water temperature is more suitable, tuna are widely distributed. The Arctic Ocean is basically not distributed, because their latitude is too high. Specifically, the distribution of different species of tuna is also different, but generally speaking, they are in the sea area.
As mentioned above, tuna belongs to marine fish, so in the long process, their body structure has adapted to the marine environment, and their living environment can not be changed too much. If tuna are placed in fresh water, they will not be able to adapt and it will not be easy to feed them. This is because the difference between sea water and fresh water is very large, and the salinity is an important difference. Tuna have physiological mechanisms that can adapt to seawater, such as high salt concentration in their cells, but this mechanism is not suitable for freshwater, if put into freshwater, water will enter the cells of tuna because of the concentration difference, they may die because of excessive water absorption.
