Actually thats a question of the evolution. A fish that lives near by the sea can say "aw, I don't want to stay here, I go to the deep sea". Just because of factors like the sunlight or something like that they coulnd't live there. They adapt during many generation, and adapt slowly to the new circumstances. That's the same with a fish that lives in the deep sea. If you bring him up, and my not survive, because he can't stand for example the pressure. It's actually a question of time and developement.
Salt water crabs Salt water lobster Sea otter Sea turtles
Deep sea fish evolved without scales as a way to adapt to the extreme pressure and darkness of the deep sea environment. Scales are not necessary for protection from predators or to regulate buoyancy in the deep sea. Instead, these fish may have developed other adaptations such as a gelatinous skin or spines for camouflage and defense.
Deep water
Deep sea
move in, get friendly with the neighbours. the norm...
The phrase "deep blue sea" means any deep water - if you have ever seen really deep ocean or lake water, you know that it is a really deep blue, almost black, color.
deep inside the sea water
The deep sea has high water pressure due to the weight of the water above it. As you descend deeper, the pressure increases significantly. Conversely, the air pressure at deep sea depths is relatively constant and does not change as dramatically as water pressure.
Shut up ba students
Light doesn't reach that deep. It is absorbed and blocked by the water.
They live in shallow sea water
You can do water sports in the Agean. It is deep and warm.