it depends what it is. they could survive on other living substances, they could also have different kinds of habitats for different kinds of animals...
how do deep sea bacteria survive
elephants
http://www.allthesea.com/Deep-Sea-Fish.html go to this website it has lots of info on deep sea fish
It does not. It does not have predators in the deep sea.
Because if there a sea animal and they are born in the sea then they adapted to swimm
A bivalve. A clam (A brachiopod)
they use very strong, thick materials or equilize the pressure on the inside to be the same as the outside
These organisms do not need oxygen. They are called anaerobes.
Sharp eyes, suckers, and big lungs
Food, water, an acceptable habitat, and time.
You need special equipment to survive the extreme and dangerous conditions.
Because that is the only known ecosystem that is not dependent on the sun to sustain life.