The deep sea is where the ocean becomes deeper. It is also the point of transition from continental shelves to slopes.^[1] Despite the extreme pressure, organisms called deep sea fish can survive there. For example, the anglerfish can produce its own light source called an esca.

Some animals can thrive by feeding on marine snow.^[2] In 1960, a bathyscaphe called Trieste went down to the bottom of the Mariana Trench, which is the deepest point on Earth. There aren't any plants at all in these depths, so all fish in the deep are carnivores.

Some organisms can live in the deep sea, such as the gulper eel, lanternfish, anglerfish, and more. They have many adaptations that can help them survive in the harsh conditions.^[3]

Sunlight cannot reach the deep ocean, except parts of the mesopelagic zone.

The pressure is many high, so many people can't survive.

Exploration is very limited in the deep sea due to the extreme conditions.^[4]

1. ↑ "What is the deep ocean?". oceanexplorer.noaa.gov".
2. ↑ "Fish Food in the Deep Sea: Revisiting the Role of Large Food-Falls". PLOS ONE".
3. ↑ "Explaining bathymetric diversity patterns in marine benthic invertebrates and demersal fishes: physiological contributions to adaptation of life at depth". Biological Reviews".
4. ↑ "The deep-sea under global change. Current Biology".