Adaptations of the deep-sea creatures


The Enviroment

The deep sea is a very harsh environment. The light from the sun does not reach all the way to the deep sea, making it pitch black. The deep-sea is very cold, has low amounts of oxygen, and the pressure is very high. Food in the Deep Sea is very scarce. Due to these conditions species that live here found many ways to adapt to this environment

How do organisms in the deep sea find their way through the ocean without any sunlight?


Some Species here commonly use bioluminescence light. Bioluminescence is a chemical reaction in an animal’s body that creates light without heat. Most bioluminescence light is blue or blue-green because the color blue travels farthest in the water. As a result, many animals in the deep sea cannot see colors like red light, (the color of sunlight) for sunlight is inexistent in their part of the ocean. But a few creatures like the Dragonfish have evolved to produce red bioluminescence light. This gives these organisms to snipe their prey with this light that is invisible to their prey. Bioluminescence light is much weaker than sunlight so the animals here have special sensory adaptations. Many deep-sea fish have very large eyes to capture more of the little light that exists. Other animals are blind and rely on their other specialized senses like smell, taste, and touch. In this way, these organisms adapted to the pitch-black environment of the deep sea.

How do these organisms adapt to the extremely high pressure of the deep sea?


The pressure in the deep sea increases one atm every 10m of depth. High pressure can cause air pockets in a fish to be crushed. High pressure distorts biomolecules like membranes and proteins, that are needed for every living thing. Life in the deep sea has membranes and proteins that are pressure-resistant structures. This means their biomolecules don’t work well in shallow waters with low pressure. Some organisms use “piezolytes”. Piexolytes are small organic molecules that prevent pressure from distorting large biomolecules.

How do organisms survive the intensely cold water temperatures of the deep sea?


The deep-sea temperature ranges from -1 to about +4°C. Life in the deep sea adapts to these extremely cold temperatures by having flexible proteins and unsaturated membranes that do not stiffen up in the cold. Membranes are made out of fat and are flexible to work well. For example, Butter, a saturated fat becomes hard in cold temperatures such as the refrigerator. On the other hand Olive oil, unsaturated fat is semi-solid, making a good flexible membrane. The pressure makes these fats to become more solid, enabling the fish in the deep sea to have a fish-like form. But once the creature is in a low pressured, higher temperature area the creature form will fall apart.


Food is significantly scarce in the deep sea. Scavengers on the ocean floor eat the decaying remains of microbes, algae, plants, and animals from above. The corpses of larger animals such as whales that sink to the bottom provide a feast to deep-sea animals such as jawless fish.