Why is it difficult for animals to live in the deep sea?
The deep sea, being an extreme environment, is completely different from the shallow sea. As the depth of the sea increases by 10 meters, the pressure rises by one atmospheric pressure. The water pressure in the deepest part of the ocean is 1,100 times greater than the air pressure on land. Under the high pressure that can be felt in the deep sea, any normal animal will have ruptured eardrums and collapsed lungs and suffocate immediately (Staughton, 2016).
The little sunlight in the deep sea, along with the very low temperatures, makes it difficult for plants to live there. As a result, the deep sea generally lacks food. Due to this environment, the deep sea has poor conditions for living creatures to live in (Staughton, 2016).
How does pressure impact animals in the ocean?
When the water pressure increases, the animal’s lungs contract, leaving only a small amount of air. The body of the animals sends much blood to the heart, and brain and the extra blood is adapted to expand the chest blood vessels to maintain balance with external pressure. The deeper the water, the slower the animal’s heartbeats (Venosa, 2015).
Water molecules have a tetrahedral shape, which is distorted when the water pressure is high. Changes in molecules that occur in a living body have harmful effects on animals, which cause them to eventually die (Fitzner, 2022).
The reason deep-sea fish can withstand underwater pressure
The fish’s skull is not fused, so it is not easy to break under pressure. They also have flexible bones that make it easier to withstand pressure. Liquid components cannot be compressed, unlike gases. Deep-sea fish do not breathe into their lungs. They fill the body with liquid and balance it with external pressure. Deep-sea fish have many substances called trimethylamine oxide (TMAO), which can resist extreme water pressure. This chemical prevents important molecules in a deep-sea fish’s body from being changed and compressed by the water pressure. Deep sea creatures have more of this material than other animals, so they can withstand extreme conditions in the deep sea (Staughton, 2016).
Future availability of chemicals in deep-sea animals
A substance called trimethylamine oxide is found in many deep-sea creatures. Researchers are studying ways to apply this material (Carpenter, 2022).
In 2009, a researcher injected TMAO into the eyes of glaucoma patients. Glaucoma is a disease that causes an abnormal increase in the amount of moisture in the eyeball, which increases intraocular pressure, stimulates the optic nerve, and impairs vision. In this case, if TMAO is properly injected into the eyeball, there is a possibility that high intraocular pressure can be endured (Carpenter, 2022).
A 2003 study found the possibility that TMAO could treat cystic fibrosis, a hereditary disease. Cystic fibrosis is caused by the abnormal secretion of mucus into organs such as the lungs and esophagus. Medical scientists are studying how to treat patients with the disease using TMAO (Carpenter, 2022).
Conclusion
The deep sea has no light, so the water temperature is low and the pressure is high in it, making it an unsuitable environment for living creatures. Therefore, deep-sea creatures have evolved uniquely to adapt to these poor conditions. Deep-sea creatures that do not need to see because the lack of light has deteriorated their eyes. The deep sea does not have much food because it lacks living things, so the mouths of deep-sea creatures have evolved into large ones to help them avoid missing their prey. The reason why creatures living in the deep sea look strange and have unusual habits is the result of adaptation to survive in the environment. Currently, there are many difficulties in studying deep-sea creatures at the scientific level, so most of them remain mysteries. A new possibility like TMAO will be found in the future by developing various research equipment.
References
Carpenter, K. (2022). Sea creatures’ fishy scent protects them from deep-sea high pressures. [online] Science News Explores. Available at: https://www.snexplores.org/article/fishy-scent-protects-sea-creatures-from-deep-sea-high-pressures [Accessed 10 November 2022].
Fitzner, Z. (2022). How do fish survive the intense pressure of deep water? [online] Earth.com. Available at: https://www.earth.com/news/how-do-fish-survive-the-intense-pressure-of-deep-water/ [Accessed 10 November 2022].
Staughton, J. (2016). Why Do Deep-Sea Fishes Not Get Crushed By Pressure on the Sea Floor? [online] Science ABC. Available at: https://www.scienceabc.com/nature/animals/deep-sea-fishes-not-get-crushed-pressure-sea-floor.html [Accessed 10 November 2022].
Venosa, A. (2015). Just How Much Pressure Can The Human Body Take? [online] Medical Daily. Available at: https://www.medicaldaily.com/breaking-point-how-much-water-pressure-can-human-body-take-347570 [Accessed 10 November 2022].
