Deep sea creature
The term deep sea creature refers to organisms that live below the photic zone of the ocean. These creatures must survive in extremely harsh conditions, such as hundreds of bars of pressure, small amounts of oxygen, very little food, no sunlight, and constant, extreme cold. Most creatures have to depend on food floating down from above.
These creatures live in very demanding environments, such as the abyssal or hadal zones, which, being thousands of meters below the surface, are almost completely devoid of light. The water is between 3 and 10 degrees Celsius and has low oxygen levels. Due to the depth, the pressure is between 20 and 1,000 bars. Creatures that live hundreds or even thousands of meters deep in the ocean have adapted to the high pressure, lack of light, and other factors.
These animals have evolved to survive the extreme pressure of the sub-photic zones. The pressure increases by about one bar every ten meters. To cope with the pressure, many fish are rather small, not exceeding their flesh and more minimal their . These have also eliminated all excess cavities that would collapse under the pressure, such as []. "">[://marinebio.org/Oceans/Deep/ The Deep Sea at MarineBio.org - Ocean biology, Marine life, Sea creatures, Marine conservation]</ref>
Bioluminescence is the ability of an organism to create light through chemical reactions. Creatures use bioluminescence in many ways: to light their way, attract prey, or seduce a mate. Many underwater animals are bioluminescent—from the viper fish to the various species of flashlight fish, named for their light. Some creatures, such as the angler fish, have a concentration of photophores in a small limb that protrudes from their bodies, which they use as a lure to catch curious fish. Bioluminescence can also confuse enemies. The chemical process of bioluminescence requires at least two chemicals: the light producing chemical called luciferin and the reaction causing chemical called luciferase. The luciferase catalyzes the oxidation of the luciferin causing light and resulting in an inactive oxyluciferin. Fresh luciferin must be brought in through the diet or through internal synthesis.
Since, at such deep levels, there is little to no sunlight, photosynthesis is not a possible means of energy production, leaving some creatures with the quandary of how to produce food for themselves. For the giant tube worm, this answer comes in the form of bacteria. These bacteria are capable of chemosynthesis and live inside the giant tube worm, which lives on hydrothermal vents. These vents spew forth very large amounts of chemicals, which these bacteria can transform into energy. These bacteria can also grow free of a host and create mats of bacteria on the sea floor around hydrothermal vents, where they serve as food for other creatures. Bacteria are a key energy source in the food chain. This source of energy creates large populations in areas around hydrothermal vents, which provides scientists with an easy stop for research. Organisms can also use chemosynthesis to attract prey or to attract a mate.
Deep sea research
Humans have explored less than 3% of the ocean floor, and dozens of new species of deep sea creatures are discovered with every dive. The submarine DSV Alvin—owned by the US Navy and operated by the Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Massachusetts—exemplifies the type of craft used to explore deep water. This 16 ton submarine can withstand extreme pressure and is easily manoeuvrable despite its weight and size.
The extreme difference in pressure between the sea floor and the surface makes the creature's survival on the surface near impossible; this makes in-depth research difficult because most useful information can only be found while the creatures are alive. Recent developments have allowed scientists to look at these creatures more closely, and for a longer time. A marine biologist, Jeffery Drazen, has explored a solution, a pressurized fish trap. This captures a deep-water creature, and adjusts its internal pressure slowly to surface level as the creature is brought to the surface, in the hope that the creature can adjust.
Another scientific team, from the Universite Pierre et Marie Curie, has developed a capture device known as the PERISCOP, which maintains water pressure as it surfaces, thus keeping the samples in a pressurized environment during the ascent. This permits close study on the surface without any pressure disturbances affecting the sample.
In popular culture
|Wikimedia Commons has media related to Deep sea fauna.|
- Monterey Bay Aquarium: Online Field Guide
- BL Web: Chemistry
- New Trap May Take Deep-Sea Fish Safely Out of the Dark
- Lever, Anna-Marie (31 July 2008). "Live fish caught at record depth". BBC News. Retrieved 18 February 2011.
|Wikisource has the text of the 1920 Encyclopedia Americana article Deep-Sea Life.|
- Deep Ocean Diversity Slideshow - Smithsonian Ocean Portal
- Sea and Sky: Monsters of the Deep Sea - Details about specific creatures
- Monterey Bay Aquarium: Online Field Guide - Details about specific creatures
- The Bioluminescence Web Page - Good resource on bioluminescence
- NeMO Explorer - Good resource on chemosynthesis
- Undersea Wonders - slideshow by Life magazine
- Deep Sea Creatures - Articles, facts and images of deep sea animals