Deep sea and trenches
The ocean is deep, very deep in some places. The deepest recorded measure to date is the Mariana Trench, near the Philippines, in the Pacific at 10,924 m (35,838 ft). Water pressure at these depths is extreme and there is no light from above, but some life still exists here. Small flounder Soleidae fish and shrimp were seen by the american crew of the Bathyscaphe Trieste when it dived to the bottom in 1960.
Other notable deeps include Monterey Canyon, in the eastern Pacific, the Tonga Trench in the south west at 32,000 feet, the Philippine trench, the Puerto Rico Trench at 8,605 m (28,232 ft), the Romanche Trench at -7,760 m (24,450 ft), Fram Basin in the Arctic at -4,665 m, the Java Trench at 7,450 m (24,442 ft), and the South Sandwich Trench at -7,235 m.
In general the deep sea is considered to start at the photic zone, the point where sunlight looses its power of transference through the water.
Many life forms that live at these depths have the ability to create their own light.
Much life centers around seamounts that rise from the deeps. Fish and other sea life use these as congregating areas, for spawning, and feeding.
Hydrothermal vents in the ocean floor act as oasis's for life. As well as their opposites, cold seeps. These places support unique biomes and many new microbes have been discovered at these places.
How oceanic factors affect distribution of various organisms
An active research topic in marine biology, is discovering and mapping the life cycless of various species and where they spend their time. How the ocean currents affect them. And the effect of the multitudes of other oceanic factors on their growth and well being. This has only recently become technically feasible with the support of GPS and newer underwater visual devices.
Most ocean life and fish breed in specific places, nest or not in others, spend their time as juveniles in still others, and in maturity in yet others. Scientists were at a loss for quite a while as to the location of many species during different parts of their life cycles. In fact where sea turtles travel is still largely unknown. Tracking devices just don't work for some life forms, and the rigors of the ocean are not friendly to technology. But these factors are being overcome in many instances.
History of marine biology
In recent times, marine biologists are trying to complete the mapping of underwater species with the help of modern techniques, which could help in exploring the deepest oceanic depressions in which it is supposed that new species could be found, eventually of potential great interest also for the theories on evolution.
Institutions, well-known journals
Many universities teach courses in marine biology.
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