The deepest parts of the ocean were thought to be too deep for life to exist, but scientists have found that, instead, they are the perfect environment for certain types of life forms.
A very large community of single-cell organisms was found in the Pacific at what is considered the deepest point of the sea floor on Earth.
The microbes that live there, are at a depth of about 11 km (7 miles) down in the Mariana Trench, the deepest scar of the ocean floor, situated about 200 miles south of the Island of Guam.
The trench is inhabited by as many as 10 times the amount of bacteria found in another deep trench of about 6 km depth, not too far from it. They seem to survive by scavenging the remains of sea life that drift to the bottom, algae and even other types of microbes that exist on the ocean floor.
The general consensus with scientist until now was that the deeper one went in the ocean, the less life there would be, because most of the food chain exists much above that level, and because it is a part of the ocean too deep for the food to drift down from the well oxygenated top layers of the sea where most marine life thrives.
But the bottom of the trench was apparently found to be very rich in organic matter, readily available for the bacteria to dispose of, even though the pressure at those depths is 1,100 times stronger than at sea level.
Not too long ago, the Mariana trench was visited by none other than famous director James Cameron, of Titanic fame, who made a courageous solo trip down the trench and recorded the marine life and scenery during his trip. Although Cameron described the trench as a desolate and seemingly barren place, where only extreme darkness reigns, and the temperatures are barely above freezing, what he could not see with the naked eye, was instead recorded by samples taken by a specially designed robot which made the trip unmanned to the sea floor fitted with ultra-thin sensors, and ultimately revealed the bacterial life.
However, these samples were not taken to the surface and were analyzed in situ, since the bacteria have adapted to the extreme habitat in which they live, and would have perished immediately if brought to the surface.
The new expedition also revealed that there are no large animal forms living at the bottom of the trench aside from the numerous microbes.
Source: France 24/ 3.17.13
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