The denizens of the deep
What is life in the dark, deprived of light the depths of the ocean? The deeper one penetrates into the sea the daylight is, the faster it weakens. A traveler in the depths of the ocean V. Beebe writes that the water in the upper 50 m green color, at the depth of 60 m is greenish-blue or blue-green, 180 m in her clear blue color, at 300 m is a weak blackish-blue. Even at a depth of 580 m Bib caught the last traces of light. Various devices with photographic plates, and more precisely with the help of photomultiplier cameras detected that the light penetrates into the ocean to a depth of 1500 m. Deeper no devices it not get it. But animals and deeper 1500 m. They exist here in complete darkness, in which only here and there the glimmer of ghostly lights cold “living light”. Even on the biggest depth of about 11 thousand m — you can find animals. At this depth, they feel a tremendous pressure.
Life on the sea bottom at a depth of 3-5 m In the center — luminous brittle star hitching a ride, a spider crab and cancer munidopsis. For them. — animals leading a sedentary lifestyle, sea feathers. Top left — red crustacean shrimp.
The oceanic environment is called the realm of monotony. This is particularly true with respect to the depths of the ocean. Here in the water there are almost no oscillations of temperature and salinity. In the depths of the ocean and on its bottom life compared to being coastal in thousands and tens of thousands of times poorer. At the coast the number of benthic animals are often expressed by hundreds of grams or even a few kilograms per square metre of seabed. And in the depths of the ocean is equal to the number of sometimes only a few milligrams on the same area of bottom. The density of plankton in the coastal waters reaches hundreds, sometimes thousands of milligrams per 1 m 3. but in the depths it is limited to milligrams or even fractions of a milligram. This is primarily due to the abundance of food, at the coast and the lack of it in the depths of the ocean.
Deep-sea glowing fish and other glowing animals.
The population of the surface areas of the ocean has about 170 thousand species of various animals, mainly protozoa, sponges, coelenterates, worms, arthropods, echinoderms, fish and mammals. The deeper, the smaller species, and at the great depths of the ocean inhabited by only a few hundreds or even tens of species. There prevail rhizopods foraminifera, sponges, intestinal cavity, worms, crustaceans and echinoderms. Deep-sea fish live on smaller depths.
In our time the study of the life of the deep sea has made significant progress. Much of the credit for this belongs to the Soviet scientific expeditions, conducting research in the Pacific, Atlantic and Indian oceans.
Deep-sea fauna has been formed gradually, starting from the earliest geological epochs. She continues to create and now. Therefore, its composition is very ancient forms, and still very young. A remarkable discovery has been made of the Danish deep-sea expedition that sailed on the vessel “Galatea”. In the Pacific ocean West of the Mexican coast from a depth of 3.5 km was caught amazing clam neopilina. It is the representative of a special class, which was widespread in the shallow seas hundreds of millions of years ago in ancient geological epochs. Obviously, for long geological periods of life conditions in the ocean depths almost have not changed, which, of course, could not be in the surface layers of the ocean.
In the depths of the far Eastern seas and in the deep basins of the Pacific lives a group of marine invertebrates, similar to vertebrates, pogonophora. This group is very ancient, and learned about it only when they began to study deep-sea fauna. Now Soviet marine expeditions collected dozens of species of these peculiar animals. Obviously, pogonophora in ancient geological epochs inhabited the shallow sea, then they became extinct and only survived in the depths of the ocean.
Deep-water fauna was formed, obviously, in the area of cold and temperate seas, where animals, plunging into the deep, have not seen significant temperature changes. Part of the deep-water fauna could occur in the tropical zone of the ocean.
Very interesting and varied adaptations of deep-sea animals to exist in the ocean depths. There are a lot of predatory fish — their appearance clearly tells about the way of life. They have a huge mouth with long sharp recurved teeth; it seems that all the animal consists of a single mouth. The trunk is usually disproportionately thin, sometimes short.
Many of these predators the whole mouth glows from the inside, and the poor victim it’s tempting to look back, and a predator that is waiting for and try look! The fish-anglerfish to attract victims is another clever device: just before the mouth on the long tentacle-rod swinging and flashes different lights small flashlight — just like a traffic light on the street, and even color are the same. The victim, attracted by the light, swim to the mouth of a predator, and curiosity is paid for life. And where only the predators of the deep are not placed glowing bodies: and under the eyes, as the headlights of cars, and on the sides of the body, and even in several rows, so that from a distance the fish look like a passenger ship at night.
In addition to the glowing lures of deep-sea animals have very long thin antennae. Sometimes long tendril stretched they end of the tail. This is all very sensitive organs of touch, is able to detect the slightest fluctuation of water. And some crustaceans living in the depths, antennae and legs are extremely long and thin. All these devices need to locate prey — because it is so little in the depths of the ocean.
Next kind of signs and possess those deep-sea animals that live on the seabed or in the ground, such as sea cucumbers. Many of them are lacking color. They look grey, colorless. They all grunted. Filling your gut large portions of the soil, use organic matter and bacteria. The ocean storm has just begun. A vast field of activity open in this area for you, the future conquerors of the ocean depths.