- 行业: Biology
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Terrapsychology is a word coined by Craig Chalquist to describe deep, systematic, trans-empirical approaches to encountering the presence, soul, or "voice" of places and things: what the ancients knew as their resident genius loci or indwelling spirit. This perspective emerged from sustained ...
In experiments, scientists create artificial situations to test the hypotheses because they cannot make the necessary observations under normal conditions. Hypotheses are accepted for as long as they are supported by available evidence. This type of hypothesis is called as an alternative hypothesis.
Real marine biologists rarely have it as easy as our imaginary one, who was able to construct and then test his hypotheses about gills with just a few observations. Hypothesis testing reuires planned observations. The scientific process is a gradual one in which hypotheses are continually refined and modified, and new alternatives are produced, as more information becomes available.
Industry:Biology
Kelp communities are most fascinating of marine communities. Kelps are a group of large, brown seaweeds that live in cold waters. All kelps go through a large, spore producing sporophyte stage. The sporophyte is the organism we see.
In some kelps, sporophyte is an annual.In contrast, the giant kelps can live for several years. Kelp forests along the Pacific coast of North America are arranged in distinct depth zones.
Industry:Biology
Coral is a general term for several different groups of cnidarians, only some of which help build reefs. In reef-building, corals produce calcium carbonate skeletons. Billions of these tiny skeletons form a massive reef. Corals can produce their skeletons very slowly,not nearly fast enough to build a reef. The skeleton forms nearly all the bulk of the colony and can take many different shapes.
Industry:Biology
Most midwater animals have evolved an even more effective way to mask their silhouettes. Their bioluminescent photophores, found mostly on their undersides, produce light that breaks up the silhouette and helps the animal blend in with the background light filtering down from the surface. This adaptation, which functions in a similar manner to countershading, is called counterillumination.
The light produced by midwater animals is closely matched to the background light. Like the natural light at these depths, nearly all midwater bioluminescence is blue-green. Its interesting to know that many of these animals can control the brightness of the light they produce to match the brightness of the background.
Industry:Biology
Sea turtles belong to an ancient group of reptiles. Their bodies are enclosed by an armor-like shell, or carapace, that is fused to the backbone. Unlike land tortoises and turtles, sea turtles cannot retract their heads into the shell. Their legs, the large forelimbs, are modified into flippers for swimming.
Their shells may grow to 40 in in length. They feed mostly on seagrasses and seaweeds. Green turtles lack teeth, but they have strong biting jaws.Their diet consists largely of jellyfish. All the sea turtles must return to land to reproduce.
Industry:Biology
Sometimes symbionts benefit at the expense of the host, this is called as parasitism. The giant tapeworms that derive food and shelter by the guts of whales are considered parasites because they may weaken their whale hosts.
Marine parasites are very common. Few marine species escape having at least one kind of parasite.Some barnacles live on the skin of whales. They do not affect their host at all, most such barnacles obtain shelter, food, and some other benefit without affecting the whales one way or the other.
Industry:Biology
Many marine fishes, do not reside in any particular area. They are known to establish territories, home areas that that they defend against intruders. Thus, this phenomenon is called as terrotoriality.
This process is more common in crowded environments like kelps beds and coral reefs. The sense organs of these fishes like big eyes, taste buds, inner ears, and other specialized organs that pick up vibrations from the water.
Industry:Biology
Radiolarians are marine organisms that secrete elaborate and delicate shells made of glass( silica) and other materials. Typical shells are spherical with radiating spines, though the structure varies.
Thin, needle like pseudopodia capture food. Most radiolarians are microscopic, but some form sausage-shaped colonies that reach 9 ft in length, making them true giants among tiny sea creatures. Radiolarian shells are more resistant to dissolving under pressure than those of forams.
Industry:Biology
Most of the deep-sea floor lies at a depth of 16,500 ft. The deep-sea floor or abyssal plain, rises at a very gentle slope of less than 1 degree toward the mid-ocean ridge.Though relatively flat, it often has submarine channels, low abyssal hills, plateaus, rises, and other features. It is collectively termed as dee-sea basin.
This deep-sea basin is dotted with volcanic islands and submarine volcanoes called seamounts.
Industry:Biology
The volcanic island chains associated with the trenches follow the trenche's curvature and are called island arcs. When two oceanic plates collide, one of the plates dips beneath the other to form the trench. Again the trench is associated with earthquakes and volcanoes. The volcanoes may rise from the sea floor to create chains of volcanic islands.
The examples of island arcs include the Aleutian and Mariana islands. The Himalayas, for example, were formed when India collided with the rest of Asia. Two continental blocks push against each other with such tremendous force that the two continents become"welded" together.
Industry:Biology
