Cancers are the orderlies of the environment in which they live. Most cancers, including hermit crabs, live in seas and rivers, but among the hermits there are not only deepwater species but also terrestrial species.
Sanitarians of crayfish are called because they are omnivorous. Young individuals live in tidal bands, where it is easier for them to find food. Among the algae, they collect all carrion, including the remains of animals. They feed like real gourmets: slowly bite off a small piece of claw and eat it.
One female may postpone up to fifteen thousand eggs within a year. She fastens the eggs to her abdomen and takes care of them, constantly piling up fresh, oxygenated water streams into the abdomen. About ten days later, larvae appear from the eggs, which will undergo four stages of growth.
The body of all young crayfish is covered with a dense shell. Rusty in it is impossible, so periodically young crayfish drop the shell and, increasing in size, again covered with a new shell. On the fourth molt, the hermit loses part of its shell in the abdominal region forever. His long abdomen is covered with the skin, bends under the breast and takes the shape similar to the shell.
As if ashamed of such a shame (at the same time fearing to become prey to other cancers), the hermit crab searches for a comfortable shell-eared shell and thrusts its soft abdomen into it, and leaves its head and pincers outside, but only until danger appears. In case of danger, it all squeezes into the shell and covers the entrance to it with a right, clad-covered claw, the benefit that the structure of the hermit cancer allows it to be conveniently located in shells of any configuration.
Other cancers continue to shed and grow. They live compactly. But hermit crabs are their exact opposite. They are loners. But meanwhile they love the society of other beings. For example, deep-water hermits permit on their shells to settle in an amazing and very poisonous fish - the sea anemones, so their shells seem shaggy. Cancer willingly runs in the shell with the actinia and feeds it with the remains of its food. Although poisonous actinia often causes the death of some predator, aimed at cancer, living in the shell. And then he eats it with cancer. Landless loners allow in their "houses" to settle in a multi-worm worm, creating such a unique hostel that gives both shelter and protection from predators. The worm does not allow annoying insects into the shell, and the cancer protects the worm from amphibian predators.
The digestive system of the hermit crab is very interesting. From the mouth through the pharynx and esophagus, its food enters the first section of the stomach, equipped with toothed chitinous grater. Pervertaya food comes to the second department, where it is filtered and enters the intestines, passes the digestive gland, where it is digested. The hermit crabs hermit with the gills attached to its limbs. The eyes have a very complex structure, since they consist of a set of separate optical lenses assembled in one eye, therefore the vision is mosaic.