Since ancient times, mankind has paid special attention to such unsightly creatures as the earthworm. And scientists, in the person of Charles Darwin, after decades, for many years studied their structure and significance in agriculture. And not without reason. After all, with the onset of spring heat, earthworms begin painstaking work and work without knowing it, for the benefit of people.
Features and habitat
Earthworm, he is ringed - a well-known resident in any household plot. And it would seem, an absolutely invisible, useless creature.
However, any person, at least somehow connected with the land, will be very glad to such residents of his garden. In the Russian Federation, there are no more than a hundred species of earthworm. But around the world there are fifteen hundred species.
It belongs to the family of annelid worms, low bristle class. His entire long body consists of many rings. There may be seventy, or maybe all three hundred. Since it grows in length more than twenty-five centimeters.
But there are also the smallest, two or three centimeter. In Australian earthworms, reach two and a half meters in size. Its color in the literal sense of the word gray-brown is raspberry.
Also, on each ring, or it is also called a segment, there are bristles. In our ordinary garden worms, as a rule, eight setae grow. They are classified as low bristle.
However, there are tropical, multi-bristle species of worms in which villi grow in dozens. The bristles help the worms crawl along absolutely all soil tubercles or burrow into burrows.
You can detect them by taking the worm in your hands and swiping your finger from back to front. But since it is difficult for an inexperienced person to determine where his butt is, you can simply gently move your hand along the body and back. You can immediately feel it. In one direction, the worm will be absolutely smooth, and, having drawn in the opposite direction, will be rough.
Anyone who has ever taken a worm in their hands knows that it is all covered with not very pleasant mucus, which is vital for him. Firstly, the mucus helps the invertebrate to move freely in the ground. Secondly, since the worm has no lungs, it breathes through the skin. And thanks to the moisture located on the mucus, the body is saturated with oxygen.
Itself earthworm body consists of two groups of muscle tissue. They are longitudinal and transverse. The transverse muscles are located under the protective upper layer of the skin of the worm.
With their help, the worm becomes as long as possible. And stronger muscles are longitudinal. They contract, contract the body. So, now lengthening, then shortening, the animal moves.
Earthworm refers to celiac animals. Therefore, he has a full-fledged closed circulatory system. Since their vital activity is active.
Muscles contract many times more often than in primary-celled worms. To do this, they need blood to provide the worm with all the nutrients and oxygen.
IN earthworm structure there is a pair of blood vessels, one of them is called the dorsal, the second abdominal. Ring vessels connect them together. Blood flows through them from back to front, and vice versa.
In each ring, or as it is also called a segment, there is a pair of tubes. The funnels at their ends open and excrement is removed through the bottom earthworm. This is the principle of the excretory system.
As for the nervous system, it is nodal. Its components are the abdominal nerve chain and the periopharyngeal nerve ring. These endings consist of fibers, and those, in turn, respond to the urges of the contracted muscles of the worm. Thanks to them, the worm can eat, purposefully move, multiply, develop.
In the building earthworm organs there are no those responsible for the sense of smell, touch, sight, and sensation. But there are certain cells, they are located along the entire body of the invertebrate. With their help, the worm navigates in the dark and impassable land.
Character and lifestyle
Charles Darwin also suggested the existence of intelligence in earthworms. Watching them, he noticed that pulling a dry sheet to his home, he turned it exactly the narrow side. Which facilitates the leaf through the dense, earthen hole. But spruce needles, on the contrary, take as a basis so that they do not bifurcate.
All day all rain life the worm painted by minute. He continually climbs the earth, makes moves, swallowing it. Digging a worm in two ways. He or, as already mentioned, swallows the earth, gradually moving forward.
In case the earth is too hard. And after leaving their biological waste. Or, shoves it with its sophisticated end, in different directions, and makes moves for itself. The passages are obliquely vertical.
Tech rain worm, fishing in the soil, pulls into his holes, for warming, various leaves, veins from leaves, thin pieces of paper and even shreds of wool. Its burrows are up to one meter deep. And the worms are larger in size, and all ten meters. The worm works mainly at night.
BUT why earthworms in huge quantities creep out to the surface. This means that he has nothing to breathe. This usually happens after heavy rains. The earth is clogged with moisture, and it does not have oxygen at all. Upon the arrival of cold weather earthworm goes deep into the soil.
The worm’s nutrition is fairly typical. Swallowing large quantities of land with food. For food, they are suitable for sluggish and slightly rotted leaves, mushrooms. But it should not have an unpleasant smell, otherwise the worm will not eat it.
It turns out that earthworms even build themselves whole storage rooms, and put food there by winter. They eat it only in case of critical need. For example, in winter, when the soil is completely frozen, and there can be no talk of any ground food.
Having sucked food along with a lump of earth, through the throat, with muscle movements, then expanding his body, then narrowing, he pushes it to the back of the esophagus in the goiter. After, it penetrates the stomach. It is sent from the stomach to be overdone in the intestine, thanks to enzymes, it comes out to the surface with useful biomasses.
Making moves, and at the same time snacking, rain the worm necessary crawl out periodically to the surface to throw off the ground. At the same time, he adheres to the hole with his tail edge, as if holding onto it.
And after, there are always earthen slides. The soil processed by the worm is sticky. It dries up the note, and becomes small, with a match head with balls.
These balls are saturated with vitamins, enzymes, organic substances, which, as a result, kill all bacteria in the ground, prevent rotting, which is very important for plant roots. And they act on the composition of the earth as an antiseptic, disinfecting it.
Reproduction and longevity
Earthworms can be heterosexual, and hermaphrodites. All earthworms on the front third of their body have thickenings. They contain the ovary and testis. Hermaphrodites let in a seed into each other. Already ripened testicles, within ten pieces, are inseminated. And creep away in different directions.
When a female individual is already ready for reproduction, she approaches her partner and copulates. On it, something like a cocoon is formed, consisting of several dozen thickened segments.
It is divided by a kind of belt. All the nutrients necessary for brood enter this cocoon. After fertilization, the worm removes this burden from itself, it simply slides off the animal.
The edges on the cocoon, on both sides are quickly pulled together so that future offspring do not dry out before they are born. Then, within four weeks, small worms mature and bear.
Having been born, they creep where to where. And from the first days of their lives they begin active work on the processing of land. And already at the age of three months, grown up children reach the size of adults.
Another fact about earthworms is the ability to regenerate. If someone, or something, divides him into two halves. Over time, each of the halves will become a full-fledged individual. This is one of the methods of reproduction, but not by sexual means.
And an unpleasant fact, worms are a "capsule" for storing parasites in it. And if a worm is eaten by a chicken or a pig, there is a high probability of helminth infection of an animal or bird. The life of the worm lasts more than five to six years.
The role of the earthworm in agriculture is very important. Firstly, they saturate the soil with oxygen, so necessary for everything growing on it. With their moves, they help the roots to fully develop.
Moisture is evenly distributed, and the soil is well ventilated, loosens. Thanks to the constant movement of the earth, with the help of worms, stones are extracted from it.
Also, with their recycled adhesive residues, they glue the soil, preventing it from eroding. Well, and of course they fertilize the earth when they drag in leaves, insect larvae. It all rots and serves as excellent, natural bio-supplements.