A scientist has been studying spiders for more than 2 years. He said, "This is a very interesting thing, because it doesn't seem to make any sense. You can't see any advantages of a symmetrical web, but it is an evolution of spiders." He also said that this can't be an accident in evolution, which just gives these spiders the ability to measure. There must be a reason for this evolution, but we don't know it yet.
Among more than 37, spider species, all spiders can spin silk, but only half of them can weave webs with silk, and the rest can only wrap food or eggs with silk, or weave a small temporary shelter, or weave a safety belt when jumping like Spider-Man.
Spider silk comes from the spinner and is usually located at the back of the abdomen. Linda Ryle, an assistant professor at the College of Entomology at Cornell University in new york, said: "Silk exists as a liquid in the abdomen, but it turns into a solid silk when it comes out. Researchers have been studying how this happens. Spider silk is much harder and more flexible than steel with the same width, and it can stretch to 2 times its length. "
Every spider has its own type of web, which is both natural and easy for experts to recognize. A scientist said, "Give me any kind of web on the earth and I can tell the kind of spider that weaves this web, just like an artist can tell the works of Michelangelo and Van Gogh at a glance."
However, just as each painting is unique, each web is built by each spider according to the specific space. The biology professor at Vassar College in new york said, "Spiders will modify the web design according to the wind and the surrounding vegetation."
The scientist said, "The best known symmetrical web is woven by those spherical spiders. There are about 5, kinds of spiders that weave spherical webs." The ball net consists of a radial circle, and the middle part protrudes into a spiral shape to trap food. He said: "spiders can't catch more food by creating symmetrical webs than asymmetric webs, so why do they bother to weave such regular webs?"
at present, there is no reason to explain the symmetry of cobwebs. However, Ryle speculated that the symmetry of radial cobwebs may have biodynamic reasons. To be practical, a spider web must be woven so that insects can't break free or bounce out. Ruier said: "When insects collide into the net, the cobweb must bear the collision force, and the advantage of the symmetrical net may be that it can distribute this force evenly throughout the net to reduce the stress at a certain place, so as to avoid the net from being torn as much as possible."
the main feature of a web-forming spider is its web-forming behavior. Spiders secrete mucus through the protrusions at the tip of their silk sacs, which can condense into very thin silk when exposed to air. The web made of silk is highly sticky, which is the main predation means of spiders. But why don't spiders stick to themselves during the web-making process?
It turns out that the spider's leg and heel secrete a special oily liquid, and it is the lubrication of this liquid that makes the spider come and go freely. There are several spinners at the end of the spider's abdomen, which can spin different kinds of silk. Some spider silk is not sticky (dry silk), while others are sticky (sticky silk). When a spider weaves a web, it first weaves a bracket and spokes radiating outward from the center with non-sticky spider silk, and then weaves coils of spiral screws with sticky spider silk. As long as the spider doesn't touch the screw, it won't get stuck. In other words, spiders move on non-sticky spider silk, so they will not be stuck.
Living habits
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Spiders feed on insects, other spiders and polypods. Jumping spiders have good eyesight and can dive close to the prey within 5 or 1 meters and pounce on it. Crab spiders wait for their prey on flowers close to their body color. The ground spider that burrows in the soil builds a cave lined with silk, and the hole has a living cover that opens at night to prey on insects passing through the hole. Funnel spiders weave a flat net, which causes vibration when insects are caught; Spiders themselves live in silk tubes, with narrow ends leading into plants or crevices. Most circular spiders weave the largest net with the least silk, which is like an air filter, trapping insects that don't see filaments and have weak flying ability. Although the net is complex, it can usually be woven within one hour, and it is usually finished before dawn. If the net is destroyed during predation, weave a new net. Why the spider itself is not stuck by the web, and how to cut off the extremely elastic silk when weaving the web, these problems have not yet been fully understood. When weaving a round net, the spider gives off a trace, and the soup floats with the wind. If the free end of the silk fails to stick to something, the spider pulls the silk back and eats it. If the silk is firmly stuck to something (such as a branch), the spider will cross the silk bridge and reinforce it with silk. The spider holds a thread in the middle of the bridge, falls on a thread and hangs down, and sticks it to the ground or another branch. The spider returned to the center, and Radogan radiated radiation from the center of the net. Then, the spider crawled back to the center of the net and pulled temporary spiral wires from the inside to the outside, with a large spacing between the spiral wires. Then the spider climbs to the outermost periphery, and places a sticky and compact insect-catching spiral wire from the outside to the center of the net. While knotting, eat the previously knotted dry spiral silk without stickiness. After the net was completed, some spiders pulled a silk (signal silk) from the center of the net and climbed into the leaves in the corner of the net to hide. If an insect throws a net, it can hear the news and feed through the vibration of the signal wire. Some spiders stay head-down in the center of the net, waiting for their prey. When there is prey, they first wrap it with silk, then bite it and take it back to the center of the net or a hidden place to eat or store it. Butterfly moths are large and easy to escape, so they are first bitten and then tied with silk. Some spiders * * * use webs, such as the social funnel spider (Agelena conso ciata) in Gabon to build a big web, and hundreds of spiders * * * prey together. Spiders may play an important role in controlling the population of some insects. The neurotoxicity of several poisonous spiders is toxic to people. The process of web-weaving has aroused scientific interest and has been used to study drugs that affect the nervous system (the webs woven by spiders are different from usual after drug use).
According to the way of life and predation, it can be roughly divided into webbed spiders and wandering spiders.
the main feature of a web-forming spider is its web-forming behavior. Spiders secrete mucus through the protrusions at the tip of their silk sacs, which can condense into very thin silk when exposed to air. The web made of silk is highly viscous and is the main predation means of spiders. For insects that stick to the internet, spiders will first inject a special liquid jujube digestive enzyme into their prey. This digestive enzyme can make insects coma, twitch and even die, and liquefy the body. After liquefaction, spiders eat by sucking. Spiders are oviparous, and most male spiders will be swallowed up by female spiders after mating with them and become food for female spiders.
Wandering spiders don't spin webs, but wander around or pretend to prey on the spot, such as tall-legged spiders, which are commonly known as "worm catching" (worm forehead) in Taiwan Province.
some spiders can make a balloon out of a net and float to other places with the wind.
For human beings, spiders are not food on the table, and they are even afraid to stay away. Lu Xun said, "The first person who eats crabs is admirable. Who dares to eat it unless he is a warrior?" Some people eat crabs, and some people must have eaten spiders. But it's not delicious, so later generations will not eat it "("Two Feelings of Spring "). But recently, some areas, such as Sukhumi, Cambodia, sell spiders as their dishes.
spiders mainly prey on small insects. The tarantula beside the water can prey on small fish and shrimp, the bird spider can catch birds (it is said, but there is no exact literature), and a 7.5-cm-long spider in South America can even prey on small rattlesnakes. Web spiders prey on their webs.
(1) The method of dismemberment:
When spiders hunt, they first paralyze their prey with the poison in their fangs, secrete digestive juice and inject it into their prey to dissolve it, and then suck it slowly, without missing anything.
(2) Self-made fresh-keeping bags:
Spiders are afraid of light and often make webs in places with light and ventilation. Spider silk can be used not only to trap prey, but also as a fresh-keeping bag. Spiders wrap the leftover food in a net for the next time.
(3) cleanliness:
spiders clearly divide the places where they eat, sleep and pull. Domestic spiders generally use the cage as a garbage station where they urinate and throw food scraps.
(4) Extremely delicate appetite:
Spiders have a strong sense of territory and should be kept separately. They only eat one or two meals a month and can fast for up to two months. The food is mainly insects such as crickets and Cao Meng. Just put a wet sponge in the cage to replenish it with water, and you can raise it to adulthood (about seven years) without changing the cage.
not all spiders are poisonous (among them, the spiders of the family Arachnidae are not poisonous)! And the toxicity is different. Usually, the pet spider on the market is relatively weak in toxicity, and it will not attack people actively as long as it is not intentionally teased. Even if you are bitten, your life will not be in danger. It has strong adaptability and does not need careful care. Spiders are the easiest pets to keep.
Spider silk is expected to be used to make high-strength materials, and experts from the Institute of Gene Biology of Russian Academy of Sciences are actively studying the use of spider silk to make high-strength materials. There is a cluster of spinners behind the spider's abdomen, which passes through the silk glands in the body. Protein mucus secreted by this gland can condense into extremely strong spider silk in air. According to the Moscow Youth League newspaper, experts from the Institute of Gene Biology of the Russian Academy of Sciences found that the hardness of this material is 9 times higher than that of steel with the same thickness, and the elasticity is 2 times higher than that of other synthetic materials with the most elasticity. Experts believe that after further processing, the above-mentioned spider silk materials can be used to manufacture light bulletproof vests, parachutes, protective materials for weapons and equipment, wheel tires, plastic surgery appliances and high-strength fishing nets.