gingkgo
Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead
Latin scientific name
Araneae; araneae
Another name
Networm, Flat Spider, Round Spider, Octopus, Xizi, Bos.
boundary
animal kingdom
door
arthropoda
morphological character
Spiders vary in length from 0.05 mm to 60 mm. The body is divided into chest and abdomen. Some species have breastplates at the back of the head and chest (some don't), and there are usually 8 monocular eyes (6, 4, 2, 0) at the front of the head and chest, arranged in 2 ~ 4 rows. There is a big chest plate on the ventral surface, and a lower lip between the two frontal lobes in front of the chest plate. The abdomen is not segmented, and the abdominal stalk evolved from 1 abdominal segment (the seventh body segment). The abdomen is mostly round or oval, and some have various strange-shaped protrusions. The ventral rotator evolved from appendages, and there are 8 primitive species, which are located slightly in the front; Most species have six spinnerets, which are located in front of the anus at the back of the body; Some species have four spinnerets, and there are many spinning tubes on the spinneret, which are connected with various silk glands, and the silk is spun from the spinning tubes. Sensory organs include eyes, various sensory hairs, auditory hairs, lyre and tarsal bones. [2]
White-fronted spider
Spiders have chitin exoskeletons all over their bodies, and their bodies are obviously divided into head, chest and abdomen. They are often connected with thin handles from the first abdominal segment, with no tail segment and no tail whip. Spiders don't have compound eyes, and they have six pairs of appendages on the head and chest. The first pair and the second pair belong to the cephalic appendage, in which the first pair is mostly 2 joints, the enlarged part at the base is a claw, the tapered part at the end is divided into claws, and the teeth are tubular. There are poisonous glands in the claws or head and chest, from which the venom is secreted. The second pair of appendages, called foot whiskers, are shaped like walking feet, but have only six joints. The base joint forms a jaw-shaped protrusion near the mouth, which can help feed, while the female spider's foot whiskers have little change, while the male spider's foot whiskers are specialized as reproductive auxiliary organs, which have the structure of storing and transmitting sperm, called limb-touching devices. The third to sixth pairs of appendages are walking feet, consisting of seven joints, with claws at the end and a cluster of bristles under the claws, which are suitable for crawling on smooth objects. [2]
Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead
Most spiders have poisonous glands, with claws and claws. Most burrowing spiders move up and down, but they prey on the ground, and spiders that web in the air sweep around like pliers. No tentacles, no wings, no compound eyes, only one eye, usually 8 eyes, but there are also 6, 4, 2 eyes, and some even have no eyes. As far as the color and function of eyes are concerned, they can be divided into day and night. [2]
The mouthparts of spiders are composed of claw limbs, jaw leaves, upper lip and lower lip, which have the functions of poisoning, catching, crushing food and sucking juice. [2]
Some spiders have clumps of sticky hairs under their tarsal claws, which have the ability to make spiders crawl on vertical and smooth objects. The spider that webs has several claw-like spines near the top of the hock joint, which are called secondary claws. [2]
The abdomen of most spiders is unsegmented. Whether there are external female organs (called reproductive organs) is an important feature to identify female species. There is a special rotator in the middle or back of the abdomen. Three pairs of rotators are called front, middle and rear rotators according to their landing positions. The top of the spinning machine is provided with a film spinning tube which is surrounded by fur. Different spiders spin different kinds of silk with different spinning tubes. The spinner of the rotating tube is also a rotating organ. For example, there are 966 on the spinning machine of Lepidoptera. There are 8 kinds of silk glands extracted from the body through spinning tubes. With the growth and molting of spiders, the size and number of silk glands are increasing. Spider silk is a kind of bone protein, which is very sticky, tough and elastic, and will harden when exposed to air after spinning. [2]
Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead
Androgyny, the male is smaller than the female, the male tarsal joints develop into acrobats, and the female has external reproductive organs after molting for the last time. [2]
There are three pairs of feet, which are divided into basal joint, trochanteric joint, calf joint, knee joint, tibiofibular joint, posterior tarsal joint, tarsal joint and tarsal joint (with claws on it). The foot is covered with bristles and has several sensory organs, such as fine hair (feeling airflow and vibration). After self-cutting, the next molting can be regenerated. Under 8 in one eye. Some foot muscles and palatal muscles are attached to the intrathoracic bones of the head and chest. There is a slender abdominal handle between the head and chest and abdomen. Because of the belly handle, the belly can swing freely when rotating. The nervous system is completely concentrated in the head and chest, and the brain (superior pharyngeal ganglion) is in the pharynx and inferior esophageal ganglion. Cracked sensory organs are scattered around the body or near the joints of the feet to control vibration or hearing. [2]
The abdomen is not segmented, and there are digestive system, heart, reproductive organs and silk glands. When eating, first spit out digestive juice, digest it in vitro, and then inhale liquefied food. It has both book lung and trachea, but only book lung in Orthopalatine suborder and trachea in Palatina. In addition to arachnida, there are poisonous glands, which are located under claws or crustaceans. Poisonous gland tube passes through the opening of claw limb, close to the tooth end. Poisonous glands may originate from auxiliary digestive glands. The venom glands of many species of spiders are digestive enzymes, and some species can subdue prey and even fight predators (including vertebrates). [2]
classify
According to documents, there are 38,265,438+0 genera and 42,055 species of spiders in the world (2065,438+00), and there are about 3,800 species recorded in China, belonging to 67 families. ARANEAE * * has 14 orders, of which 5 orders are extinct and 7 orders are found in China. [3]
There are spider 1 10 families, 3859 genera and 4275/kloc-0 species (subspecies) in the world, and there are more than 3800 species in 67 families in China. There are many excellent spider species that can be cultivated artificially. In order to let beginners know the characteristics and sources of different spiders, several species are introduced for reference. [3]
Bird-catching spider: brown body, very large, generally about 7 cm long, and some can reach 10 cm long. It has the ability to build its own living nest, burrowing in dry fields or overgrown places, lurking in caves during the day and hunting at night, with strong reproductive ability and high poison production. Each female spider produces 300-500 eggs a year, and every 200 bird-catching spiders can lift them once. [3]
China tarantula: The whole body is densely covered with fine black, white and yellow hairs, and the head, chest and back are brown with yellow-brown longitudinal spots in the center. The front is wide and the back is narrow, and the middle fossa is obvious, with a body length of 3 ~ 4 cm. As a burrowing spider, it mostly burrows and nests in crops fields such as cotton, wheat and soybean in plain areas. Produced in Shaanxi, Shandong, Henan and other provinces. [3]
Bangluo Bride Spider: Spider is 3 ~ 5cm long, with dark brown head, black chest and back, black claws and yellow limbs. There are yellow short rod spots in the first half of the center, and yellow lattice spots in the second half. It often moves in orchards, rice, corn and other farmland crops and forests. Especially in forest areas, it is the most widely distributed, and often forms a complex three-gold net on plants or trees. It is a web spider, good at preying on all kinds of flying insects. Each female spider breeds 800 ~ 900 young spiders every year. Every 400 ~ 500 spiders can produce 1 g venom. This kind of spider can be found in many parts of southern China. [3]
White-fronted Cancer Spider: This kind of spider has a short and flat body, and can run sideways with its feet spread out from left to right, so it is relatively large. It is one of the common spiders indoors, easy to walk and easy to escape. It lays eggs from May to June, and each female spider can breed 500 to 600 young spiders. 600 spiders produce 1 g venom at a time. This spider is distributed in Henan, Shaanxi, Sichuan, Jiangxi, Guangxi, Hunan, Hubei and other provinces. [3]
Scleroderma striatum spider: The spider is 3-4 cm long, the female spider is yellow-brown, the head, chest and back are bifurcated, and the claws are long columns. The chest plate is gray-black, with eight small gray spots around it. Spiders are burrowing, their nests are tubular, and there are radial spider silk around the holes. Each female spider breeds 800 ~ 900 young spiders every year, and every 800 ~ 1000 spiders can produce poison 1 g. This spider is mainly distributed in Shaanxi, Shandong, Sichuan, Jiangxi, Guizhou, Yunnan and other provinces. [3]
population distribution
Araneae is divided into two suborders: ① There are more than 20 species of 1 family in China; ② Spinning suborder (about 107 family, nearly 40,000 species). [3]
Some species of Arachnidae
Among them, the post-spinning suborder is divided into A: Protospider suborder (about 14 family, 1500 species); B: New Araneae (about 93 families, more than 38,000 species). [3]
Spiders are natural enemies of many agricultural and forestry pests and play an important role in biological control. Protecting and utilizing spiders has become an important part of biological control. Spiders can be used as medicine to treat diseases such as proctoptosis, sores and bromhidrosis. The venom of a few spiders, such as the black widow, is harmful to people and animals. Burrowing tarantulas of the Tarantula family are distributed in Europe and Asia, and are also common in Xinjiang, China, and their poison can kill people and animals. Some spider toxins contain hemolytic enzymes, which can cause local necrosis and ulceration of wound tissue and spread around. [3]
By the middle of19th century, spider research had developed rapidly. By the date of 20 1 1, 65438+2, 3 1, there were 3859 genera and 4275 1 species (subspecies) in the world. Because of the different geographical and ecological conditions around the world, the distribution of spiders is extremely uneven. These spiders can be roughly divided into three types: safari spiders, cobwebs spiders and cave spiders. The first kind will forage everywhere, and the second kind will wait for rabbits after weaving a net. Most people keep the third kind as pets: cave spiders. They like to hide in sand or holes and make a net at the hole. The net itself is not sticky, and it is purely used to sense the size of prey and hunt.
Living habits
Because spiders are highly sensitive to the changes of environmental factors including habitat structure [4], habitat type [5], wind, humidity and temperature [6], they can be used as indicator groups to monitor the changes of habitats and biodiversity, and their species composition and quantitative changes become important indicators for environmental monitoring, which can well reflect the process of environmental changes and its impact on biodiversity. [7]
Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead
Eating habits
Spiders mostly feed on insects, other spiders and multi-legged animals, and some spiders also feed on small animals. Jumping spiders have good eyesight and can dive close to catching prey within 30 cm and pounce on it. Crab spiders wait for prey on flowers close to their body color. The ground spiders who make holes in the soil build a cave lined with silk, which has a living cover that opens at night to prey on insects that pass through the hole. Funnel spiders weave funnel nets, which will cause vibration when catching insects; Spiders themselves live in silk tubes with narrow ends leading to plants or cracks. [8]
Most circular spiders weave the largest web with the least silk, just like air filters, trapping insects that can't see the filaments and have weak flying ability. Although the net is complicated, it can be woven in 1 hour, usually before dawn. If the net is destroyed in the process of predation, weave a new net. When weaving a web, the spider releases traces and floats in the wind. If the free end of the spider silk doesn't stick to anything, the spider will pull it back and eat it. If the silk sticks firmly to something (such as a branch), the spider will cross the silk bridge and reinforce it with silk. The spider took a thread in the middle of the bridge, fell on a thread and hung down, sticking to the ground or another branch. The spider returned to the center, and Radogan radiated from the center of the web. Then, the spider crawled back to the center of the net and pulled temporary spiral wires from the inside out, with a large spacing between the spiral wires. Then the spider climbs to the outermost periphery and places a sticky and dense insect-catching spiral wire from the outside to the center of the web. While knotting, eat the dry spiral silk knotted before, which is not sticky. After the web is finished, some spiders tear off a silk (signal silk) from the center of the web and climb into the leaves in the corner of the web to hide.
If an insect casts a net, it can hear the news and eat through the vibration of the signal line. Some spiders stay head down in the middle of the web, waiting for their prey. When there is prey, they first wrap it in silk, then take a bite 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 bitten first and then tied with silk thread. Some spiders * * * use cobwebs. For example, the social funnel spider (Agelena conso ciata) in Gabon will make a big web, and hundreds of spiders will hunt together. Spiders may play an important role in controlling the number of some insects. The neurotoxicity of several poisonous spiders is toxic to people. The process of weaving webs has aroused the interest of the scientific community and has been used to study drugs that affect the nervous system (after using drugs, spiders weave different webs).
Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead
According to the way of life and predation, it can be roughly divided into web 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 top of their silk sacs, which can condense into very thin silk when exposed to air. The web made of silk is very sticky, which is the main predation means of spiders. For insects that stick to the web, spiders will first inject their prey with a special liquid jujube digestive enzyme. This digestive enzyme can make insects coma, twitch and even die, and liquefy their bodies. After liquefaction, spiders feed by sucking.
Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead
Wandering spiders don't weave webs, but wander around or pretend to hunt prey on the spot, such as tall-legged spiders, commonly known as "worms" in Taiwan Province Province.
Some spiders can make balloons out of nets and float to other places with the wind.
way of life
Spider lifestyles can be divided into two categories. Namely hunting type and settlement type. Hunter-gatherers are spiders that hunt everywhere. They have no place to live, and they don't make webs, dig holes or build nests at all. Arachnida, Arachnida and most tarantulas. Settled type: some make nets, some dig holes, and some build nests as permanent residences. Such as wall money, stone spiders and so on. Spiders seem very polite. Everyone who lives independently keeps a certain distance and does not invade each other.
***3 sheets
cobweb
Compared with ordinary insects, spiders have a long life. Most spiders complete a life cycle, usually 8 months to 2 years. Male spiders have a short life span and die soon after mating. Others, such as water spiders and cunning spiders, can live 18 months, cave tarantulas can live for 2 years, cancer spiders can live for more than 2 years, and bird-catching spiders can live for 20 to 30 years.
Spiders live on silk, which is secreted by silk gland cells and is a viscous liquid in the gland cavity. After being drawn out by the spinning tube, it will condense into filaments when it meets air. The specific gravity of silk is 1.28, which is strong and elastic.
Spiders in the net holes stay in the net during the day and at the mouth of the cave at night, waiting for opportunities to hunt or go out for food. The male spider dug a shallow hole under the clod, the burrowing tarantula dug a vertical deep hole in the ground, and the dancing spider added a living cover to the hole. This kind of valve consists of multiple layers of silk. The hole depth of the giant spider is 1 m. This kind of spider is very small and poisonous. Once bitten by a cave rabbit, he died in four minutes.
When young spiders start to live in webs, if the spider silk can't attach to anything and there happens to be upward airflow, it will fly in the air and with the wind. For example, arachnida, tarantula, arachnida, jumping arachnidae, etc. All have the ability to fly. Spider Flying: If a spider named balloon is interested in balloons made by humans, it will also despise artificial balloons. This spider will weave a silk thread under the sunshine on a windless summer day, and it will stretch straight into the air under the warmth of the sunshine. Just like a soaring bird, it will find a place with updraft before rotating, or it will rotate first and then use the surrounding hot molecules to form updraft. I don't know, but in any case, the silk thread will keep rising and then rising until the spider knows that it can support itself and then release it. Its heavy body is supported by a silk thread that is less than its weight 1%. At the moment, the standardization conditions are produced by all incredible fine adjustments, including the adjustment of sunlight, wind, length and weaving thread length, which is very effective for avoiding cannibalism and high evacuation density.
After careful calculation, an expert found that the strength of spider silk is five times that of steel wire with the same volume. After the spider has made a web, it crouches in the center of the web, "waiting for the rabbit"-waiting for the flying insects to trap itself. A small leaf and a thin withered stalk landed on the spider web, and the spider trembled and stopped; However, a careless flying insect hit the net, and the spider climbed up excitedly, spewing sticky silk to bind its prey, anesthetizing it with fangs, and then sucking it after it was organized into liquid. How does a spider know there will be something delicious in its mouth? It has a crack-like vibration sensor on its leg. Dead leaves don't move when they hit the net, so the spider just shivers at the moment when it hits the net. If a flying insect hits the net, it will definitely struggle and send a vibration signal to the spider. Strangely, the two kinds of flying insects that hit the net have completely different reactions: if it is a fly, it will come and bind it immediately; If it's a bee, the spider will stay put. Are spiders afraid of bee stings? That's not true. Scientists have found that spiders are most sensitive to vibrations with a frequency of 40-500 Hz, and the frequency of flies flapping their wings is just within this range, while the frequency of bees flapping their wings exceeds 1000 times per second, so they will not attract the attention of spiders. It is found that cobwebs are very important to spiders' lives. Spider webs are not only traps and restaurants for this animal to catch prey, but also their communication lines, streets, wedding beds and nursery rooms. Spiders are crawling back and forth on cobwebs. Why don't they get stuck by sticky silk? Usually, spiders use dry silk as a runway. When they stick silk, their eight legs secrete an oil as a lubricant, which makes them advance and retreat freely on the internet.
Spider nesting
Spiders' display of motherhood is even more impressive than their talent for hunting. Its nest is a silk bag and its eggs are laid in this bag. Its nest is more mysterious than bird's nest. It is shaped like an inverted balloon, about the size of pigeon eggs, with a wide bottom, a narrow top and a flat shape, surrounded by a clam-shell edge. On the whole, this is an egg-shaped object supported by several wires.
High-legged spider
The top of the nest is concave, like a bowl covered with silk. The rest of the nest is covered with a thick and delicate layer of white satin, dotted with some ribbons and some brown or black patterns. You can immediately guess the function of this layer of white satin. It is waterproof and will not be soaked by rain or dew.
In order to prevent the eggs inside from being frozen, it is not enough to just keep the nest away from the ground or hide in dead grass. There must also be some special heat preservation equipment. Cut this layer of rain-proof satin wrapped outside with scissors and have a look. A layer of red silk was found under this. This layer of silk is not fibrous as usual, but a fluffy bundle. This substance, softer than swan velvet and warmer than a stove in winter, is a comfortable bed for future spiders. The little spider will not be attacked by cold air in this comfortable bed.
***5 sheets
Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead
There is a hammer-shaped bag in the center of the nest. The bottom of the bag is round and the top is square, with a soft cover on it. This bag is made of very soft satin and contains spider eggs. Spider eggs are tiny orange particles that gather together to form a pea-sized ball. These are the treasures of spiders, and the mother spider must protect them from cold air.
When it makes a bag, it slowly walks around the circle and releases a silk at the same time. Its hind legs pulled the silk out, stacked it on the silk in the last lap, and added it round and round, thus weaving a small bag. The bag and the nest are connected by silk thread, so that the mouth of the bag can be opened. The bag is just big enough to hold all the eggs, leaving no gaps, and I don't know how Mother Spider can master it so accurately.
After laying eggs, the spider's silk sac will start to operate again. But this job is different from before. I saw it put down its body to touch a certain point first, then lifted it up, and then put it down to touch another point, so it was here for a while, there for a while, and it was up and down for a while, with no regularity, while its hind feet were pulling the released silk. The result of this kind of work is not to weave a beautiful satin, but to weave a messy and intricate net.
Then it shoots a reddish-brown silk, which is very soft. It pressed the silk tightly with its hind legs and wrapped it outside the nest.
Then it changed the material, released white silk, wrapped it outside the nest, and added a white coat outside the nest. Moreover, the bird's nest at this time is already like a small balloon, with a small upper end and a large lower end. Then it releases silk in various colors, red, brown, gray and black, which makes you dazzled. It decorated its nest with this gorgeous silk thread. The whole work is not finished until this step is over.
What a magical cotton mill the spider runs! Relying on this simple and eternal factory-it can alternately do rope rubbing, spinning, weaving, ribbon and other work, and all the machines in it are just its hind legs and silk bags. How does it change "work" at will? How does it extract the silk of the color it wants at will? We can only see these results, but we don't know the mystery.
After the nesting work was completed, the spider head slowly walked away without looking back. Never come back, not because it is cruel, but because it really doesn't need to worry anymore. Time and sunshine will help it hatch eggs. Besides, it has no energy to worry about. When building a nest for its children, it has used up all the silk, and there is no more silk for itself to prey on. Besides, it has lost its appetite. Aging and fatigue made it die peacefully after a few days. This is the end of the spider's life in that box, and it is also the inevitable destination of all spiders in the tree.
Reproductive habit
Male spiders weave a sperm net before mating, produce a drop of liquid containing sperm from the reproductive hole to the sperm net, and then suck the sperm into the limb-touching device. Some have courtship during mating, such as tarantulas and jumping spiders waving their beards. The males of stolen spiders in Europe give the flies wrapped in silk to the females and mate with them when they eat; When you can't find flies, use small stones instead. During mating, most male spiders insert their left whisker limb into the left opening of the female spider's reproductive plate and their right limb into the right opening. After the sperm enters the reproductive plate, it moves into the seminal vesicle communicating with the fallopian tube, and the egg is fertilized in the process of being discharged from the fallopian tube to the reproductive hole. Some male spiders refill the connector with semen after mating and mate with the same female spider again. After mating, some kinds of male spiders will coat a layer of secretion (reproductive plug) on the reproductive plate of female spiders to prevent female spiders from mating again. Some male spiders will be eaten by female spiders after mating, but this is not common. Black widow male spiders die a few days after mating, and occasionally they are killed by female spiders because they are too weak after mating.
Conch
Why are male spiders willing to sacrifice themselves? Andre, a Canadian scientist, cracked the secret in an article in the American magazine Science. She marked the male red-backed spiders with paint to see how they found the female spiders' webs, but found that most male spiders died before finding the other half.
Like other kinds of male spiders, they don't eat or drink when they are mature. They can only survive on the energy stored before, and they can't stand the torture of long journey at all. The thin red-backed male spider stays in his own web. Once away from the safe haven, the ants are invincible.
In the end, only 20% of male spiders can successfully reach the female spider's web-Andre believes that it is because of the hard-won opportunity that male spiders are willing to give their lives for future generations.
When male red-backed spiders insert sperm organs into female spiders, they will stand upside down with their forelimbs as fulcrums and let their bodies hang down from female spiders' mouths. When it was injected with semen, a female spider 200 times bigger than it began to chew its tail.
Even more amazing, the male spider still has a chance to escape. It has two mating organs, one of which can escape the clutches of death and return to life after fertilization. But within 20 minutes, the male spider usually returns to the mother net for a second mating, and this time, the female spider will never show mercy again.
Why did the male spider commit suicide? Stay in the castle peak, don't worry about burning wood?
Because the female red-backed spider stored her sperm in a special organ, Andre removed the organ and tried to interfere with the mating time of the red-backed spider by experimental means.
With the help of a microscope, Andre counted the number of sperm received by female spiders after mating, and found that the mating time is closely related to the number of sperm delivered-the male spiders who mated with female spiders twice delivered more sperm 1000 than the male spiders who mated only once. It turns out that for 1000 sperm and for the continuation of the whole race, the male spider gave his life-this is the most cost-effective choice for the weak male spider, because it can't guarantee the strength to find another female spider to mate alive.
Andre finally understood that the spider had no love for The Secret Behind.
Some female spiders mate only once, while others can mate with multiple males in succession. After mating, the female spider produces an egg bag with several to 1000 eggs, or several egg bags, each containing fewer eggs. Some species die after giving birth to the last egg bag or caring for young spiders. The average life span of this female spider is 1 ~ 2 years. The life of straight chelate is 20 years.
Some primitive species' egg bags are composed of several layers of silk, which are spherical or disc-shaped and attached to stones. Some female spiders guard the egg bags. Tarantulas carry egg bags in their claws or during rotation. After hatching, the young tarantula climbed onto the back of the female spider and left in about 10 days. Some female spiders take their young spiders to bask in the sun, while others feed their young spiders. There is a spider in Europe. The female spider died when the young spider began to feed and became the food for the young spider. Young spiders, like spiders, mature after molting several times. The female spider molts 6 ~ 12 times and the male spider molts 2 ~ 8 times. Some have molted 1 ~ 2 times before hatching. It takes 3 ~ 4 years for the straight chelate to mature. Most of them overwinter with underage spiders. Development and molting are controlled by hormones. Many young spiders can climb to the leaves or treetops, straighten their bellies and let out a few strands of silk to spread by the wind.
The female spider spins silk to form an egg bag, which contains fertilized eggs, and the egg bag is attached to the net (spider), or produced under the stone or on the leaf surface. Some female spiders guard egg bags, and some carry them with them. The young spider that hatched the eggshell stayed in the egg bag for a few days and peeled 1 ~ 2 times in the bag. Young spiders molt 4 ~ 10 times before maturity. Spider silk plays an important role in spider's life. Weaving webs is the instinct of many kinds of spiders. There are many kinds of nets, and the methods of weaving them are different. Many kinds of spiders, especially young spiders, can fly with silk.
Spiders lay eggs, which are usually wrapped in silk bags. Females protect and carry egg bags in different ways, or put them on the net, under rocks, on branches, or put them in their mouths and breasts. For incomplete metamorphosis, the abdomen is still segmented in embryonic stage, and whether there is a net or not is alive. There are circular nets, dish nets, funnel nets, triangular nets and irregular nets. There is a folk song "Little Zhuge Liang, sitting alone in the army account, catching flying generals in the Eight Diagrams Array", which vividly depicts the phenomenon of spiders netting insects.
Spiders are not only hermaphroditic, males are smaller than females, but also have different colors. For example, the male of the jumping spider family is bright and the female is dark. The males of the cancer spider family have red stripes on their backs, while the females are all green.
Male spiders mature sexually earlier than female spiders, and male spiders appear for a short time. Most of them are female spiders. Spiders have a unique way of mating. For example, after mating, those who can escape being killed by the female spider can mate again.
Before laying eggs, the female spider will make a "puerperal" with silk. Lay eggs on it and cover it with silk. And weave the egg bag into a fixed shape. Generally, a female spider only lays one egg bag, and some also lay multiple egg bags, such as 5-6 spiders, 13 spiders. The number of eggs laid by a female spider can range from a few to several hundred, such as 60-720 spiders of certain species of Arachnida, 1000 spiders.
The young spiders hatched from the egg shell still remain in the egg bag, and they have to molt in the egg bag 1 time before leaving the egg bag. Tarantulas are called nanny spiders because they not only hunt with egg bags, but also have the habit of carrying larvae after hatching. Some female spiders die immediately after being woven into the egg bag, some young spiders leave the egg bag and continue to live for a period of time, and some hatched young spiders are killed alive as food.
Before the mature stage, spiders molt many times with their growth, and the molting times and intervals are very inconsistent. Generally speaking, little spiders shed their skin 4-5 times in their lifetime; Medium-sized spiders are about 7 ~ 8 times; Okumo molts about 1 1 ~ 13 times, for example, the male spider of red spider molts 5 times and the female spider molts 7 times.
Value meaning
Spider silk is expected to be used to make high-strength materials, and experts from the Institute of Gene Biology of the Russian Academy of Sciences are actively studying the use of spider silk to make high-strength materials. There is a cluster of spinnerets 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 the air. According to the Moscow Communist 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 most elastic synthetic materials. Experts believe that after further processing, the above spider silk materials can be used to manufacture light body armor, parachutes, protective materials for weapons and equipment, wheel tires, plastic surgery appliances and high-strength fishing nets. [9]
artificial feeding
Because spiders are fierce, carnivorous and have the habit of killing each other, it is easy to succeed in raising them alone, but it is difficult to raise them in groups. Because spiders have diverse diets, are hungry-tolerant and have strong vitality, they can succeed as long as they guarantee the three basic conditions of food, water and shelter. It is observed that the tarantula pseudoannulata, which is about 1 cm long, preys on 7 ~ 12 planthoppers, leafhoppers and flies every day. The tarantula pseudoannulata can endure starvation for 34 ~ 1 12 days with water and no food supply. This kind of spider has strong hunger tolerance, which is related to its large appetite. Generally, the higher the temperature, the worse the hunger tolerance. [ 10]