Not everyone knows how many legs a spider has, because it seems like there are a lot of them because of fear, the answer is always clear - 8. There are many species of “arachnids” on our planet. In addition, some species are very poisonous, and many of them are completely safe.
It should be noted that there are species that live in human homes as pets. Why not, especially since they eat little and leave virtually no waste.
Spider legs structure
The legs, or as they often say paws, vary in length and thickness depending on the type of spider. But their structure is the same. The segments, also known as parts of the leg, consist of a number of parts:
- pelvic;
Spider structure.
- trochanter;
- femoral part;
- knee part;
- shin;
- calcaneal segment;
- paw.
claw
There is a claw segment that is not separated from the paw, so they are not separate.
Hairs
The hairs that completely cover the legs act as an organ of touch.
Length
The first and fourth pair of legs are the longest. They are walking. The third ones are the shortest.
Hairline
The body of the flycatcher is covered with a hard chitinous armor shell. Its name is exoskeleton.
It performs several functions at once:
- protects internal organs from mechanical influences;
- serves as a buffer between nature and the predator’s body;
- strengthens most muscles;
- plays the role of a supporting frame.
Hairs and bristles grow on the exoskeleton, performing protective, sensory and tactile functions. Webmasters have no ears. They hear using hairs located on their legs. By catching waves emanating from a sound source, the spider quite accurately determines the location of the object. The number of hairs on the sole of the paw reaches several thousand.
The nervous system of a predator includes only 2 nerve ganglia, but the volume of the brain occupies from 20 to 30% of the cephalothorax. Surprisingly, these creatures can even distinguish colors, and special sensitive hairs on their legs help them recognize odors. Arthropods also have chemically sensitive hairs on their limbs. With their help, the fly catcher determines whether his prey is poisonous.
The life of a spider is eventful. To feed, he has to constantly weave nets and catch prey. Over time, the exoskeleton wears out, and the predator replaces it by molting. Along with the chitinous armor, the hairline also changes. If the spider's leg was previously torn off, a new one will grow during the molting process.
Limb functions
The abdominal limbs are walking. They are long and allow spiders to move quickly and jump high with spring. The spider's movement looks smooth from the outside.
This is possible due to the fact that pairs of legs have certain functions: the front ones pull up, and the back ones push. And from different sides there is movement in pairs, if the second and fourth pair are rearranged on the left, then the first and third are on the right.
Interestingly, when they lose one or two limbs, spiders also move actively. But the loss of three legs is already a problem for arachnids.
Classification
There is no uniform classification system for spiders. One can only correlate their specific types by density of distribution, rarity of a particular species, safety or threat to human life, and size.
Safe spiders
This species includes representatives of the animal world that do not harm people. They are either unable to bite through the skin at all, or their venom does not pose any threat.
These arachnids include:
- crosses,
- tarantulas,
- haymakers (mowers),
- horses,
- brownies.
Cross spider
Deadly poisonous
In most cases, spiders do not pose any threat to humans. Especially if you don't try to deliberately anger him. But there are also those with whom it is better not to meet.
Arachnids that are truly poisonous and dangerous:
- karakurt,
- black Widow,
- Brazilian Runner Spider,
- banana Spider,
- brown recluse.
Brown recluse spider
Rare
Some spiders can be found everywhere, while others are very rarely seen.
Such distinctive arthropods include:
- nephila-goldweaver,
- baboon spider,
- sydney spider Funnel Web,
- Colombian purple tarantula,
- phalanx spider,
- giant crab.
Golden spider
Little ones
Like all representatives of the animal world, spiders tend to vary in size. And if large arthropods evoke fear and disgust, then baby spiders can even evoke tenderness.
These babies include:
- anapistula,
- patu digua,
- side walker,
- Kipling's Bagheera
- Abacarus histrix.
Sidewalk spider
Large
And next to these little ones live real giants who are impossible not to notice.
Particularly large species:
- tarantula Theraphosa Blonda,
- orb-weaver-nephila,
- tarantula,
- giant crab,
- banana spider.
Tarantula
Pedipalps and chelicerae
The entire body of the spider consists of two parts: the cephalothorax and abdomen. Above the mouth opening there are chelicerae, covering the fangs and holding prey, and next to them are the pedipalps. These appendages are so long that they are confused with limbs.
Pedipalps. Processes near the chewing outgrowth, which serve two purposes: orientation in space and fertilization of females.
Chelicerae. They are like little claws that inject poison, grind and knead food. They pierce the body of the victim, they are mobile from below.
Spider legs.
Hairs
There are hairs along the entire length of the spider's legs. Depending on the type, they can differ in structure; they can be smooth, protruding and even curly. On the heels of the fourth pair of legs there are thickened bristles in the form of a comb. They are used to comb webs.
Spider hairs.
Interesting Facts
In Russia there are over a thousand types of arthropods. There are also dangerous varieties among them. It is noteworthy that all web masters are poisonous, but few pose a danger to humans. The most toxic of them are Karakurt and South Russian tarantula. They bite only if they feel a threat coming from people, so you should not provoke them to show aggression.
The lifespan of spiders varies. House flycatchers live from several months to a year. An ancient sign says that they appear in homes where there is money. In nature, arthropods live longer. Some representatives of Africa and South America live up to 15 years, and a female tarantula can live in a favorable environment for more than 20 years.
As for height, the champions are Goliath, who grows up to 30 centimeters, and the female Brazilian giant tawny tarantula, whose leg span reaches 26 centimeters. The most toxic in the world is also the representative of Brazil - the Traveling Spider. The result of its bite is paralysis and, less commonly, death. Children are especially vulnerable.
The respiratory organs of spiders vary and look quite peculiar. Some breathe using the trachea. Oxygen is delivered to the tissues through special openings (spiracles). Others have lung sacs that, thanks to the plates, resemble book pages.
The blood of arachnids is transparent, turns blue in the air and has nothing in common with human blood. Accordingly, these predators do not have a circulatory system. But some of them are capable of jumping a distance exceeding their body length by 50 times. You can meet fly and mosquito catchers everywhere except Antarctica, where there are extreme frosts.
How long is a spider's leg?
The length varies from minimum to maximum depending on living conditions and lifestyle.
Haymaker.
Harvesters, often thought to be spiders, are actually false spiders with very long legs and a gray body.
There are several record holders:
- Brazilian wandering spider - more than 15 cm;
- Baboon - more than 10 cm;
- Tegenaria - more than 6 cm.
It happens that even in the same species of spider, under different living conditions, the size and length of the legs vary.
Difference from insects
The spider belongs to the class of arachnids, it is not an insect . Characteristic features of this type:
- The main difference between arachnids and insects is that the last 6 legs are located on the chest, and not on the cephalothorax. In addition to external differences, animals have different structures of internal organs.
- Centipedes are also not insects, since they belong to a separate species.
- If we compare the body structure of arachnids with other creatures, it can be more closely related to a scorpion.
Spiders that live in apartments cannot harm the human body. You need to pay attention to sanitation conditions. Animals live in houses where there is enough food to remove them, it is necessary to get rid of the main cause of the invasion.
About arachnophobia
Science knows more than 40 thousand species of spiders. Some stand out for their size, others for their toxicity, and others for their color. But at the same time, for the majority, the appearance of absolutely all arachnids is unattractive, and some experience panic fear of them. Such people are called arachnophobes.
This is interesting! Statistically, the fear of spiders is much stronger than the fear of guns and flying in airplanes!
But why are people afraid of spiders? After all, if you look at it, the arachnid has much more reasons to fear a person - he has much less chance of causing us any harm than we have in relation to him. Thus, the phobia itself seems somewhat irrational.
There is a theory that the fear of spiders dates back 350 million years ago, to a time when humans did not yet exist. Fossil arachnids were mostly poisonous and posed a serious threat to primates. As a result, the latter developed a reflex of situational readiness - when a spider appeared, they were forced to hide with lightning speed. Over time, the number of deadly species became much smaller, but the instinctive fear remained. Thus, it turns out that arachophobia developed as part of human evolution.
This is interesting! Arachnophobia is unknown to some peoples, mostly uncivilized ones - some, including children, can stroke quite large spiders with complete ease, others even eat them!
A little about nutrition
Quite often, people are sincerely surprised and cannot understand what spiders eat in their apartment, where there are no insects. In this case, it is important to remember one thing - even if you are sure that no one lives in your house except you, the appearance of spiders always indicates the opposite.
If a spider came into your house and wove a web in it, it means that there is a victim nearby that can fall into it. You may not see these small insects, but at least someone definitely lives in any apartment (provided that you do not chemically disinfest it every week).
Spiders living in apartments are insectivores and eat almost everything with legs, antennae and wings:
- silverfish can live quietly under your bathroom;
- in the kitchen where there is a vase of apples, tiny fruit flies can settle;
- food pantries often contain various beetles that eat cereals, flour, etc.;
- in addition, it could be flies and mosquitoes, insect larvae and other spiders accidentally flying in from the street.
How many fingers does a chicken have?
Fine
The usual number of fingers for hens and roosters is four. Three of them look forward, one looks back. This position allows individuals to maintain balance.
You can find animals with a large number of fingers. A rooster with a spur is often mistaken for a “five-fingered rooster.” Although it is formed from a hard growth, it cannot perform the functions of a finger.
Pedigree trait
There is a breed of chickens whose characteristic feature is the presence of five fingers. This is a fireball.
The homeland of birds is France. Initially, the breed was bred only for eggs and meat. But today it is considered decorative and participates in various exhibitions.
A chicken with four fingers is immediately discarded. Roosters of this species have spurs, which is why they are often mistaken for “six-fingered”. A full description is given in the article “Description of the Faverol chicken breed.”
Deviations
Another common reason for the presence of “extra” fingers in chickens and roosters is genetic abnormalities.
This happens when closely related chickens reproduce multiple times. In this case, there may be more than five fingers. Their number will also not be the same on different paws.
Such chickens are not considered a reject. Their productivity is not inferior in terms of indicators to “ordinary” representatives of their breed.
But you should not use chickens and roosters with genetic abnormalities in further breeding. Otherwise, the next generation will differ even more from the norm.
Execution cannot be pardoned
There are several signs that tell what the killing of a spider promises, and there are even some that contradict each other. But today we will move away from popular beliefs and look at several theories that, as it seems to us, are ways to explain why you should not kill spiders.
- According to legend, once upon a time a spider's web saved a man's life. He was persecuted and, forced to flee, hid in a cave, which was almost completely entangled in spider webs. The pursuers were never able to find the fugitive; they didn’t even bother to examine the cave - there were so many cobwebs in it.
- The second version, which tells why you should not kill spiders in the house, is based on their active use in folk medicine of past times. In ancient times, healers mainly used various decoctions and infusions to heal the sick, to which they added not only herbs, but also insects. Often the role of a healing “ingredient” was a spider, ideally poisonous. They treated with poison, so killing a spider without any serious purpose promised the rapid development of the disease.
- The third legend says that spiders attract happiness - it gets entangled in their web and remains in the house. And the owner of the fishing nets, who has settled in a residential building, is a symbol of good news and prosperity. For this reason, killing a spider means driving away happiness from the house - there will be no one to spin the web and all the good things from the house will soon “fly away” along with the last silk threads.
Small house spiders are not capable of causing harm to human health
And if there are several of them, then this is a reason to pay attention to the cleanliness of your own home. In this situation, it is not the spiders that should be destroyed, but the reason why they ended up in the apartment
Remember, spiders will always live where there is food for them.
For many people, spiders cause fear and some kind of hostility. I treat them with indifference. I won’t say that I’m afraid of them, but I don’t feel love for them either. Outside my window there is a tree with lush foliage; in the summer, one small spider settled there. One day I was watching him and noticed some peculiarities. I think you will also be interested in learning about them.
