Don't touch that spider. You may wonder why spiders become our friends because they destroy so many insects. Insects, including the most powerful enemy of human beings, will make it impossible for us to survive in this world.
They will devour all our crops, kill our sheep and cattle, if not to protect us from insect eating animals, We owe a lot of birds and beasts to eat insects, but together they kill only a fraction of the amount destroyed by spiders. Unlike other insectivores, spiders do the least harm to us, that is to say, spiders do no harm to our property. Spiders, like many people, are not insects.
Even people who have little to do with them can see the difference at a glance, because spiders always have eight legs, and insects never have more than six. How many spiders are involved in the work for our benefit. A spider Research Authority has conducted a census of spiders in a meadow in southern England.
He estimates that there are spiders in one acre of land, just like all kinds of spiders in football field, spiders have been busy killing insects for at least half a year. It is impossible to know how many insects they have killed, but they are hungry animals, and it is estimated that spiders do not weigh more than all insects in the UK in a year.
Spiders are carnivorous invertebrates with eight legs and two body parts without wings. They are often mistaken for insects, but all spiders have legs. Unlike insects, spiders usually have spinning organs at the back of their bodies.
They use these organs to weave cocoons for eggs or traps and webs. Because preya is any member of the Araneae Araneae, Araneae is divided into three groups They are: armyworm suborder (primitive Araneae, Araneae, Araneae, modern Araneae) and mesothelial Araneae, which contains the Araneae Araneae and includes burrowing spiders rarely seen in Asia. All spiders are carnivores.
They eat other kinds of arthropods, including mites, crustaceans, mice, skinks and even other spiders. The study of spiders is called Arachnology, although it is often included in more general entomology.
Araneae spiders (Araneae) are respiratory arthropods with eight legs and fangs that inject venom. They are the largest order of the arachnids and seventh among all other kinds of organisms. At least all species of spiders have been recorded in all parts of the world, except for the arachnids, which have been recorded in the Antarctic.
However, the scientific community has always been divided on how to classify all these families. From an anatomical point of view, the difference between spiders and other arthropods is that the common body parts of spiders fuse into two arthropods, namely the head, chest and abdomen, and are connected by a small cylindrical pedicel. Unlike insects, spiders, except for the most primitive intergroup skin, have no With antennae, the spider's nervous system is the most concentrated of all arthropods, because all of their ganglia are fused into one piece in the head and chest.
Unlike most arthropods, spiders have no extensors, but stretch by hydraulic pressure.