Written By: Anderson_Pro
Spiders belong to the largest phylum in the animal kingdom of Arthropoda and the class of Arachnida group. They have eight legs with well-developed chelicerae, which turn into fangs to inject venom into their victim’s body. Together, spiders make up the largest population of arachnids and rank seventh in the number of species found in the world as compared to other organisms. There are more than 34,000 different recognized species in the world. They’re not insects, but like insects, they are made up of two different parts that are bound to each other by a thin stalk. The two sections are part of the head and part of the stomach. There are eight eyes and four appendages on the face. There is a fang attached to the venom gland on the first two appendages. Spiders use these two fangs to immobilize their victims or to defend themselves.
Below these are two other appendages that are used as a mouth. They have eight legs, with four on each side The abdomen is mostly for food storage, but this component also makes the silk for webs, and the lungs are located here. Silk is developed in a special gland in the abdomen. While spiders have simple eyes, they are not typically well-formed, so they use vibrations to sense movement on the surface of their web. The tiny bristles spread all over the body surface of the spider are sensitive tactile receptors that respond to many stimuli, including pressure, vibration, and airflow. The silk can be extremely strong and is used to capture their prey, but there are also other approaches. The adhesive properties of the web work only for about two days and then the spider eats the silk and creates a new web. The size of spiders can vary a lot and while many are very small, some can be up to 9 cm in length.
The silk created by spiders is used for building webs, for trapping prey, for storing food, for escaping risk, for making egg bags, for sending and receiving vibrating signals, and for transporting silk ropes called “ballooning” as spiders spread around their young.
Many species of spiders create specific types of webs of silk to catch prey. Many big spiders may have a painful bite, but they are typically not so dangerous. Most spiders have poisonous venom, but their teeth are too weak to penetrate human skin. Only around 200 of the 34,000 species of spiders can be dangerous to humans as they have a poisonous toxin and a snap that can penetrate human skin. The most widely recognized of these are the black widow spider, the brown recluse spider, and the funnel web spider.
