Most spiders have eight eyes of different sizes. Although most spiders have many eyes, the spider is a poor myopia. What it sees is always vague, and it basically relies on feelings to feed and survive.
Spiders look like insects, but spiders are not insects, so spiders' eyes don't have compound eyes like insects. Spiders have eight eyes. It is said that these eight eyes have a clear division of labor, some are responsible for seeing things during the day and some are responsible for seeing things at night. Isn't it amazing?
Spider shape:
Body length varies from 0.5 mm to 9 cm. The body is divided into chest and abdomen. There is a carapace on the head, chest and back, and there are usually 8 single pieces at the front end of the carapace, arranged in 2-4 rows. There is a big chest plate on the ventral surface and a lower lip in the middle of the chest plate. Abdominal knotless abdominal stalk evolved from abdominal node 1
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. There are many spinning tubes on the spinning machine, which are connected with various silk glands and spin silk from the spinning tubes. Sensory organs include eyes, various sensory hairs, suture sensory organs and tarsal organs.
Spiders prey:
Spiders mainly prey on small insects. Stealing spiders near the water can prey on small fish and shrimp, bird-catching spiders can catch birds, and a 7.5-cm-long spider in South America can even prey on small rattlesnakes. Web spiders prey on their webs.
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 several days and peeled 1-2 times in the bag. Young spiders shed their skin 4- 15 times before maturity.
Spider silk plays an important role in spider's life, and netting is an 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.