A cicada's life goes through three different stages: egg, larva and adult.

The larvae of cicadas live in the soil, sucking the sap from the roots of plants, weakening the tree vigor, causing the branches to die and affecting the growth of trees. The larvae of grasshoppers live in the soil all their lives. When you are about to emerge, drill out the surface at dusk and at night, climb to the tree, then grasp the bark and molt and emerge. At the end of June, larvae began to emerge into adults, and the longest life span was about 6 ~ 7 days.

in late July, female adults began to lay eggs, and the peak of laying eggs was in early and middle August, and most eggs were laid on branches with a thickness of 4 ~ 5 mm. When female adults lay eggs, they first pierce the bark with an ovipositor, insert the ovipositor into the branches to form claw-like egg holes, and then lay eggs in the xylem. Each spawning hole has 6 ~ 8 eggs. There are more than 9 cicada eggs on a branch.

In areas where this insect is seriously occurring, it is common that the trunk is full of dead branches at the end of autumn. The eggs laid will hatch in the middle of June of the following year. After the larvae hatch, they fall to the ground from the branches and then drill into the soil. Larvae live in the soil for several years, and molt 5 times. Whenever spring is warm, the larvae move upward, sucking the juice of plant roots, and when autumn comes and winter comes, they go deep into the soil to avoid the cold.

The body of young larvae is mostly white or yellow, which is very soft and the forehead is obviously enlarged. The body of the aged larva is hard and yellow-brown, with well-developed wing buds. From the top of the head to the center of the back of the chest, there is a molting line, which is the cracking line when the adult emerges. When the cicada's upper body is free, it hangs upside down to spread its wings. At this stage, cicada's wings are very soft.

they are unfolded through the body fluid tube. The body fluid tube spreads its wings by the pressure of liquid. When the liquid is pumped back into the cicada, the spread wings have become hard. If a cicada is disturbed in the process of spreading its wings, it will be disabled for life and may not be able to fly at all.

Extended information:

After mating between male and female cicadas, the male cicada quickly aged and fell to the ground to die, leaving the female cicada behind. The female cicada uses a pointed ovipositor to pierce a circle of small holes in the twig, and lays eggs in the wood of the tree. At the lower end of the twig, she also pierces a circle of phloem with a mouthpiece, so that the branch is cut off from the supply of water and nutrients, and the twig gradually dies. In this way, branches with eggs are easily blown to the ground by the wind.

so that the hatched cicadas (called larvae) can get into the soil. The eggs laid by cicadas hatch into young cicadas in half a month. The life span of young cicadas is particularly long, the shortest one has to live underground for 2-3 years, usually 4-5 years, and the longest one is 17 years. Young cicadas live underground for a long time, with warm winter and cool summer conditions, and few natural enemies to threaten them, but they are also comfortable.

after molting for 4-5 times, they have to drill out of the ground, climb onto the branches and molt in turn (called cicada molting) to become adults. What puzzles entomologists is that cicadas can accurately determine the time, complete the transition growth from larvae to adults in "hell" and climb out of the ground at the right time.

this is an incredible miracle. Especially in the 17-year cicada, this kind of cicada is neither too much nor too little, and it is only after 17 years of "hell" life that the light of day is seen. It will take another 17 years to see its children. Therefore, entomologists are always waiting for the "17-year cicada" like astronomers waiting for the solar eclipse and Halley's comet.

There is a story in Zhuangzi:

Once Confucius took his disciples to the State of Chu. On the way, he passed a forest, where an old hunchbacked man was sticking cicadas with a bamboo pole. It is very easy for him to stick to cicadas, just like picking them up on the ground. Confucius stepped forward and asked, "What a coincidence! Is there any doorway? " The old man replied, "I really have my own way. I have been practicing for five or six months."

"I put two balls on the top of the pole and they won't fall, so it's rare to miss when I practice;" Put three balls together without falling, so that the situation of missing will not exceed once in ten times; Putting five balls together without falling will be as easy as picking up cicadas on the ground. "

"I stand still, just like a stake plunged into the ground, and the arm holding the pole is like a dead branch. Although the world is vast and there are many kinds of things, I concentrate on the wings of cicadas, never think about it, look around, and never change my attention to cicadas because of all kinds of things. Why can't I succeed? "

Finally, Confucius turned to his disciples and said, "As long as you concentrate on it, you can practice your skills to perfection. This is what the hunchback old man said." Old man's sticking to cicada is a word popularized by later generations. The original sentence should be: slough and inherit.

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