Do dragonflies also want to hibernate How do dragonflies survive the winter

<> "1. How dragonflies survive the winter.

Dragonflies generally overwinter as larvae and open their first eyes. Before the arrival of winter, they will eat a lot of food to store their energy for winter consumption. Due to the low consumption in the body, there is no risk of frostbite.

2. Are dragonflies beneficial or pests?

Dragonflies are beneficial or harmful to see in stages, larval dragonflies, that is, water flies, are small fish, tadpoles for life, very fierce, is the pest of farmed fish, especially the cultivation of fry and tropical fish breeding, must be cleared.

After maturing and feathering, it becomes a beautiful dragonfly is a big beneficial insect, with flies, mosquitoes, moths and other pests as the bright food, they are almost born to catch pests, which is of great help to human life, not only to the health of people, but also to the abundant yield of farmland crops, also plays a great role.

Dragonflies overwinter as larvae, and the adults have already left offspring.

"Water scorpion" is the larvae of dragonflies, dragonflies lay their eggs in the water in autumn, and after a winter and spring development, they will grow into three or four centimeter long larvae, and fly out of the water at the turn of spring and summer.

Hibernation and resuscitation of insects.

Insects are ectotherms, and their body temperature and activity state change with the outside air temperature. The season of spring is the time for them to wake up and move; The scorching summer is a period when they have a large number of children; The crisp autumn season is the day when they are busy preparing for winter; In the winter when the water turns into ice, the insects' respiratory metabolism, exercise ability, feeding ability and reproductive ability are greatly affected, so they use various skills to survive the cold and windy winter.

The state of various insects that overwinter is not the same.

Locusts, rice planthoppers, etc., overwinter with eggs. Before laying overwintering eggs, locusts first find a relatively hard place such as a ridge or roadside, and then use the oviposition at the end of their abdomen to make a small hole in the ground, and then lay the eggs in the hole. At the same time, the locusts also discharge the glue and wrap the eggs tightly to facilitate overwintering.

Corn borer, longhorn beetle, etc. overwinter with larvae. Corn borer larvae burrow into corn, sorghum, millet and other stalks for overwintering. The larvae of the longhorn beetle, which digs "tunnels" in the trunk, spend the winter in the trunk.

There are many insects that overwinter as adults, mainly small species. For example, some aphids often spend the winter on the young shoots of Asteraceae plants such as spiny cabbage and dandelion on the sunny leeward slope of the mound.

Insects such as mosquitoes and flies survive the winter in a multi-insect state. Take mosquitoes as an example, some mosquitoes store rich fat in their bodies, and quietly lie down in the dark and warm fields of vegetable cellars, indoor corners, grass piles, and tree holes for the winter; There are also those who spend the winter with their wives and eggs.

All insects that overwinter with adults and larvae, as soon as winter comes, they are insatiable to eat, always eat their stomachs to the full, and try their best to store more nutrients in their bodies for consumption in the long winter. From the point of view of the insect itself, a series of physiological changes will also occur when winter comes. For example, the accumulation of nutrients such as fat and sugars in the body is significantly increased, the water content is greatly reduced, the breathing is slow, and the metabolism is reduced.

These physiological changes help to reduce the body's exertion and prevent them from freezing into ice at low temperatures, so they will not freeze to death even after four or five months of winter.

Adults usually freeze to death, after a heavy frost.

Dragonflies do not have eyelids, they sleep with their eyes open.

1. Basic introduction of dragonflies:

Dragonfly, invertebrate, insecta, dragonfly, a common name for insects of the suborder Paraptera. Generally large, the wings are long and narrow, membranous, and the reticulate wing veins are extremely clear. Extremely sensitive vision, 3 in one eye; antennae 1 pair, thin and short; Chewing mouthparts.

Dragonflies are the insects with the most eyes in the world. Dragonflies have large, bulging eyes that occupy most of their heads, and each eye is composed of countless "small eyes" connected to photoreceptor cells and nerves, which can distinguish the shape and size of objects, they have excellent vision, and can look up, down, forward, and backward without having to turn their heads.

Second, the appearance characteristics of dragonflies:

Dragonflies are the insects with the most eyes in the world. Dragonflies have large, bulging eyes that occupy most of their heads, and each eye is composed of countless "small eyes" connected to photoreceptor cells and nerves, which can distinguish the shape and size of objects, they have excellent vision, and can look up, down, forward, and backward without having to turn their heads. In addition, their compound eyes can measure speed.

When an object moves in front of the compound eye, each "small eye" reacts in turn, and the speed of the target object can be determined after processing. This makes them masters of insect catchers in the insect world.

All animals need to sleep, and if they don't get a break for too long, they will make up for the delay just like humans. Animals can also die if they don't sleep for a long time.

Scientists have long noticed that the larger the animal, the less it sleeps. Horses, giraffes, and cows, which spend a lot of time grazing. Horses usually sleep for 3 hours, giraffes only need to sleep 2 hours a day, elephants sleep only 4 to 5 hours, and they are also animals that sleep less.

Although the lion is not small, it sleeps up to 18 hours a day, and it is an extremely obvious sleepy animal.

Nils Rattanberg, an American ornithologist working at the Max Planck Institute for Ornithology in Mapu, is interested in the sleep of migratory birds. A North American songbird migrates 4,500 kilometers from its summer habitat of Alaska to California every year. Observations of these animals in their cages have shown that they are almost always awake when they are subjected to "migration disturbances".

First of all, where it thinks it is safe, there is no fixed place! For example, under the leaves in the grass, on the stones, and even on the road! In short, there are no fixed rules And because dragonflies don't have eyelids, it's impossible to close their eyes, they sleep with their eyes open.

And you can also see things from the outside world.

Secondly, dragonflies can be divided into the suborder Paraptera of dragonflies and the homoptera of damselflies (bundle wings), there are only three kinds of dragonflies in the mesoptera order are in Japan, India, China, this suborder is known as a living fossil, the oldest in China. It is also a very primitive insect in the winged subclass. The larvae, called larvae, are completely aquatic and have a completely different morphology and habits from the adults.

The morphology of the various larvae varies greatly.

Where it deems safe, there is no fixed place.

For example, under the leaves in the grass, on the stones, and even on the road! In short, there are no fixed rules.

And because dragonflies don't have eyelids, it is impossible to close their eyes, and they sleep with their eyes open. And you can also see things from the outside world.

In the evening, you can take a closer look at the grass along the secluded paths and in the flower beds.