What exactly does dragonfly mean?

In fact, skimming refers to the metaphor of superficial kung fu.

Expanding knowledge-dragonfly

Dragonfly is an insect of Odonata, Odonata and Matoumen. Dragonflies have developed wings, and the base of the rear wing is slightly larger than the front wing. When resting, spread your wings and lie flat on both sides; Flexible head and short antennae; The compound eye is developed, with three single eyes, and the chewing mouth is powerful; The abdomen is slender, the feet are thin and weak, and there are hooks and thorns on them; Larvae is short and thick, with rectal gills and no tail gills.

Dragonfly is a typical incomplete metamorphosis insect, and it is also the insect with the most eyes. "Compendium of Materia Medica" contains: "Dragonflies end up green; The rainbow is lonely, or the tail of the cloud is like a nail, or the tail of the cloud is so high and straight. So, very embarrassed, very embarrassed. "

Morphogenesis

The shape and pulse sequence of the front and rear wings are different; Wing base is not stipitate, not obviously long and narrow; The middle cavity is divided into triangular cavity and upper triangular cavity by oblique veins, which usually have different shapes on the front and rear wings; Two compound eyes touch or are separated by a thin seam; Male 1 anal appendage; At rest, the four wings extend horizontally to both sides.

wing

The research on dragonfly wings mainly focuses on mechanical principles and bionics. Dragonfly wings have two special structures: wing knots and wing moles, which make it an excellent flier in nature. In the study of mechanics, it is found that the dragonfly's wings will be affected by horizontal force, vertical force, moment, bending and movement when flapping and turning in the air, and it is found that the slow flight of dragonfly is very similar to that of an airplane.

The research methods of flight mechanics of dragonfly wings are also constantly improving, from tying with ropes to shooting with high-speed cameras and then observing in wind tunnels. More and more advanced methods make the study of dragonfly flight mechanics deeper.

Living habits

Dragonflies like wet environment, so they usually fly in ponds or rivers, and their larvae (larvae) also need to develop in water.

Odonata is a semi-metamorphosed insect, which has only three stages in its life: egg, larva and adult. Adults often lay eggs in water by skimming. Larvae, also known as hydra, preys on other aquatic organisms in the water, climbs out of the water before emergence, mates and lays eggs, and completes its life history.