There are always countless legends of life in nature, such as the Pompeii worm that "bathes leisurely" in the heat of nearly 100 ° C, and the swift that flies nearly 300 million kilometers a year. These creatures have proved with their own "deeds" that "there are thousands of worlds, and there are no wonders."
swift
And the creature we want to talk about today, also uses its own body size flight distance, proving what is legendary, it is a thin-winged dragonfly. Although it weighs less than 1 gram, it can fly 6400 kilometers and cross the Indian Ocean, breaking the life limit.
Little dragonfly, across the ocean
Dragonflies should be a kind of insect that we often see in life, but there are obvious differences in its name everywhere, such as electric lights, ding-ding cats and other dragonflies. Dragonflies are not only very good-looking, but also a beneficial insect that can help people prey on flies, mosquitoes and other organisms.
Dragonflies are beneficial insects
Previously, it had been believed that only birds could cross the ocean, but more and more discoveries proved that nature's creativity was far beyond human imagination. In 2016, an American biologist made a surprising discovery while studying the genetic makeup of insect samples from North and South America and Asia.
Originally, there is a thin-winged dragonfly, which is distributed in the United States, Canada, Japan, South Korea, India and other places, and its genetic map comparison shows that the thin-winged dragonfly in the United States and the thin-winged dragonfly in India are genetically similar, which proves that dragonflies in the two places may have genetic exchange.
Thin-winged dragonfly
Therefore, scientists immediately tracked parts of the thin-winged dragonflies in the West Asia region to try to figure out their flight trajectories. After the dragonflies living in West Asia took off from the local area, they finally reached Africa. This proves that they flew about 6400 kilometers during this period, crossing the Indian Ocean.
Cross the Indian Ocean
Of course, crossing the Indian Ocean is estimated to be only a "small test knife". Because we said earlier, the thin-winged dragonfly in the United States and the thin-winged dragonfly gene in India show a super high similarity, which means that the thin-winged dragonfly may have also crossed the Pacific Ocean and achieved ultra-long-distance flight.
The point is that the thin-winged dragonfly is a very small one of the dragonflies, weighing only about 1 gram. It is really puzzling to be able to use such a small body to achieve the feat of crossing the ocean. So scientists are trying to do research and find out why this guy is so capable of flying.
Thin-winged dragonflies are small in size
They believe that thin-winged dragonflies can fly so far for several reasons: First, their large wing surface area means that they can fly at an altitude of more than 1,000 kilometers.
At this point, the thin-winged dragonfly does not need to fly by individual effort alone, but can "hitch a ride" and use the prevailing wind to move forward.
Secondly, due to the small size, the microorganisms in the atmosphere along the way should be enough for them to survive, so long-distance flights will not die due to inability to forage. You can keep flying like this, and eventually reach the pond you want to go to, and mate and spawn.
Arrive at the pond to mate and lay eggs
It should be noted that the flight of thin-winged dragonflies is essentially an adventure to challenge the limits, and in the process, there will certainly be a large number of dragonflies dying. But due to the large number of breeds, there were survivors who managed to reach their destination.
Thin-winged dragonfly
It is worth mentioning that in addition to the thin-winged dragonfly in terms of long-distance flight, people are eye-opening. Dragonflies themselves have strong flight ability and have always been the object of great concern of scientists.
Dragonfly's ability to fly
I don't know if you have carefully observed the flight of dragonflies, often feel that one second it is still vibrating its wings at high speed to fly, and the next second it can "shallow on the brakes" and hover steadily in the air. Then I was stunned for a few seconds, and when I needed to fly, I could quickly change to a flying state.
Data show that in the insect kingdom, dragonflies have the fewest number of wings flapping when flying, 30 to 50 times per second, and the flight speed is the fastest. It can fly long distances, change direction and accelerate at will, and sprint flight speeds can reach up to 40 m/s.
Dragonflies vibrate their wings
Because of these characteristics, the dragonfly has always been known as a fighter in the winged insect world. Because of its flight, it is mainly through the vibration of the membrane wings to generate local unstable air flow, and then use the vortex rising generated by this air flow to fly.
The dragonfly's super flight ability is essentially the most related to its wings. Because its flight behavior is actually not complicated, it is flapping by its wings, and occasionally it can stretch its wings to fly forward. Don't underestimate the wings of the dragonfly, which, although it looks very thin, is actually quite flexible and has a very considerable intensity.
Wings as thin as cicada wings
It is precisely because of this that the wings can help the dragonfly achieve a variety of movements such as circling and sliding, and even allow it to quickly change direction during flight. For example, when a dragonfly hovers over, it obtains lift by changing the phase difference between the forewings, and when the hindwings are a quarter of a cycle ahead of the flapping frequency of the forewings, the lift reaches its maximum.
Composition of the wings
In addition, dragonfly wings have the ability to clean themselves. Because dragonflies prefer to live in warm, humid places, their wings must be able to withstand the invasion of rain and fog. If it is said that once it is wet, it needs to be dried or recovered for a long time, then it is very unfavorable for it.
The wings are rainproof
Therefore, in the long-term evolution of dragonflies' wings, they have long formed anti-adhesion and difficult to wet characteristics, and the composition of the surface of their wings can not only allow water to take away pollutants, but also maintain dryness at all times.
You know, in the thin-winged dragonfly we introduced above, it weighs less than 1 gram, which is its advantage in flight, because the weight is small and the resistance is small. However, if the wings are wet and add a lot of unnecessary weight, then the speed of their flight and the distance they fly will be affected.
The outermost layer of the epidermis of the dragonfly fin membrane is distributed with a thin columnar waxy material layer with a thickness of about 0.6 μm, which is about one-third the thickness of the epidermis of the fin membrane, which can effectively waterproof.
Waxy surface
Of course, according to the research of scientists, dragonfly wings also have anti-fatigue characteristics, vibration and noise reduction characteristics, etc., which are its advantages in long evolution, and it also uses these advantages to fly over ultra-long distances.
If we can carry out biomimetic research based on these characteristics, make a bionic flapping wing flying machine, and create a flying machine similar to the dragonfly wing and flight mechanism, then it will bring great progress to biotechnology.
Get inspired by the flight of dragonflies
In addition to the wings and flight characteristics that can provide enlightenment for humans, the existence of dragonflies has many values, which can be divided into four aspects, namely intrinsic value, economic value, ecological value and social value.
The value of dragonflies
First of all, let's talk about the intrinsic value, which is not evaluated by the will of man, but mainly by the value created by the continuation of the species itself. According to the available records, there are about 6258 species in 686 genera in 39 families and 686 genera worldwide. Dragonflies were born early on and have been at the top of the food chain.
There are many types of dragonflies
For example, the giant dragonfly in the Permian period, its wingspan can reach more than 70 centimeters, although the shape is similar to the current dragonfly, but this huge volume is very frightening.
Giant dragonfly
The second is the economic value of dragonflies, and some areas have the custom of eating insects, such as Brazil, Mexico, Congo and other countries. At present, there are about 58 species of dragonflies known to be edible, including yellow dragonflies, red dragonflies, longhorn sub-spring dragonflies and so on. However, people generally only eat the baby worms of dragonflies, because their bodies are rich in nutrients.
Fried dragonflies
The economic value of dragonflies is also reflected in the medicinal aspects, in the "Famous Doctors" and "Compendium of Materia Medica" have recorded the method of dragonflies into medicine, in the eyes of Chinese medicine, this is a rare health medicine.
The third is the ecological value of dragonflies, which we mentioned earlier, and dragonflies are essentially beneficial insects. And it often has special requirements for the habitat environment, which has led to the fact that it is now often regarded as an indicator organism to monitor whether the ecological environment is qualified.
Test the ecology with dragonflies
Finally, the social value of dragonflies, in the process of getting along with humans, dragonflies have always been loved by everyone, leaving a strong mark in the field of literature and art. For example, in the poetry of the Song Dynasty, it is very fond of describing dragonflies, and also gives it the image of "the flowers have feelings, and the dragonflies have no intentions".
Dragonflies and poetry
In this way, the dragonfly not only allows us to see the limits of life, but also allows us to see its unique beauty. However, everyone still has to love the dragonfly, don't catch it when you see it, let it fly freely in nature!