Source: Science and Technology Daily WeChat public account
Qingqianlong dragon robe "Xiangyun bat" flower case
在我国传统建筑、服饰花样里，蜜蜂与猴子在一起，象征着“封侯”的美事；而蝙蝠和梅花鹿则意味着“福禄”双全。 Whether it is the prayer of "Fu Shou Shuang Quan" or "Five Blessings Linmen", bats have always been regarded as a symbol of auspiciousness and happiness.
However, bats are also among the most fascinating and incomprehensible creatures in the world. In many parts of the world, it is also considered a "ominous bird" and a "ghost in the dark", which seems to be a symbol of evil and fear. In fact, bats are actually a generic term for pterodactyls, which are not only not evil, but also part of the great benefit to humans and ecosystems.
Bats are the second largest group of mammals after rodents, with about 1390 species in existence, and are found in various ecosystems except for some islands in the polar regions and oceans. Today, even though we know the role that bats play in the biological chain and provide valuable services to humans, we still know very little about it and misunderstand it because it is mostly only nocturnal.
<h1 class= "pgc-h-arrow-right" > the only flying mammal, a relative of pterosaurs and mice? </h1>
As the only mammals that can be active in the air, bats are quite unique. But what animals were the ancestors of bats?
Some people like to associate bats with pterosaurs, including some naturalists in the early West, but pterosaurs became extinct in the last years of the Mesozoic Era, leaving not a single living offspring. So far, paleontologists have never found any bat fossils in the Mesozoic Era.
Some studies say that modern mammals, including the pterodactyl order of bats, originated in the late Cretaceous period 80 million years ago, and even if this theory is correct, it can only mean that the ancestors of bats were separated from other mammals in the age of dinosaurs, and it does not prove that it evolved into bats.
Others say that bats evolved from rats, which is also untenable. Through the mammalian phylogenetic evolution map, people can clearly see that bats and mice were separated after the extinction of dinosaurs, they are parallel evolutionary relationships, and rats cannot become bats. Although there are also about 38 teeth, it is a pterodactyl, not a rodent, which is also a long-term cognitive error.
It is a bat with an index finger, 14 cm long and a wingspan of 37 cm
The climate was very warm in the early Cenozoic, and with the advent of the "Paleocene-Eocene Extreme Heat Event" 56 million years ago, the evolution of bats ushered in new opportunities. Flying insects were particularly abundant at that time, and bats began to jump from tree to tree in order to feed on flying insects, and in order to adapt to this new way of life, the ability to fly came into being. But the immediate ancestors of bats still maintained their most primitive appearance: small, nocturnal, arboreal, and insectivory.
In 2003, in the 52.2 million-year-old Eocene strata of the Green River Formation in Wyoming, USA, researchers identified two particularly important classes of early bats, the Islamic bat and the clawed bat, both of which have exhibited key characteristics of flight, such as the fusion of the radius and ulna of the forearm and the extension of the 2nd to 5th forebel toe to support the membrane cover.
Both the islamic bat and the claw bat show some ancestral signs, such as a longer tail and more developed hind limbs, adapting to climbing in trees; today's bats have weak hind legs and can only crawl and roll like broken umbrellas blown by the wind.
In addition, the wings of the islamic bat and claw bat are shorter and narrower, flying faster than modern bats, and may alternate flight and gliding. These findings strongly prove that the ancestors of bats were arboreal, and the flight of bats originated from landing from trees.
< h1 class = "pgc-h-arrow-right" > evolved flying and extraordinary predatory energy, accounting for 1/4 of the total number of mammals</h1>
The British modern naturalist John Arthur Thomson wrote in The History of Animal Life: "When insectivores that fly down from high to eat from high places evolve into bats, the gods of nature must be laughing, because they did originate in this way." "As mammals, they hang themselves on their toes and wrap themselves between their wings, which is truly a miracle in the world. But they are covered with dark fur and feed only 1 cub at a time – at most two – and are indeed mammals.
To facilitate flight, bat forelimbs evolved into wings. Between its "shoulders" and its thumb, there is a sensitive membrane that connects the slender fingers and extends from the little finger to the heel, and then from the heel along the side of the body to the armpit, which is the unique wing membrane of bats. They fly with open arms and fingers and outstretched wings.
Because the bat's skeleton is very flexible, it feels like its fingers grow directly from the wrist; but its hind limbs are generally weak and weak, and its knees are bent backwards, so the function of walking on the ground has been very degraded. As if to say, "If you have bird-like wings, you don't have to walk on dangerous and rough ground." ”
They use long claws on their toes and thumbs to cling to rough surfaces of objects, and some have evolved suction cups, such as the suction cup wing bat distributed in Central and South America. When resting, Brother Bat hangs his feet upside down on trees, cave walls, or beamed roofs of old buildings, with his head hanging downwards and folding his wings.
You know, the skeleton structure of the Archaeopteryx that lived 32 million years ago was almost exactly the same as that of today's small insectivorous bats, without much change. In this hundred million years, bats have mainly learned two things, one is to fly, and the other is echolocation. These are two fairly successful evolutions that greatly enhance the foraging and avoidance efficiency of bats.
Of course, because the wings of bats appear more than 100 million years later than birds, the ecological niches of larger flying animals are basically occupied by birds, which also limits the development of bats, and no other new skills have evolved in more than 30 million years.
Today, there are 1390 species of bats, a quarter of the total number of mammals, the second largest family of mammals after mice. But the conservatism of its evolution means that the early evolution is successful, and it can adapt well to the environment without making too many changes.
<h1 class= "pgc-h-arrow-right" > has super flying skills and echo positioning system</h1>
Among mammals, there is a species of shrew monkey under the order Offinchron, which seems to be able to "fly", but it is not yet up to the level of bat kindergarten. Shrew monkeys have wing membranes with their necks extending from their tails, but they can only glide down short distances from high places, and cannot fly low to high towards bats or birds.
But bats are different, they can fly from flat ground to the air, and their flying skills are still very strong. When flying through houses, they are surprisingly sensitive to avoiding beams, columns, and other objects.
Even in the open, their flying skills are on par with birds, dexterous whirling, rapid retreat, somersaurus is their housekeeping skill, so they can accurately capture moths, mosquitoes and flying scarab beetles, and all of this comes quietly.
In early studies, due to the times and technology, people could not understand why bats with poor vision could fly dexterously at night and catch prey, but there was speculation about their prominent round ears and developed hearing.
In fact, bats make a sound while flying. This sound is called ultrasonic, and the human ear cannot hear it, but the bat's ear can not only hear, but also accurately accept the circuit signal and locate its position and flight direction.
Experiments have proved that most bats use ultrasonic pulses from the throat to locate, and there are also some large fruit-eating bats such as brown fruit bats, whose echolocation ability is more special, using the sound of the tongue as the basis for sound localization. The ability to echolocate is important for bats to survive and reproduce, allowing them to occupy ecological niches that birds cannot use at night or in more dim environments.
Most bats call at frequencies between 20-60 kHz. But some slower bats can respond to high-frequency sound waves, which are also "weapons" for their survival.
The short-eared trilobite-nosed bat can make a very high frequency of 212 kHz, the highest of all bats, while some bats of the canine-kissed bat family, such as the small spotted bat, can echolocate as low as 11 kHz. The significant benefit of using particularly high or low frequency calls is that such sound waves are difficult to perceive by prey, so they can catch more insects.
Of course, bats evolved echo positioning skills more than 30 million years ago, but prey is not idle. Predators like the chrysanthemum bat we are familiar with today have been playing a biological "cat-and-mouse game" with their prey.
Bats have echo localization systems, while some moths, which are generally harmful to crops, evolve eardrums to discover bat calls; others make their own sounds to disrupt the bat's sonar system.
The ultrasound pushes forward like a wave, reflects back when it encounters an obstacle, and reaches the bat's ear, and the bat immediately changes the direction of flight. Bat Brother is proud that its live radar is particularly resistant to jamming, even if the interference noise is twice as strong as the ultrasonic waves it emits, it can still work effectively, guiding itself to accurately pollinate plants and prey on pests in the dark.
<h1 class="pgc-h-arrow-right" > bats "vampires"? In fact, the world really can't do without it</h1>
In Western culture, bats are even stigmatized as "vampires", but in reality, out of 1390 species of bats, only 3 are blood-eating, and only one of them is aimed at mammals.
All blood-eating bats are also limited to Latin America and are not available elsewhere. And it should be noted that they do not suck blood, but lick and eat blood like kittens, and their saliva contains anticoagulants to prevent blood from clotting, so that they can eat smoothly. And this stuff has now been developed into drugs to prevent strokes in humans.
The vast majority of bat species feed on insects, including extremely harmful agricultural pests. Others feed on fruits, flowers, nectar, etc., and indirectly pollinate the plants to ensure that the plants grow from generation to generation.
When people think of pollination of flowers, they usually only think of bees and birds, etc., and most people don't know that bats play an important role in pollination of tropical plants. About 528 species of tropical plants in 67 families are pollinated by bats each year, and more than 300 of them are fruit plants.
Various bats that feed on nectar (Source: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences)
Durian has a strong smell and is known as "the world's stinky fruit", but it is an important cash crop in Southeast Asia. The latest study from 21 November 2019 confirms that three species of bats, the large long-tongued fruit bat, the central fox bat and the Cybelisian-toothed fox bat, pollinate durian flowers all year round.
The rare shovel-toothed bat is found only in Peru and is the only bat pollinator of several columnar cacti in Peru. The baobab tree of the East African savannah, which is vital to the survival of animals, is known as the "African Tree of Life", and it relies almost entirely on bat pollination. Without bats, the Tree of Life could have gone extinct.
Most of the visiting bats are mainly found in Southeast Asia and the Pacific Islands. Without bat patronage, ecosystems in these places could gradually collapse because plants cannot grow properly to provide food and shelter for animals.
Bats don't end there. Many bats are also migratory animals, and they bear similarities to migratory birds and can fly thousands of kilometers. Bats eat plant fruits and spread seeds everywhere, which ensures regional species diversity.
Studies have confirmed that they spread far more seeds than birds, and many bats spread pioneer plant seeds, the first seeds to grow in harsh environments.
As these pioneer plants grow, creating a small environment, other plants with higher environmental requirements can grow in the second stage. Tequila is a very popular liquor, it comes from the tequila plant, and bats are responsible for the spread of most seeds. Figs, cashews, etc. also rely on bats to spread seeds.
Therefore, some scientists have seriously pointed out that bats help maintain the ecological balance of forests and can provide people with delicious durian fruits. It is hoped that the inhabitants of Sulawesi will recognize the importance of bats and avoid hunting and destroying their habitats.
<h1 class="pgc-h-arrow-right" > a serious warning! One of the most painful costs of virus transmission or ecological damage</h1>
In the process of preventing and treating the new crown pneumonia epidemic in 2020, the behavior of some people eating bats in Southeast Asia has been spurned and angrily rebuked by the world.
Perhaps early humans were forced by the pressure of survival, and the vice of eating bats was no longer a day or two. Wallace, a contemporary of Darwin, once recorded the consumption of the Malay foxbat: "This creature is extremely ugly, indeed delicious, and has become a target for people to hunt." At the beginning of each year, they forage for fruit in groups and gather on small islands in the bay during the day, hanging tens of thousands on trees, especially dead trees. "Cooking requires careful handling, because the fur has the stench of a fox, and it usually adds a lot of spices and condiments, which is simply a good taste, and it tastes a bit like hare meat." How to achieve the transformation between the stench of bats and the superior delicacy is questionable, but 32 million years ago, bats evolved to make other species unpleasant, smell, and people have to provoke it, which really makes more people speechless.
** What can be perceived is the strange appearance and smell of bats, and what the naked eye cannot perceive is that it is also a natural host for dozens of viruses, and people should stay away from them rather than mutilate them.
On April 10, 2020, researchers from the Smithsonian Institution's Global Health Program discovered six new coronaviruses in bats in Myanmar that had not been previously found elsewhere. They studied the potential for the spread of these viruses across species to assess their threat to human health. The researchers said the newly discovered coronaviruses were not closely linked to SARS, Middle East respiratory syndrome and the novel coronavirus. **
In 2005, Daszak et al. also found viral DNA that is very similar to the SARS virus in three horseshoe bats. However, although the sequence of these viral genomes has 88%-92% identity with the sequence of the SARS coronavirus, they show significant differences in regions encoding so-called spike proteins, meaning that bat viruses will not be able to infect human cells.
And, because some palm beaver subfamily have been found to carry almost the same virus as the human SARS virus, most researchers believe that SARS spreads from bats to mosquitoes, which are transmitted from mosquitoes to intermediate hosts similar to civets, and then humans.
On March 19, 2020, the results of a study by Zhang Zhigang's team at Yunnan University on the possibility that Malay pangolins may be potential natural reservoirs for the new coronavirus, officially published in the Cell sub-journal Contemporary Biology, do not seem to have attracted enough attention.
Previously, researcher Shi Zhengli of the Wuhan Institute of Virology reported that the genome of the bat coronavirus RaTG13 and the new crown virus was more than 96%, proving that the Chinese chrysanthemum bat is a potential natural source of the new crown virus.
At the same time, based on the situation in Wuhan at that time, some people in the academic community speculated that pangolins may be the "intermediate host" of the new crown virus. But zhang Zhigang's team's study proves that pangolins are not intermediate hosts for the new coronavirus, but, like the mid-chrysanthemum bat, a potential natural host for the new coronavirus. In other words, until the final answer is revealed, the bat should not be alone to bear the suspicion.
In fact, 75% of the newly emerging human infectious diseases in modern times originate in animals, including bats. With the rapid expansion of the population, species that were originally in natural areas began to adapt to the human living environment, and contact with humans increased.
Studies have shown that more than 60% of emerging infectious diseases are zoonotic. Bats, like most wild animals, are avoiding contact with humans. Human beings should conform to nature and do everything possible to protect the natural environment, rather than wantonly plundering and "breaking the magic bottle", of course, including not preying on wild animals such as bats, in order to avoid nature's punishment.
Although there are as many as 1390 species of bats, the number of bats is not large in terms of overall biomass compared with other animals, and some species are even solitary and endangered. As human hands and feet stretched longer and longer, bat habitats and original ecosystems were destroyed, and the gathering of tens of thousands of bats described by Wallace more than a hundred years ago has become increasingly rare on the planet.
In human production activities, the poisons used to destroy insects, as well as wood protection agents, will also cause bats to die directly or indirectly; at the same time, many misconceptions are still driving humans to hunt them in large numbers. Some species of hollow trees have been cut down and the ruins have been demolished or rebuilt so seamlessly that they cannot survive. Like other animals, many bats are becoming less and less common in nature, which is a long sigh.
It is a new era in which both the East and the West can no longer decide the fate of a species with misconceptions, and the hunting of any natural species, including bats, can bring the most dangerous ecological revenge.
Now, what we have to do is to create a world where bats and humans coexist, and at that time, nature will also give back to us Chinese the "five blessings" that have been hoped for since ancient and modern times, which are true and true.