bat
A general term for Chiroptera, especially Batsuborder.
Bats are the only mammals that have evolved real flying ability, with more than 900 species. Most of them also have keen auditory localization (or echolocation) systems. Most bats feed on insects. Because bats prey on a large number of insects, they play an important role in the balance of insect reproduction and may even help control pests. Some bats also eat fruit, pollen and nectar; Vampire bats in tropical America feed on the blood of mammals and large birds. These bats sometimes spread rabies. Bats are distributed all over the world. In the tropics, bats are extremely abundant, and they will be integrated into large groups in people's houses and public buildings. Bats vary greatly in size. The largest blood-sucking flying fox has a wingspan of 1.5m, while Kitty's pig-nosed bat has a wingspan of only 15cm. Bats vary greatly in color, fur texture and facial appearance. The wings of bats evolved from forelimbs in the process of evolution. Each finger of the forelimb is extremely elongated except the thumb, and there is a flying membrane connecting the forearm and the upper arm down to the side of the body until the ankle of the lower limb. There are claws at the end of the thumb. Most bats also have two membranes between their legs, consisting of dark and bare skin. Bats have noses like rodents or foxes. The outer ear protrudes forward, usually very large and elastic. Many bats also have nasal lobes, which are composed of skin and connective tissue and flap around or above their nostrils. It is believed that the alar affects vocalization and echolocation. Bats have short necks; Broad chest and shoulders, developed chest muscles; And the hips and legs are slender. Except for the wing membrane, bats have hair all over their bodies, and their backs are gray, brown, brown or black with different shades, and their bellies are lighter in color. Bats living in open areas often have spots or mottled patches on their fur, and their colors are also different. Bats have different food habits, or prey, or help pollinate and spread fruits, thus affecting the natural order. Vampire bats are a serious problem for human beings. The excrement of insect-eating bats is used as fertilizer in agriculture. The sexual cycle of the whole bat population is synchronous, so most mating activities take place within a few weeks. The gestation period is from June to July. Many kinds of female animals will move to a special habitat after pregnancy. Bats usually give birth to 1 to 4 cubs per litter. Babies are born hairless or hairless and often cannot see or hear for a period of time. Babies are cared for by their parents for 5 weeks to 5 months, depending on different species. Almost all bats rest during the day and go out for food at night. This habit makes it easy for them to attack sleeping prey without being hurt by other animals or high temperature sunlight. Bats usually like to live in isolated places, such as caves, cracks, holes or buildings, and some live in trees and rocks. They always rest backwards. They usually gather in groups, ranging from dozens to hundreds of thousands. Bats with echolocation ability can produce short and high-frequency sound pulses, which will be reflected when they meet nearby objects. Bats can determine the location and size of prey and obstacles when they hear the reflected echoes. This skill requires a close combination of highly sensitive ears and vocal centers with auditory pathways. Individual bats can also communicate with each other in the form of sound pulses. A few bats rely on smell and vision to find food.
People often use the word "birds and beasts" to describe birds and mammals, but this statement is sometimes not necessarily correct, because some birds can't fly, such as ostriches, emus, kiwis and penguins. There are also some mammals that can't walk, such as whales living in the ocean. Bats can't walk on the ground like ordinary terrestrial mammals, but they can fly in the air like birds.
Bats are the only animals that can really fly. Although they don't have the feathers and wings like birds, and their flying ability is much worse than that of birds, their forelimbs are very developed, and their upper arms, forearms, metacarpals and phalanges are particularly long. From the end of phalanges to the humerus, sides, hind legs and tail, a thin and hairy soft and tough skin membrane is supported, forming a unique flying organ of bats-pterodactyl. There are also records about bats in ancient China, saying that they also lived in stalactite caves called fairy rats. Bats there can live forever because they can drink water from caves. After thousands of years, their body color has also changed greatly, from the initial dark color to white. I think that's why they are called fairy rats.
Bats have well-developed pectoral muscles, keel-like processes in sternum and well-developed clavicle, all of which are related to their special sports methods. It can fly well, but it needs to glide when it takes off, and it is difficult to fly again once it lands. When flying, the hind legs extend backwards to balance.
Bats generally have the habit of hibernating. During hibernation, their metabolic ability is reduced, their breathing and heartbeat are only a few times per minute, their blood flow is slowed down, and their body temperature is reduced to be consistent with the ambient temperature. However, their hibernation is not deep, and they sometimes excrete and eat during hibernation, and they can return to normal immediately after waking up. Their fertility is not high, and there is a phenomenon of "delayed fertilization", that is, fertilization does not occur during mating before hibernation, and sperm spend the winter in the female reproductive tract. After waking up in the next spring, the mating females begin to ovulate and fertilize, and then get pregnant and give birth.
Bat is an ancient and specialized branch of mammals, named after its forelimbs have special wings. It is distributed all over the world except the North and South Poles and some ocean islands, with the most species and quantities in tropical and subtropical regions. Because of their ugly appearance and nocturnal habits, they always make people feel terrible. The original meaning of their names in foreign languages is frivolous mice. But in China, because the word "bat" is homophonic with the word "fu", it can still be loved by people, and its image is painted on New Year pictures.
There are more than 900 species of bats in the world, and there are about 8/kloc-0 species in China, which is the second largest mammal group after rodents. It can be roughly divided into two categories: big bats and small bats. Bats are distributed in tropical and subtropical regions of the Old Hemisphere. They are large in size and primitive in body structure, including Muscidae, 1. Small bats are distributed in tropical and temperate regions of the Old Hemisphere and the Western Hemisphere. They are small in size and have more specialized body structures, including more than ten families, such as Batidae, hipposideridae, Batidae, Haemophagidae and Batidae.
Bats have various eating habits. Some species like nectar and fruit, others like to eat fish, frogs and insects, suck animal blood and even eat other bats. Generally speaking, big bats generally feed on fruits or nectar, while small bats mostly prey on insects.
Bats that feed on insects have echolocation systems to varying degrees, so they are called "live radars". With the help of this system, they can fly and catch food in complete darkness, use echolocation under a lot of interference, and send out ultrasonic signals without affecting normal breathing. There are structures called "nasal lobes" on the nose and mouth of their heads, and there are complex special skin folds around them. This is a peculiar ultrasonic device, which has the function of emitting ultrasonic waves and can continuously emit high-frequency ultrasonic waves. If you encounter obstacles or flying insects, these ultrasonic waves can be reflected back and then received by their extraordinary big auricles, so that the feedback information can be analyzed in their tiny brains. This kind of ultrasonic detection has high sensitivity and resolution, so that they can not only identify the direction and locate their own flight path according to the echo, but also identify different insects or obstacles for effective avoidance or pursuit. Bats can fly freely in the air with accurate echolocation and incomparably soft skin membrane, and even fly in a dexterous curve, constantly changing the direction of ultrasonic waves to prevent insects from interfering with their information systems and trying to escape.
Like other animals, many bats are becoming less and less in nature and tend to be extinct. Poisons and wood protectants used to kill insects kill them during hibernation, and many wrong ideas also make humans kill them in large numbers. Some kinds of hollow trees were cut down, and the ruins were torn down or rebuilt tightly, so they could not survive. Bats play an important role in maintaining the ecological balance of nature. All kinds of insect-eating bats can kill a large number of mosquitoes, moths, scarabs, nuns and other pests, and can prey on more than 3000 in one night, which is beneficial to human beings. The excrement collected by bats is also good fertilizer, which is very useful for agricultural production. The processed bat dung is called "night sand" and is a traditional Chinese medicine. Bat is still an important object to study the orientation, location and dormancy of animals, and the secret of its radiation technology has not been fully understood. Humans only know what bats can do, but they don't know how they do it, so it is imperative to save those endangered species.
With the help of bionics principle, human beings made radar according to the echolocation system of bats.
Little knowledge:
1 There are many kinds of bats, about 900 species in the world. The species and number of bats rank second among mammals, second only to rodents.
The wingspan of a small bat with a pig nose is only 1.4 cm, and the wingspan of a flying fox with a body as big as a puppy is 2 meters wide.
Some bats can fly at a speed of more than 50 kilometers per hour.
Bats can capture and distinguish 250 sets of echoes in 1 second. (Note: One round trip of sound waves is counted as one group. )
Since autumn, a layer of fat has accumulated in the lower abdomen of bats, and their weight has become more than 1.5 times that of summer before hibernation.
Some bats can fish, and Mexican harelip bats can catch more than 30 small fish in one night.
An insect-eating bat weighing 20 grams can eat 1.8-3.6 kilograms of insects a year.
Bionics of bat colony composed of 100 bats
Bionics is a word formed by adding ics with engineering significance to the Greek bion with life significance. I started using it around 1960. The function of biology is far superior to any artificial machinery, and bionics is a subject to realize and effectively apply biological functions in engineering. For example, information reception (sensory function), information transmission (neurological function), automatic control system, etc. The structure and function of this organism give great inspiration to mechanical design. Examples of bionics can be cited, such as applying the body shape or skin structure of dolphins (which can prevent turbulence on the body surface when swimming) to the design principle of submarines. Bionics is also regarded as a discipline closely related to cybernetics, which mainly compares life phenomena with mechanical principles and studies and explains them.
Flies are the disseminators of bacteria, and everyone hates them. The wings of flies (also called balance bars) are "natural navigators", and people imitate them to make "vibrating gyroscopes". At present, this instrument has been applied to rockets and high-speed aircraft, realizing automatic driving. The fly eye is a kind of "compound eye", which consists of more than 30O0 small eyes. People imitate it and make a "fly-eye lens". The "compound eye lens" is composed of hundreds or thousands of small lenses arranged in sequence. It can be used as a lens to make a "compound eye camera" and can take thousands of identical photos at a time. This kind of camera has been used for printing plate making and copying a large number of tiny circuits of electronic computers, which greatly improves the work efficiency and quality. "Compound eye lens" is a new type of optical element, which has many uses.
What strange skills do all kinds of creatures in nature have? What inspiration did their skills give to mankind? What kind of machines can humans build by imitating these skills? Here is a new science-bionics.
Bionics refers to the science of imitating organisms to build technical devices, which is a new frontier science in the middle of this century. Bionics studies the structure, function and working principle of objects, and transplants these principles into engineering technology to invent instruments, devices and machines with superior performance and create new technologies. From the birth and development of bionics to just a few decades now, its research results have been very impressive. The advent of bionics has opened up a unique road of technological development, that is, the road of asking for blueprints from the biological world, which has greatly broadened people's horizons and shown great vitality.
Human bionic has a long history.
Since ancient times, nature has been the source of various technical ideas, engineering principles and major inventions of human beings. After a long evolutionary process, a wide variety of biological communities can adapt to changes in the environment, thus surviving and developing. Labor created human beings. In the long-term production practice, human beings have promoted the development of the nervous system, especially the brain, with their upright bodies, hands capable of working, and language for exchanging emotions and thoughts. Therefore, the unparalleled ability and wisdom of human beings far exceed all groups in the biological world. Through labor, human beings make tools with their clever and dexterous hands, thus gaining greater freedom in nature. Human wisdom not only stays in the observation and understanding of the biological world, but also imitates biology by using human unique thinking and design ability, and increases skills through creative labor. Fish have the ability to come and go freely in the water, so people imitate the shape of fish to build ships and use wooden paddles to imitate fins. According to legend, as early as the Dayu period, the working people in ancient China observed fish swimming and turning with their tails wagging in the water, and they put wooden paddles on the stern. Through repeated observation, imitation and practice, it was gradually changed to paddle rudder, which increased the power of the ship and mastered the means of capsizing. In this way, even in the rolling river, people can let ships sail freely.
Birds can spread their wings and fly freely in the air. According to Han Feizi, Lu Ban took bamboo as a bird. "After flying successfully, it will not take three days." However, people prefer to imitate the wings of birds and let themselves fly in the air. As early as more than 400 years ago, Italian Leonardo da Vinci and his assistants carefully dissected birds, studied their body structures and carefully observed their flight. A flapping-wing aircraft was designed and built, which is the first man-made aircraft in the world.
These inventions and attempts to imitate biological structure and function can be regarded as the pioneers of human bionics and the germination of bionics.
A thought-provoking contrast
Although the bionic behavior of human beings has taken shape, before the 1940s, people did not consciously regard biology as the source of design ideas and inventions. Scientists' research on biology only stays at describing the delicate structure and perfect function of organisms. And engineers and technicians rely more on their excellent wisdom, efforts and artificial inventions. They seldom study biology consciously. However, the following facts can show that some technical problems encountered by people appeared in the biological world as early as millions of years ago and were solved in the process of evolution. However, human beings have not got due enlightenment from the biological world.
During the First World War, submarines were built for military needs, so that ships could sail underwater. When designing the original submarine, engineers and technicians first put stones or lead blocks on the submarine to make it sink. If it needs to rise to the surface, they will throw away the stones or lead blocks they carry with them and bring the hull back to the surface. Later, it was improved to change the weight of the submarine by alternately filling water and draining water in the buoyancy tank. Later, it was changed into a ballast tank with an exhaust valve at the upper part and a water injection valve at the lower part. When the water tank is filled with seawater, the weight of the hull increases, so that it can dive into the water. When diving is needed in an emergency, there is also a speed diving cabin. After the hull dived into the water, the seawater in the speeddive cabin was discharged. If one part of the ballast tank is filled with water and the other part is empty, the submarine can be in a semi-submersible state. When the submarine is going to float, compressed air is pumped into the water tank to discharge seawater. After the weight of seawater in the boat is reduced, the submarine can float. Such a superior mechanical device realizes the free ups and downs of the submarine. But later, it was found that the fish's undulating system was much simpler than that invented by people, and the fish's undulating system was just an inflatable swim bladder. The swim bladder is not controlled by muscles, but by secreting oxygen to the swim bladder or reabsorbing part of the oxygen in the swim bladder to adjust the gas content in the swim bladder and promote the fish to rise and fall freely. However, it is too late to inspire and help submarine designers with such an ingenious fish ups and downs system.
Sound is an indispensable element in people's lives. Through language, people exchange ideas and feelings, beautiful music makes people enjoy art, and engineers and technicians also apply acoustic system to industrial production and military technology, which becomes one of the most important information. Since the advent of submarines, it has been followed by how surface ships find the position of submarines and prevent sneak attacks; After the submarine sinks into the water, it is necessary to accurately determine the orientation and distance of the enemy ship in order to facilitate the attack. Therefore, during the First World War, various means were used in the struggle between the opposing sides in the ocean, in the water and in the water. Naval engineers also regard acoustic system as an important reconnaissance means. First of all, hydrophone, also known as noise direction finder, finds enemy ships by listening to the noise made by them when they are sailing. As long as there are enemy ships sailing in the surrounding waters, machines and propellers will make noise, which can be heard through hydrophones and find the enemy in time. But at that time, the hydrophone was not perfect, and generally it could only receive the noise of its own ship. To monitor enemy ships, it is necessary to slow down or even stop completely to distinguish the noise of submarines, which is not conducive to combat operations. Soon, the French scientist Lang Zhiwan (1872 ~ 1946) successfully explored underwater ships by using the nature of ultrasonic reflection. The ultrasonic generator emits ultrasonic waves into the water. If it meets the target, it will be reflected back and received by the receiver. According to the time interval and direction of receiving echo, the direction and distance of the target can be measured, which is called sonar system. The invention of artificial sonar system and its outstanding achievements in detecting enemy submarines have amazed people. Don't you know that bats and dolphins were free to use echolocation sonar systems long before humans appeared on the earth?
For a long time, creatures have lived in nature surrounded by sound. They use sound to find food, avoid enemies, mate and reproduce. Therefore, sound is an important information of living things. The Italian Spalanzanni discovered a long time ago that bats can fly freely in complete darkness, not only avoiding obstacles, but also preying on flying insects. However, after blocking their ears, bats can't move in the dark. Faced with these facts, Palansani came up with an unacceptable conclusion: bats can "see" with their ears. After the end of World War I, in 1920, Hatay thought that the frequency of sound signals emitted by bats was beyond the hearing range of human ears. It is pointed out that the method of bat locating target is the same as the ultrasonic echo method invented by Ron Wan Zhi in the First World War. Unfortunately, Hatay's tip didn't attract people's attention, and engineers couldn't believe that bats had the technology of "echolocation". It was not until 1983 adopted an electronic measuring instrument that it was completely confirmed that bats were located by emitting ultrasonic waves. But this has not helped the early inventions of radar and sonar.
For another example, people study insect behavior too late. 400 years after Leonardo da Vinci studied bird flight and made the first plane, people finally invented the plane in 1903 after long-term repeated practice, making the dream of flying into the sky come true. Due to continuous improvement, 30 years later, human planes surpassed birds in speed, altitude and flight distance, showing human wisdom and talent. However, while continuing to develop faster and higher flying aircraft, designers have encountered another problem, that is, flutter in gas dynamics. When an airplane is flying, the wing vibration is harmful. The faster the flight speed, the stronger the flutter of the wing, and even the wing breaks, causing the plane to fall and many test pilots to die. Aircraft designers have spent a lot of energy on eliminating harmful flutter phenomenon, and it took a long time to find a solution to this problem. The weighting device is placed at the far end of the leading edge of the wing, thus eliminating harmful vibration. However, insects flew in the air as early as 300 million years ago, and they were also harmed by flutter without exception. After long-term evolution, insects have successfully obtained methods to prevent flutter. When biologists study dragonfly wings, they find that there is a dark keratin thickening area above the leading edge of each wing-wing eye or wing nevus. If the wing eye is removed, the flight will become swaying. Experiments show that it is the horny tissue of the wing eye that eliminates the danger of flapping of the dragonfly's flying wings, which is similar to the designer's superb invention. If the designer first learns the function of the wing eye from the insect, and gets a design idea that is conducive to solving the flutter, long-term exploration and personnel sacrifice can be avoided. Facing the eyes of dragonfly wings, aircraft designers have a feeling of meeting each other after a brief encounter!
These three examples are thought-provoking and enlightening. Long before humans appeared on the earth, all kinds of creatures had lived in nature for hundreds of millions of years, and gained the ability to adapt to nature in the long-term evolution of struggle for existence. Biological research can show that the extremely accurate and perfect mechanism formed in the process of evolution makes them have the ability to adapt to changes in internal and external environment. There are many fruitful skills in biology. Such as biosynthesis in vivo, energy conversion, information reception and transmission, recognition of the outside world, navigation, directional calculation and synthesis, etc. , showing the incomparable advantages of many machines. It's really amazing that creatures are small, sensitive, fast, efficient, reliable and anti-jamming.
A bridge between biology and technology
Since james watt invented the steam engine in 1782 (1736 ~ 18 19), people have gained great impetus in the production struggle. In terms of industrial technology, the problems of energy conversion, control and utilization were basically solved, which triggered the first industrial revolution and various machines appeared like mushrooms after rain. The development of industrial technology has greatly expanded and strengthened people's physique and liberated people from heavy manual labor. With the development of science and technology, people have experienced the electrical era after the steam engine and moved towards the automation era.
The appearance of electronic computers in the 1940s added valuable wealth to the treasure house of human science and technology. It handles tens of thousands of kinds of information in people's hands with reliable and efficient skills, and liberates people from the digital and information ocean in Wang Yang. The use of computers and automation equipment can make it easy and labor-saving for people to face complicated production procedures. They accurately adjust and control the production procedures to make the product specifications accurate. However, the automatic control device works according to the fixed program formulated by people, which makes its control ability very limited. Automatic devices lack the ability to analyze and respond flexibly to the outside world. If there is any unexpected situation, the automatic device will stop working or even have an accident, which is a serious shortcoming of the automatic device itself. To overcome this shortcoming, it is nothing more than the "communication" between various parts of the machine and between the machine and the environment, that is, the automatic control device has the ability to adapt to changes in the internal and external environment. To solve this problem, how to accept and transform it in engineering technology is needed. The use and control of information. Therefore, the use and control of information has become the main contradiction in the development of industrial technology. How to solve this contradiction? The biological world has provided beneficial enlightenment to mankind.
In order to get enlightenment from biological systems, human beings need to first study whether there are * * * the same characteristics between biological and technical devices. 1940, the theory of regulation, is to compare organisms and machines in a general sense. By 1944, scientists have made it clear that a series of problems such as communication between machines and organisms, automatic control and statistical mechanics are consistent. On the basis of this understanding, 1947, a new discipline-cybernetics came into being.
Cybernetics comes from Greek, which means "turning". According to Norbert Wiener (1894 ~ 1964), one of the founders of cybernetics, cybernetics is "the science of control and communication in animals and machines". Although this definition is too simple and only a subtitle of Wiener's classic works on cybernetics, it directly relates people's understanding of biology and machines.
The basic viewpoint of cybernetics holds that there is a certain * * * between animals (especially people) and machines (including various automatic devices for communication, control and calculation), that is, there is a certain * * * same law in their control systems. According to the research of cybernetics, the control process of various control systems includes information transmission, conversion and processing. The normal operation of the control system depends on the normal information transmission process. The so-called control system means that the controlled object and various control elements, components and circuits are organically combined into a whole with certain control functions. From the information point of view, the control system is a network or system of information channels. There are many similarities between machines and control systems in organisms, so people have great interest in biological automation systems, and further research on biological systems is carried out by using physical, mathematical and even technical models. Therefore, control theory has become the theoretical basis of connecting biology and engineering technology. Become a bridge between biological system and technical system.
There are obvious similarities between organisms and machines, which can be manifested in the study of different levels of organisms. From simple single cell to complex organ system (such as nervous system), there are various physiological processes of regulation and automatic control. We can regard the organism as a machine with special abilities, which is different from other machines in that it also has the ability to adapt to the external environment and reproduce itself. You can also compare an organism to an automated factory, and all its functions follow the laws of mechanics; Its various structures coordinate their work; They can make quantitative responses to certain signals and stimuli, and they can contact the organization through special feedback like automatic control to adjust themselves in a self-controlled way. For example, our constant body temperature, normal blood pressure and normal blood sugar concentration are all the results of the complex automatic control system in our body. The emergence and development of cybernetics has built a bridge between biological system and technical system, and made many engineers consciously seek new design ideas and principles from biological system. Therefore, there is a trend that engineers take the initiative to learn biological science knowledge in order to achieve results with biologists in the field of engineering technology.
Oh ~ it seems a little too much. I'm just looking around.