They live in more complex cities, and they have a variety of threats. They are close to human beings and are always interested in new things. That is why urban birds have become smarter. In order to adapt to urban life and live more safely, the bird of the city becomes more and more developed and evolves faster than country bird. Photo: crows in Sendai, Japan can crush walnuts with cars. A rickety cement wall, a slope, a wide asphalt road, and several silvery cars are slowly driving around the conical traffic signs. In the view of urban biologists, the Sendai in Sendai, Japan (Kadandrivingschool) is a holy land. Four of us (including biology students MinoruChiba and YawaraTakeda, biologist IvaNjunji, and the author of this article, Menno Huschuisin (MennoSchilthuizen), an evolutionary biologist at the center for natural history of natural history at the Leiden University in Holland) now have been sitting on the wall for several hours hoping to observe this place. Something to be famous. Here, the local carrion crow (Corvuscorone) discovered how to use the car as a nutcracker in 1975. These Ravens prefer Japanese walnuts that are growing in cities, but for them, it is hard to smash these beautiful nuts (smaller than ordinary walnuts, with a beautiful heart inside), and their beaks may even be broken. So long ago, they threw the walnuts from the air onto the rocks and broke them by gravity. Anywhere in Sendai, you can find ubiquitous empty shells in the parking lot: crows either throw them in the air or bring them to the top of adjacent buildings and throw them into the underneath the asphalt road below. But even for crow, these repeated flights and landings are exhausting. Sometimes nuts need to be thrown repeatedly for several times to break. So, at some point, the crow came up with a better idea. Crows will put walnuts in front of slow wheels, then pick up the flesh after the car drives. This behavior starts with the cardan driving school, where there are plenty of slow cars. Since then, this method has been imitated by crows elsewhere and has gradually spread to the whole city. In Sendai, slow moving giant nutcrackers are very common, such as sharp corners on roads and crossroads. In such a place, crows will stand on the roadside and place nuts on the road more accurately instead of dropping them from the air. Since then, this trend has also appeared in other cities in Japan. In 1995, YoshiakiNihei, a zoologist at Northeastern University in Sendai, conducted a detailed study of this behavior. He watched how the crows waited near the traffic lights: they waited for the red light, then went to the front of the car, put the nuts away, and finally jumped back to the roadside for the green light. When the vehicle passes by, crows will return to the road to get their pulp. YoshiakiNiheis research reveals the Ravens wrist when dealing with their tools. For example, if a walnut is not pressed by the wheel for a long time, it sometimes moves a few centimetres of walnut. In one case, YoshiakiNihei even saw a crow go in front of a coming car, force it to brake, and quickly throw a walnut in front of its wheel. It was not until the 1997 that these fascinating observations aroused concern in relatively obscure Japanese scientific papers. That year, the Broadcasting British Corporation (BBC) program came to Sendai to shoot a crow for the David Atenborough (DavidAttenborough) series of documentary TheLifeofBirds. His voiceover made many people instantly shocked: they (crows) stand on the walkway, waiting for the traffic lights to change. Then, the nuts are collected in a safe place. So, in this city, our four person team is going to spend the whole day watching the crows in person. MinoruChiba and YawaraTakeda tell us that the Raven trick is very famous in the locals. In fact, watching the crow throw nuts is a popular local pastime. We brought walnuts from Holland and decided to try our luck. But the crows do not match. We have spent the whole morning at the traffic lights of the crossroads, sitting foolishly in the canvas folding chair and waiting for countless car drivers. But so far, these efforts have been futile. Now, these walnuts are not mature, and crow young birds just fly, and crows plunder other things in the city, such as the ubiquitous mature mulberry. I sighed and looked at it for a while. Then, I heard a crackling sound in the back of my body. I turned around and saw that IvaNjunji had begun to eat our walnuts. She looked at me provocative, and said, anyway, they will not come. Carrion crows are not only found in Japan, they also exist in Western Europe, where you can find plenty of cars, crosswalk and walnuts. However, in Europe, carrion crows do not know why they have never learned to use human motor vehicles like their Japanese counterparts. However, this is not to say that European humans are immune to bird behavior. Local songbirds skills of bottle feeding have lasted for nearly a hundred years. These tits are divided into yellow, black, blue (blue tits) and olive green (great tits). In fact, all birds (including tits) cant digest milk. Unlike mammals, they lack the enzymes needed to break down lactose. However, there is a layer of cream on the top of the old, uneven milk container, which contains only a small amount of lactose. In winter, hungry birds will get rich butter to supplement their fat intake. This was what the tits did in Britain and other parts of Europe in the late nineteenth Century and early twentieth Century, when milkmen were still used to putting the bottles of milk on the front steps of the customers door in the morning. Before the residents open the door to the safe place, the tit swooped over, landed on the neck of the bottle, put its mouth in the cream inside, and ate the coveted food (about 2.5 centimeters). When the milkman found the behavior of the tits, they hurried to the front door without giving the tits any chance to steal the cream. And tits are unwilling to close their hands. They will stroll around peoples homes and want to take the lead. In any case, at some point in the early twentieth Century, milk suppliers began to close their bottles with wax bottle caps. This is a temporary solution, because in 1921, in Southampton, the tits began to pry them open, or peel the cardboard on one floor, until the lid was thin enough to be pierced by the beak. The replacement of a cardboard cap to an aluminum cap did not work too long: by 1930, the tits had learned how to open a metal bottle cap in 10 different towns and cities all over England. When facing the metal bottle cap, they will punch a hole in it and tear the foil. They may also lift off the entire bottle cap and fly away, cling to the lid of a bottle with a claw, then go to a remote place and peck at the butter that is stuck to the cap. Under the tits favorite tree, the discarded caps gradually pile up. Cinder and Fisher learned this in 1947 because, in a civil science program, they sent hundreds of questionnaires to bird watchers, naturalists, milkmen and milk consumers, and also sent questions to doctors and other trained people. By receiving responses, they combined the skills of the tits to open the bottle and the detailed history of human responses, which spread throughout the British Isles and throughout the continent. When the milkman returns to the car, the other tits will fall on the bottle they just sent. In an article in BritishBirds in 1949, they published some of the responses they had received, which revealed the frustration of human beings in the fighting with the tits. People are annoyed at the speed of the tits opening bottles. They usually act within minutes of milking, as if they always wait there. Sindh and Fisher published maps in their articles to show how birds bottle opening skills were disseminate. Interestingly, they are not gradually spread from the source of bird innovation in Southampton. To be more precise, the attack of bottles by a tit in many towns and cities seems to be an independent act, and this behavior will only prevail locally. Within a year, the tits rarely move more than 10 to 20 kilometers, and a new town, more than 20 kilometers away from the affected Town, is suddenly tortured by the starving tits. Therefore, it is more likely that this behavior was invented by the more intelligent tits, and was imitated by other birds. For example, in Welshs La lane, it is hundreds of kilometers away from the nearest learned tit. In 1939, only one household in 300 households was attacked by tits. But 7 years later, all the tits in this community learned to bottle up skills. In Amsterdam, Nicole Tinbergen, an NikoTinbergen, saw the great tits open milk bottles before and after World War II and even during the war. A few years later, milk was no longer delivered. No pre war tits survived until 1947. In the past decades, the tits seem to have been defeated by their human counterparts. First of all, skim and homogenized top of the milk no longer have cream residue, they also become more popular. For a time, tits tried to avoid these problems by distinguishing the color of traditional high fat milk bottles. But since then, aluminum bottles have been slowly replaced by other containers, and the mobile milkman has almost disappeared and replaced by supermarkets. Nowadays, few homeowners have experienced the experience of their milk being destroyed by birds. The ongoing struggle between birds and bottles has always inspired urban biologists, because many mysteries still exist. How does the bottle - opening technique spread among birds? Are urban birds better or faster to learn these new tricks or acquire new tastes than country birds? If so, what is the reason? For the first question, how clever birds learn new tricks and pass it on to the same kind, Australian researcher Lucy Appling (LucyAplin) at the University of Oxford found the answer. Applin studied in WythamWoods, near Oxford. She set up an automatic computerized puzzle box in the forest. Puzzle Boxes are a roundabout assessment method for biologists to solve problems in animals. It is usually a delicate device. Birds need to take a series of actions, and then get delicious food as a reward. Applin studied the tits, which consisted of a plastic box and a stick. Sticks can act as gateways, and tits can glide right or left through their beaks. Behind the door, birds will find delicious live worms. Thats not all. Due to the restless biologists, the great tits in the WIMS forest are closely scrutinized. For example, every big tit has tiny transponder chips on its legs. By placing antennas on nest boxes and feeding tables, researchers can track individual history of each bird, for example, how large is it? Who built the nest with? Who is its friend? And what kind of people does it like to go out with? When each big tit falls to the ground, these personal identification codes will be captured by the antenna hidden in the appling Riddle Box. If the bird tries to open the plastic door, the switch on the door will be registered, and a key point (well see) is that it can detect the method used by the big tits and push the plastic doors to the left or right. The Wake Forest is divided into 8 parts, at least for its big tits, with about 100 big tits in each part, and they interact more than other birds in other regions. Observers at University of Oxford called them sub groups. In 5 subspecies, applin captured two male great tits, giving them the distinction of using the early adopters of the puzzle box. Applin taught these 10 birds how to open the Mystery Box and let them observe the behavior of captive birds that already know the tricks. Some of the birds she trained opened the door on the right, others opened the left door, and she ensured that two birds from the same subgroup learned the same skill (either push left, or push right). Obviously, the knowledge is transmitted through the network of subgroups through the network of friends: the best friends of the enlightening bird will first learn the skills, and then gradually expand the spread of the new knowledge. As the Riddle Box records the exact moment that each bird has learned the skill, it can actually observe the pattern of its spread throughout the social network of birds until almost all birds have mastered this technique. This is the two alternative to the right push door or left push door solution: in each subspecies, the tradition of opening the door depends on how the original bird of inspiration was trained. If they learn to push the door to the right, all birds in their subspecies will eventually do so, and vice versa. Even a year later, applin found that the local habit of opening the box still existed. The greatness of Britain is that some animals can learn how to crack the human code, and then let their best friends know the secret, at least before people come up with a solution. This is a frequent conflict between the human and the animals living in the city, but in order to get this information to be learned and transmitted in animals, some of the animals abilities are essential. First, animals need to have the wisdom to solve the problem, which helps the blue tits and the big tits understand that the aluminum bottle cap on the bottle can enjoy the delicacy of the cream. Secondly, animals need to have new addiction, that is, to be curious about the unknown. When the first batch of glass bottles appeared, some tits were not frightened by them, but began to explore the nutritional value they might contain. Finally, animals need to tolerate angry milkmen, waving their clothes to drive out their landowners, and dare to engage in close contact with ordinary people. Obviously, those tits that have been successfully attracted by the bottle or the appling puzzle box benefit from their tolerance and new abilities to solve problems. But its not always the case. In a more natural environment, it is often safer to remain shy, conservative and dislike new things. In a long-term and stable environment, humans and other large animals can avoid meeting each other better, because they may be the threat of each other. Human made objects often have fatal parts, so safety is better than regret. But in cities, traditional behaviors may need to be reconsidered. Human beings bring a lot of food, they create shelters and nests, and usually provide new opportunities. In addition, at least in cities, humans tend to be fond of most small birds and mammals and are unlikely to harm them. In the end, human beings are always creating new things. Sometimes, like McFlurry ice cream cups, hedgehog will be stuck inside. These new things are dangerous, but usually they have more advantages than disadvantages. In other words, we may think that urban animals will evolve better by making better use of our neighbors. This is not because the tits have some open - bottle genes (certainly not the existence of this gene), but because genetic tendencies are tolerable and more curious (these genes do exist), which will help animals quickly learn how to make use of humans and their changing lifestyle. By speeding up learning, such genes will spread. Compared with those living in the countryside, this species will evolve smarter in the city. In fact, there is evidence that urban animals are fearless problem solvers and have preferences for anything new. Some of the evidence comes from Barbados. Mcgill University in Montreal, Canada, has a field center there. At the edge of Brighton City, several generations of teaching staff and students from Mcgill University are doing field teaching and graduate research projects there. The field center has a very good canteen, but it is on the sunny Caribbean coast, and the luxurious ColonyClub is next door, so a few hours of field work can relax and rest here. On 2000, on the ColonyClub table, several Mcgill University biologists first noticed that the brazen Barbados grey sparrow (Loxigillabarbadensis) could cleverly open the sugar bag for human consumption. Just like the blue tits in Britain, milk flasks are opened, and the red bellied birds take up a candy with a claw. Then they use their thick beaks to tear the paper packaging, swallow a few sweets and fly away. After that, the red bellied gray bird was seen to master several other table manners, such as opening the sugar bowl (lifting the heavy ceramic cover with the mouth) or stealing coffee cream. Graduate student Jean Nicholas Audette (Jean-NicolasAudet) says that when you sit on an open platform in Barbados, you can almost guarantee that you are going to be with the gray sparrows. For Audette and his colleagues at the University of Sydney, Simon Dukatez (SimonDucatez), the study of the behavior of these red gray sparrows has provided a much - needed reason for their longer stay on the ColonyClub table. In the end, they even convince their bosses to do some live work in the club. There are nearby CoralReefClub, gorgeous RoyalPavilion and so on. But Barbados is not always a city and a seaside resort. Although the population is large enough and the level of urbanization is high enough, the northeast corner of the island remains rural. Therefore, Audette believes that if the technique of solving the problem of the red belly sparrow in the rural area is comparable to that of the city, it may be very interesting. In order to study this problem, Audette designed two types of puzzles. They are made of transparent plastic and have seeds as a reward. But one of them (drawer box) can be opened by pulling the drawer or pulling the lid off, while the other Mystery Box (tunnel box) requires two steps -- first pull and pull. Audette captured 26 red grey sparrows and 27 rural gray sparrows in the city and tested them in the field center to see if they could open the riddle boxes if they could. It turns out that all birds can open drawer boxes, but the speed of city birds is two times that of country birds. The more complex tunnel boxes were only opened by 13 city red sparrows, while the countrys red grey sparrows were worse, only 7 were successful, and they spent almost 3 times as much as the citys birds. Obviously, city red birds are better at devising new ways to get food from human beings. Compared with rural counterparts, whether city finches actually carry different genes to solve the problem remains to be discussed. But if the benefits are large enough, natural selection can still flow upstream and gradually form genetic differences. Solving problems is the primary trait. But even for animals to solve a problem, they need to be cautious about new things and unfamiliar objects in the environment. In addition, it needs new love addiction (curiosity), which is keen to approach and investigate any unusual things. Over the years, experimental biologists have conducted many different experiments to test the new addiction of urban animals. What is more interesting than trying to piece together strange objects that dont look like anything, and experiment with unsuspecting animals? For biologists, its like a candid camera. British crows can be pieced together with crisp bags, jams and polystyrene fast food containers. The American tits in Tennessee can be built with Duplo blocks. In almost all cases, urban birds are closer to these strange objects and are more interested in them than the cautious country birds. A particularly in-depth study is worth mentioning. Piotr Tyganovoski (PiotrTryjanowski) of the Poznan University of life science and his colleagues studied 160 bird feeders in and around Poland. Half of the feeder is decorated with bright green and mixed hair gum. We have never observed anything similar in the field, they wrote in a 2016 scientific report. The response of the local birds to this object is that it is almost impossible to be a novelty. Other feeders were not modified, and four species of birds (tits, blue tits, small golden wings, and tree sparrows) visited them most, and rural tourists usually had fear of new disease: they avoided exposure to the weird green feeders on the roof. In the city, there will be the opposite. Here, birds actually flock to the freshly colored feeding table. With the wisdom of solving problems and the fear of new characteristics, the third and last individual character of the urban environment is tolerance, that is, to reduce the fear of human beings. In the 2016 article in the field of ecology and evolution (FrontiersinEcologyandEvolution), the team led by Matthew Simonds (MatthewSymonds) of the Deakin University, Australia, contrasts the so-called runaway start distance (FID) of 42 different birds, that is, the level of the flight of humans before they approach the birds. Average distance. They found that among all these birds, city birds were more tolerant of human beings than country birds. Moreover, the longer the birds live in the city, the greater the difference. For example, Corvusmonedula, a city living in the city, entered the city in 1880s. When humans are close to 8 meters, they will be frightened to take off. In rural areas, they take off 30 meters away. On the other hand, the big spotted woodpecker (Dendrocoposmajor) began to be urbanized in 1970s, but there are still similar FID in urban and rural areas, 8 meters and 12 meters, respectively. This suggests that tolerance has actually evolved. As time goes on, it is not possible to realize that every generation of birds should be more bold than their parents to respond to the people around them, and you would want this to happen faster. More precisely, if the benefits of higher tolerance can be tolerated, the genes of tolerance will gradually accumulate and the characteristics of species will also evolve. Such an explanation is likely to be correct, because the researchers also found that the tolerance of birds is not related to the size of the brain: smart birds are not much more tolerant of humans than other birds. Solving problems, new addiction and tolerance are likely to be the result of urban evolution, and in the continuous arms race with urban humans, these animals have been able to gain access to food and other resources. These are the first kind of intimate contact, and when evolution reaches a perfect level of adaptation, evolution may stagnate. Source: NetEase science editor: Guo Hao _NT5629 This suggests that tolerance has actually evolved. As time goes on, it is not possible to realize that every generation of birds should be more bold than their parents to respond to the people around them, and you would want this to happen faster. More precisely, if the benefits of higher tolerance can be tolerated, the genes of tolerance will gradually accumulate and the characteristics of species will also evolve. Such an explanation is likely to be correct, because the researchers also found that the tolerance of birds is not related to the size of the brain: smart birds are not much more tolerant of humans than other birds.