People always like to predict the future world, so there are a variety of science fiction works, later, the human world can no longer meet the imagination of the play, after the disappearance of human beings, the world dominated by whom?
Some people say that monkeys are called kings, some people say that wild boars arch everything, and some people think that rats with super adaptability are the real kings of the last days, after all, even cockroaches can be on top of their recipes.
This vision of the future seems to hint at the relationship between human and animal competition and constraint, and even rats with high hopes are not comfortable leaving the human world.
This year's epidemic has made rats in the streets of the United States very uncomfortable, because restaurants have closed down on a large scale, and people's opportunities to eat outside have decreased. The rats were so hungry that they poured into the streets to kill each other.
Rats on new York subway tracks
Rats that seem to depend on humans seem to be just parasites in the human world, but even parasites have times to manipulate their hosts, so the impact of rats on humans is far beyond your imagination.
Today we will talk about the war within the rats, a war that even ended the black death of human beings, affecting human life and death.
First of all, of course, we must understand that there is not only one kind of rat that parasitizes the city, they basically occupy all the space in our city, from the inside of the ceiling of the building fume pipe to the sewer of the stinky ditch flower bed.
One of the brown house mice we are most familiar with is the brown house mouse, which has gray-brown body hair, a strong body, and likes to appear near stinky gutters and garbage dumps, and its hair is often dirty, and it often swings out at night to forage.
The brown rat basically contracted all the disgusting negative imaginations about rats, which came from northern China or Inner Mongolia and were already the strongest in the region before humans began to settle.
In the wild, brown rats eat everything, prefer animal foods, and can prey on frogs, insects, lizards, and even other small mice. With human activities, household garbage became an important source of food for them, and they began to expand their territory.
Brown rats on Chicago street sewer probes
Until the 18th century, the brown rat did not make a large-scale move out of Asia. At that time, Europe was fighting one of the worst plagues in history, the so-called Black Death, which lasted from the 14th century to the 18th century and swept across Europe, killing more than 25 million people.
From today's knowledge and God's perspective, the source of the Black Death may have come from another asian rat, the black rat, and it is currently speculated that merchant ships that traded along the Silk Roads brought the pathogen to Europe.
In short, the black rat "colonized" Europe first, and brought with it the pathogen of the plague, Yersinia bacillus, which tormented the European continent for 4 centuries.
The black rat has a dark coat and is also called a roof rat if it likes to climb
In 1727, the brown rat was brewing a "great" river crossing. Not long ago, there was a major earthquake in India (inaccurate records were not found), and the rats in India detected the crisis in advance, escaped from their nests, and then ate on human corpses, and the number soared.
But after the disaster, the population decreased and the household garbage provided to the rats was also reduced, and the large number of rats that had previously fed on corpses could not survive, so they began to migrate westward, and in 1727, in Astrakhan, an army of millions of rats was seen crossing the Volga Like a carpet and landing on the West Bank to successfully reach Europe.
The brown rat is good at swimming
The war between the two rats is on the verge of breaking out. In Europe, the newcomers killed brown rats, and the reasons are not difficult to understand. First of all, the living habits of the two kinds of house rats are more similar, the feeding and activity space are relatively overlapping, but the brown rat is larger, and has a great advantage in direct fighting, so it can often grab more food, and the brown rat breeding rate is also faster, so the brown rat population expands rapidly in Europe, replacing the position of the black rat.
The black rat was beaten away, and the black death was gone? It's not that simple, both black rats and brown rats are also native species in Asia, and they are also natural hosts of plague, and the source of plague does not disappear because brown rats replace black rats.
The key lies in the spread of plague. According to the current mainstream view, the epidemic of the Black Death in Europe is inseparable from the spread of fleas, it is generally believed that the transmission process of plague is probably like this, first of all, there needs to be mice infected with plague, and fleas parasitizing on the surface of the rat body will also carry Yersinia pestis because they suck the blood of the host, and when the rat dies, the fleas carrying the germ will look for new targets, these targets are generally other individual mice, but there will also be humans.
This is true for the black house rat and the indian rat flea on them, but it does not hold true on the brown house mouse. Parasitizing the surface of the brown rat is another type of fleas under the family Fleae, unlike the Indian flea, which only looks for another mouse after the death of the host, rather than selecting humans.
Males have diseased fleas and belong to the family Fleaceae
A research paper published in 1914 found that horned fleas are not only more specific to a specific host, but also can reproduce normally only after sucking the blood of brown rats, otherwise the males will only die alone.
A "million male masters crossing the river" of the brown rat indirectly quelled the Black Death, which is difficult for humans to imagine, so that Europeans realized that the brown rat was from Norway, so the name "Norwegian rat" was initially given.
Top to bottom: Norwegian rat (brown rat), roof rat (black rat), small house mouse
Of course, the end of the large-scale epidemic of the Black Death must have been caused by a variety of reasons, including the end of the Xiaoice River period, the climate became warmer and wetter, people's hygiene habits improved and demographic changes, and so on.
However, the Black Death disappeared and the brown rat flourished. The humid and warm climate is more suitable for brown rats, coupled with the fact that countries began to build underground sewage systems in the 18th century, brown rats defeated black rats in one fell swoop, dominating Eurasia, of course, the Americas and Australia soon fell.
The brown rat has become the most familiar rat in modern and modern humans, and many characters based on rats have also chosen the brown rat, such as the famous American anime Teenage Mutant Ninja Turtles who lives in the sewers, Mr. Sprint, who is obviously a humanoid brown rat.
Including mice and rats often used in medical or biological experiments, among which the rat is bred from the brown rat, and the chipmunk that enters the pet market is also a brown rat that is artificially domesticated and selected.
Fat flower rats
So, the brown rat is invincible? No, the rat civil war continues, nearly 300 years ago the brown rat defeated the European black rat, and today, the old cousin of the black rat, the yellow-breasted rat, has a tendency to seize power in East Asia.
Yellow-breasted and black rats have more akin to life habits, climbing, nesting in high places, traditionally mainly distributed in the southern region, and have expanded rapidly northward in the past 20 years. With China's rapid urbanization, the popularization of buildings, the hardening of the ground (unable to punch holes), and the transformation of the sewage system, these have all had a negative impact on the survival of the brown rat.
On the other hand, the yellow-breasted rat jumps up and down, climbs up ten floors along the water pipe, and nests in the ceiling, making life more moist. This civil war of rats has clearly entered a new phase, but in the end it is we humans who are uncomfortable.
You may have heard the elders lament that the rats in the past were much more stupid than they are now, and simple traps can be caught, and the rats are indeed becoming more and more refined passively, but the more core is the replacement of the rat species.
Common rat houses often only poison gluttonous brown rats
Brown rats are large, clumsy, more gluttonous and intolerant of hunger, can be killed by putting poisonous bait outdoors, and yellow-breasted rats, which are often active indoors, are cunning a lot, easily do not eat strange food, and are more flexible in the face of sticky rat cages, often eating the bait and retreating.
If you do not understand the complexity of the rat civil war, simply killing the rat blindly is likely to be counterproductive. Why is it so, a single means is often difficult to eliminate the yellow-breasted rat, but the middle trick is the brown rat, which is equivalent to helping the yellow-breasted rat win the civil war.
Yellow-breasted rats in the wild
As a result, the hard work of catching mice may have caught a few, but the traces of rats at home did not disappear, but went crazy, because the opponent was eliminated, and the survival pressure of the yellow-breasted rat was less.
In addition, the Institute of Zoology of the Chinese Academy of Sciences also found through experiments that after long-term interspecific odor mutual stimulation, the odor of male yellow-breasted rats became more sexually attractive, while the odor attraction of male brown rats weakened, which means that when two kinds of rats live in the same environment, the fecundity of yellow-breasted rats may be improved, and the fecundity of brown rats is reduced.
Yellow-breasted rat (left) and brown rat (right)
In short, rats, the "lowly" animals that parasitize the human world, are not simple, and their every move can greatly affect the human world.
To put it more exaggeratedly, Europeans who have been tormented by the Black Death for 4 centuries are like falling leaves in the water, just pushed back to the shore by the waves stirred up by the million rat army that crossed the river; to put it mildly, the conspiracy theory is that we have exhausted all means to exterminate rats today, which may be nothing more than the east wind borrowed from the rat civil war.
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