Unheard animal weird

Lonely ants die fast

  Loneliness can make people feel depressed, and the pressure can’t be relieved. In the long run, it will have a negative impact on people’s health. Researchers have also found that some vertebrates, such as parrots, die young when they are isolated. However, what is unexpected is that even invertebrates-ants will die of loneliness!
  Researchers at the University of Lausanne in Switzerland did an experiment. They prepared isolation rooms with food and water, and a box that could act as an ovary. After everything was prepared, the researchers put a group of African ants into the isolation room. Some of these ants live alone, some live in groups.
  The final research results are very dramatic. The average lifespan of ants living in groups of 10 is 66 days. The average lifespan of ants living with larvae or in pairs is 22 days and 29 days, respectively. Ants living alone die after 6 and a half days. Why is this?
  The researchers found that these solitary ants were more active and crawled around. They eat as much as social ants, but most of the food is stored in the crops and not digested. The solitary ants are starved to death.
  Crops are organs in the abdomen of ants that store the food they find. When they return to the nest, they will ruminate the food to feed other members of the population. After feeding other members, the food left in the crop will be digested.
  However, it stands to reason that ants living alone do not need to share food with other members. They should be more nutritious. Then, when there is so much food, why do ants living alone choose to “hunger strike”?
  Researchers speculate that it may be caused by stress, or it may be that the fluid exchanged with other members stimulates digestion when the ants are ruminating food. Researchers can’t explain the specific reasons. Researchers from the University of Lausanne in Switzerland are now collaborating with researchers from the University of Tokyo to study how living alone affects the gene expression of insects, hoping to figure out how loneliness disrupts the digestive system of ants.
Why do animals face north and south when they eat?

  Google Earth is a virtual globe software launched by Google. This three-dimensional model collects many satellite photos, aerial photos, etc., and provides users with real-time geographic information of millions of locations. Users can browse the entire earth online. Explore the unknown world.
  Scientists are also using Google Earth. In 2008, researchers from the University of Duisburg-Essen in Germany used satellite photos from Google Earth to analyze the location of 8,510 cattle in 308 ranches around the world. In the end, they found that 60% to 70% of the cows, whether grazing or lying, always face the earth’s north-south magnetic field, just like a mysterious religious ritual of a herd of cattle.
  The first reaction of the researchers was that cattle also have the ability to align their bodies with magnetic poles. In nature, many animals have this ability. For example, a dog likes to have its body aligned with the north-south direction of the geomagnetic field when it poops. Some animals will face the north-south direction when resting. Bees, fruit flies, zebrafish, bats, foxes and some rodents all exhibit similar behaviors.
  For a long time, people have known that animals can use magnetic induction to navigate and realize long-distance migration, but there is not much research on this ability to align their bodies with magnetic fields. So why do animals do this?
  Some people think that this is because animals are trying to avoid the cold wind, but this is unlikely, because if this is the case, the wind direction should be different in different regions and climates. These animals distributed around the world have their bodies arranged in directions. It should be random, not biased towards north-south.
  Now a more scientific explanation is that for ruminants like cows, the magnetic calibration of the body helps individuals in the group to maintain synchronized movement, avoiding the overlap of the eaten grass path and the uneaten area. It can also help cattle and deer to escape from predators in an efficient and coordinated manner. Or, magnetic calibration can help animals remember information in the environment and learn new road signs.
  Some scientists have also proposed that magnetic calibration may affect the physiological processes of animals. In previous experiments, the researchers found that people who sleep east-west will have shorter REM sleep periods than those who sleep north-south. The REM sleep period is the last stage of our sleep cycle. Sleep at this stage helps to improve memory and stimulate the development of the central nervous system. Therefore, animals may be using magnetic calibration to make their bodies healthier.
Rat Utopia

  For animals, the best life is probably not to worry about hunting by predators and to eat and live. Therefore, in the 1960s, American animal behaviorist John Calhoun designed a famous mouse utopia-“Universe 25”.
  In the experiment, Calhoun set up an exquisite serrated animal room, which can accommodate a total of 3,000 mice. Subsequently, the researchers put 4 pairs of mice in the room and provided them with unlimited amounts of water and food. The temperature-controlled room was kept clean and the health of the mice was monitored. Rats have a worry-free life, have comfortable shelters, do not have to work but have food to eat, and do not have to worry about weather changes, predators, and the threat of diseases. It is almost like living in a utopian world.
  As expected, after 104 days of getting used to the new environment, the rats began to multiply, and by about 315 days, their number reached 620. However, as the number of rats increased, they also began to exhibit very strange behaviors. They gather densely in a small area and start cannibalism and chaotic intercourse. Those mice with no social status do not fight or have sex at all, which also causes females to come forward and guard the territory like males. The females became more violent, some refused to mate, neglected to care for the pups, and even attacked and killed the pups. These abnormal behaviors have led to a rapid decline in the birth rate of rats, and the mortality rate of young rats in some areas exceeds 90%. Even if the newborn mice survive, the new generation who grew up in abnormal social relationships will behave like “walking corpses”, neither fighting nor courting, but just dressing up and narcissism, Calhoun will be this generation The formed society is called the “beauty-loving generation”. Although they have rat bodies, they no longer have rat behavior. At 560 days, the number of rats reached a peak of 2,200. They began to stop breeding, the number steadily declined, and finally went extinct, and the utopian society of rats fell apart.
  Some researchers have speculated that the reason why mice stopped breeding is because the living space is too narrow. But what remains to be explained is why the rat society cannot return to a normal state after the number of rats has decreased?
  One guess is that mice, like humans in many ways, will lose their sense of self-identity and goals without any pressure. Because there are too many resources, no action is needed to obtain these resources, social role-playing no longer exists, and they have no motivation to socialize and mate.
  Others believe that the gene mutation rate of mice is extremely high. The mice in nature are easy to die, leaving healthy male offspring to reproduce. However, the number of mice in the universe 25 was too small and the genetic diversity was reduced, so they could get the probability of mutated genes. Will be taller and easier to die.