I have some insights about this issue. In real life, there are a lot of families who choose to keep pets, and there are many of them who have cats as pets. With the development of the times, jerking cats has also become a favorite thing for most people, but in the countryside, cats are treated as a handful of catching mice. It may be genetically suppressed that even very small cats can catch mice bigger than themselves. So the existence of a pair of natural restraint between cats and mice has also been recognized.

But with the development of urbanization, the reality is that there are fewer and fewer rats, even in the countryside, we will rarely see rats, not to mention the big rats. For the status quo of rats, many people also raised doubts, why the rats are now less and less, and most of the size is also very small, this is caused by the evolution of rats?

In our lives, if not specializing in the study of rats, it is difficult to understand that there are many types of rats. According to biology, there are more than 1,793 species of rats, and there is also a huge disparity in size, with the larger ones growing up to 50 kilograms while the smaller ones are only about 5 grams. In the home, the mouse is not too detailed species division, usually is the distinction between house mice and wild mice, but this distinction is more ambiguous, so generally house mice are divided into small house mice, brown house mice and black house mice.

1, fewer and fewer people living in the countryside

With the development of urbanization, more and more people are running to the city, which also leads to less and less people in the countryside. Now a lot of rural families only left some of the elderly, and the elderly also thought that the physical reasons, so most will not choose to planting, there is no cantonment of food. Slowly the rats also have no food source, in order to survive, and eventually gradually left the countryside.

2, the home environment is not suitable for rats

The reason why the rural or urban areas are not suitable for rats to live in, the main reason is that people's standard of living has improved. A long time ago, people's homes would be stocked with food, and there was a big problem with food storage, so there were many ways that rats could get food. But as the standard of living has improved, people don't need to stock up on food, and food can be stored in a more organized way so that rats can't find food, so homes are now unsuitable for rats to live in.

Generally large rats like the black and brown house mice, they need a lot of food, but nowadays there are not many families that will randomly place food, so these rats can not find food, survival becomes difficult, and eventually gradually away from the places where humans live. However, rats are still plentiful in some food establishments or dumps where food is piled up.

3, competition and the environment lead to the existence of small rats

Now many families do not have a large number of stored food habits, large rats can not perhaps more food, so away from the place where people live. The reason why we see most of the rats are very small, this is because small size is very easy to hide, and now the home decoration is relatively clean and tidy, small rats can find a place to survive. And small mice do not need a lot of food, so now most of them are small mice. This may be the survival of the fittest!

For the places where we live, especially in the buildings of the city, even small mice are not seen much, after all, nowadays the technology of catching mice is very advanced, and mice will not take life to fight against human beings. This is the choice of rats, but also the result of the changed environment.