The economic vitality and living standards of some large and medium-sized cities in China have reached a considerable level. Compared with some small towns or cities in the west, they can provide more favorable treatment and better development space for college students. Of course, graduates will choose to stay in big cities or coastal areas as much as possible.

(2) changes in the employment situation

With the unprecedented increase of employment pressure in China, the number of college graduates has increased year by year. At the same time, our society is experiencing a series of structural changes, such as urbanization, demographic transition, labor market transition and higher education system reform. Under the comprehensive effect of these factors, it is inevitable for college graduates to stay in cities in China, especially in big cities.

(3) Advantages of various conditions

Low rent and convenient transportation are the objective reasons for the formation of ant tribe. With the gradual implementation of various management measures in the central city and suburbs, the floating population will inevitably migrate to the surrounding areas of the city. At the same time, because of convenient transportation and low cost of living, there are relatively more land that can be developed and utilized, the speed of development and construction is accelerated, and there are relatively more opportunities for employment and entrepreneurship. In addition, a large number of rental houses built legally and illegally in these areas make it possible for newly graduated college students to settle here, which is bound to form a settlement here.

(4) Pursuing an independent life

The pursuit of independent life leads a small number of students to choose to live in their village. Among them, some college students live in their own villages because of their personality defects. These students are either not good at dealing with classmates or are not used to collective life.

Because young people in colleges and universities come from different regions, roommates have some differences in living habits and hygiene habits, so it is often difficult to integrate in collective life, and even conflicts or disputes may arise. So some students avoid it with the mentality of "not to be taunted, but to hide if they can" and create their own living world and free space outside school.

(5) the demand for gathering space

Pursuing the identity among groups is the subjective reason for the formation of ant colony. College graduates have just entered the society, and familiar people can give them greater sense of security. So they often contact their brothers and sisters on the eve of graduation, hoping to live in the same area with them, and over time they form a settlement village.

At this time, the settlement village is like a relatively familiar harbor, and the tired ships of graduates will break down in the harbor and flee. No matter whether the harbor agrees to accept it or not, no matter whether the harbor can bear it or not, the ships taking refuge are crowded in.

Compared with the large number of ants in real life, ants are a little-known group in terms of social attention. They are not included in the management system of the government and social organizations, and rarely appear in the field of vision of scholars and journalists. To some extent, this is a neglected and forgotten group.