They are intelligent, vulnerable young people who work hard for low pay and tend to live together in poor-quality housing. Little wonder, then, that a Beijing-based academic termed them 'the ant tribe'.
Professor Lian Si, of the University of International Business and Economics, headed a team that surveyed 4,807 such ants in seven mainland cities. Their number has grown to more than 1 million - with 150,000 each in Beijing, Shanghai and Guangzhou and more than 100,000 in various second-tier cities such as Wuhan, Hubei .
The results: ants view mainland society as insecure and unjust, with their personal safety also threatened, but migr-'ants' in their 20s with university degrees hold high expectations of being able to trade up to a decent life in a couple of years.
About one-third of those surveyed graduated from China's top universities, such as Peking, Tsinghua and Fudan.
'This figure shocked us,' said Lian, who recorded the survey results in his book Ant Tribe II - Whose Era?, which has yet to be released.
These young people live in various kinds of housing, ranging from farmer-built yards in suburban Beijing to villages inside cities such as Guangzhou and Wuhan, and 'high-density' flats (with several roommates) in Shanghai. According to Lian, their average living space is about five square metres, their average monthly income is 1,903 yuan (HK$2,217), and more than 80 per cent are from rural families.