1. Archaeology: It is a subject involving a wide range of fields. China's investment in archaeological research is increasing year by year, but the enrollment quota is small.
2. Silkworm science: it is a professional science about the study of silkworm species, living habits and life activities, and it is rarely favored by people.
3. Paleontology: The professional requirements for the candidates themselves are relatively high, which is affected by market employment, so the number of professional enrollment is limited.