Co-option, homosocial
Homosocial co-option refers to the mechanism whereby members are added to the existing group of people in committees or other personal associations according to the principle of similarity. Only those people are given access to influential positions who are as similar as possible to the people already in these positions, e.g. who have the same gender or a similar educational background.
Source: Glossar im Handbuch zur Gleichstellungspolitik an Hochschulen