Nobody knows for sure, but we do know how the queen does it. She harrasses all females and puts them under constant stress. They actually don t ovulate. When a new male tries to mate with her, she often tries to kill him. Stan speculates that the male strategy could be to try it once.
Genetic analyses are forthcoming, but research is still in the beginning.
Colonies with more than one queen have been observed. One had a queen and her daughter, who also bred. The mole-rats do not recognize individuals by smell or some such. When you introduce foreigners into a colony, they are readily accepted. When two colonies expand into each other s area, the animals will fight fiercely though, sometimes taking slaves.