The Hima people are a nomadic ethnic group from Ethiopia, who migrated from the Nile region to areas of Uganda, Rwanda, and Burundi in the early centuries AD. They lead a transient lifestyle, relying on their cattle for sustenance. The Hima's way of life is unique, with their small grass huts designed for easy disassembly and relocation as they move.

The Hima practice intra-tribal marriage customs, which are quite distinct. Fathers and sons share a wife, as women are regarded as family assets rather than individual property. The bride's dowry consists of eight heifers and one bull, provided by the groom's father. After marriage, the bride does not partake in labor and is even prohibited from tending to the fences to prevent the cattle from being harmed. The Hima's fertility cycle is remarkably regular, with women giving birth to a child only every five years, which has piqued the interest of anthropologists. Whether this is due to natural contraceptive methods or a genetic adaptation to their nomadic lifestyle remains to be thoroughly investigated by scientists.

The Hima's reproductive patterns are not only a mystery but may also hold potential breakthroughs for the field of reproductive science.