Adult males mark territories with urine and with a scent gland located on the front of the throat. Territorial confrontations between two troops may involve growling, scent marking, and ritualistic leaping toward the enemy territory but not direct physical contact. During the breeding season, however, there are fights and sometimes serious injuries. The dominance hierarchy that existed in the nonmating season may change. A formerly subordinate male may take over his own group or leave his group and attain dominant status in another group.
Females permit mating only by males that retain or achieve dominance during the mating season.
The overall mating season extends from January to March. There is a single young. The IUCN designates P. diadema as vulnerable. Only a few hundred individuals are thought to survive, and their range is contracting because of savannah fire encroachment. Populations of P. verreauxi also have been greatly reduced and have become split up by human habitat destruction.