is determined by the rank of his family. Although dominance is determined differently in each case, it is influenced by the relationships between members of social groups. Regulation mechanisms Individuals with greater hierarchical status tend to displace those ranked lower from access to space, to food and to mating opportunities. Thus, individuals with higher social status tend to have greater reproductive success by mating more often and having more resources to invest in the survival of offspring. Hence, hierarchy serves as an intrinsic factor for population control, ensuring adequate resources for the dominant individuals and thus preventing widespread starvation. Territorial behavior enhances this effect. In eusocial animals The suppression of reproduction by dominant individuals is the most common mechanism that maintains the hierarchy. In eusocial mammals this is mainly achieved by aggressive interactions between the potential reproductive females. In eusocial insects, aggressive interactions are common determinants of reproductive status, such as in the bumblebee Bombus bifarius, the paper wasp Polistes annularis and in the ants Dinoponera australis and D. quadriceps. In general, aggressive interactions are ritualistic and involve antennation (drumming), abdomen curling and very rarely mandible bouts and stinging. The winner of the interaction may walk over the subordinated, that in turn assumes a prostrated posture. To be effective, these regulatory mechanisms must include traits that make an individual rank position readily recognizable by its nestmates. The composition of the lipid layer on the cuticle of social insects is the clue used by nestmates to recognize each other in the colony, and to discover each insect's reproductive status (and rank). Visual cues may also transmit the same information. Paper wasps Polistes dominulus have individual "facial badges" that permit them to recognize each other and to identify the status of each individual. Individuals whose badges were modified by painting were aggressively treated by their nestmates; this makes advertising a false ranking status costly, and may help to suppress such advertising. Other behaviors are involved in maintaining reproductive status in social insects. The removal of a thoracic sclerite in Diacamma ants inhibits ovary development; the only reproductive individual of this naturally queenless genus is the one that retains its sclerite intact. This individual is called a gamergate, and is responsible for mutilating all the newly emerged females, to maintain its social status. Gamergates of Harpegnathos saltator arise from aggressive interactions, forming a hierarchy of potential reproductives. In the honey bee Apis mellifera,