A REANALYSIS OF PATAS MONKEYS GRIMACE AND GECKER DISPLAY AND A DISCUSSION OF THEIR LACK OF FORMAL DOMINANCE

In a captive group of subjects, we tested the claim (Jacobus and Loy, 1981) that patas monkeys possess a ''grimace and gecker'' display that functions as a signal of submission/appeasement. The results show the grimace and gecker to be an ineffective preventive both for supplanta tion and for the continuation of aggression by dominant animals, which suggests that it is not an important display for patas monkeys. Witho ut the grimace and gecker, it appears chat patas monkeys lack ''formal dominance.'' Therefore, we investigated the effects of such a deficie ncy via interspecific comparisons. They suggest that patas monkeys do not differ from cercopithecine species that possess formal dominance w ith regard to frequency of fighting, intensity of fighting, or rates o f postfight reconciliation. Patas show lower races of allogrooming and higher fight:groom ratios than formal dominance species do. These res ults support the view that a lack of formal dominance is likely to be correlated with reduced social cohesion.