Mating success is dependent on a variety of factors that range from the plumage exhibited by a male to the composition of the lek itself. In one study, the female Guianan cocks-of-the-rock displayed sexual selection based on sequential comparisons or threshold standards. The hens engaged in a “pool–comparison” tactic, meaning that females chose males of higher rank in courtship. Males of higher rank were those with more matings received from other females; the lower-ranking single males were ignored. The rankings were determined by where the courts were positioned in the lek: courts that were more centrally placed indicated more successful and higher-ranking males. The females in the study were individually observed to aggregate towards larger, more centrally concentrated leks, demonstrating active female choice.