Female preference for long tails was first observed in long-tailed widowbirds, and then subsequently observed in Jackson's widowbird and the red-collared widowbird. Tail length explains 47% of the male's reproductive success, indicating the strength of this sexual ornament. Tail symmetry, however, does not have an effect on mating success. In the red-collared widowbird there is a strong trade-off between carotenoid coloration, which is an agonistic signal and tail length, which is an epigamic signal, directly attracting females. These are both costly ornaments that are maintained through multiple receivers.