Bowers on the savanna: display courts and mate choice in a lekking widowbird

Individual display courts, constructed by lekking male Jackson'swidowbirds, Euplectes jacksoni, were studied with respect tofemale mate choice. The court is a shaped tuft of grass, surroundedby a circular track on which displays and mating are performed.At the base of the tuft there are two cup-shaped recesses. Femalessit in front of, and often pluck at, one ofthese recesses whilemales display at the opposite side for about 1 min before theyapproach and attempt to copulate. The vast majority of femalesvisiting courts with experimentally destroyed or impaired recessesstayed shorter than the average time of male approach, whereasvisits to improved courts lasted longer than visits to intactcourts. All recorded copulations occurred at intact or improvedcourts. The display court is a weak predictor of male matingsuccess compared to other choice cues such as display rate andtail length, but females may require the court quality to exceeda certain stimulus threshold to accept the male. Court qualitycorrelates positively with male lek attendance and tail length.This paper discusses the implications of the results for sexualselection and considers the possibility that display courtsare ‘external sexual ornaments.’ From comparativedata on breeding behavior in related species, the display courtand its associated behaviors are suggested to originate frommale nest-initiation and female nest-inspection within an ancestralstate of resource-defense polygyny.