SIGNALS IN INTRA-SEXUAL COMPETITION BETWEEN RING-NECKED PHEASANT MALES

Many sexual ornaments are signals commonly used in both sexual selecti on contexts: mate choice and intra-sexual competition. Previous studie s show that female choice in ring-necked pheasants, Phasianus colchicu s, is influenced by features of some male ornaments. Experiments and c orrelational data were used in this study to investigate the role of m ale ornaments in male-male agonistic encounters. Some traits used by f emales in mate choice, namely tail length and black points in the watt le, had no effect in male-male competition, but the length of ear tuft s had a role in both contexts. The most important traits appeared to b e the head ornaments, which include ear tufts, but also wattle size. H ead ornaments function as coverable signals that are displayed to riva l males informing about readiness to fight, fighting ability and resou rce-holding power; and the total time spent displaying correlated with testosterone level, physical condition and rank. Thus, the costs of d isplaying head ornaments appear to be both inherent and target-receive r dependent. (C) 1997 The Association for the Study of Animal Behaviou r.