Prior - residence and coat - tail effects in dominance relationships of male dark - eyed

Captive male dark-eyed juncos from two different aviaries were combined either in one group's original aviary (seven replicates) or in a third aviary (two replicates). These experiments controlled for effects of handling the subjects during transfers between aviaries and, in statistical analysis of the results, took into account constraints on the dominance relationships within combined groups. The results (l) confirmed the influence on dominance of prior residence in an aviary and (2) revealed a lack of independence in the dominance relationships between individuals from different original groups. This lack of independence probably resulted from an influence ofdominant individuals on the relationships oftheir lamiliar subordinates, a'coat-tail' eflect. (3) The results further indicated that previous experience with dominance or recognition ofprevious opponents outweighed the effect ofprior residence. Consequently, prior residence might represent a last resort in the settlement ofcontests in this species, as predicted on theoretical grounds for the use of conventional asymmetries in the settlement of contests. The coat-tail effect, if it applies in the field, would create an advantage for subordinates associating with lamiliar