Abstract
Geographical variation in social relationships among five races of the dark-eyed junco (Junco hyemalis L.) was examined by observing interactions in racially mixed flocks. Interactions were observed at nine sites in Colorado and South Dakota during two winters. Interactions between each pair of junco races were typically dominated by the same race at all sites. However, the percentage of interactions won by each race varied significantly between certain sites. Computer simulations of winter site occupancy by hypothetical junco populations were used to examine the ability of small site population sizes to generate variation in inter-racial dominance relationships among sites. These simulations revealed that racial dominance should vary more among sites when site populations are small, and when races are relatively equal in dominance. Additional simulations revealed that the dominance relationships observed at field sites in this study are unlikely to have arisen from races selecting sites randomly; consequently, nonrandom site occupation appears to be occurring. Patterns of variation in racial dominance appear not to have been produced by dominant races excluding subordinates from
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call