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Studies have shown greater avian migration distances associated with longer, more pointed wings with greater aspect ratio, reduced body mass, and less wing loading. However, until recently the selection effects of breeding elevation on flight morphology have been studied much less extensively, and mainly in hummingbirds. No previous study has evaluated, within a single avian taxon, the selection effects of both breeding elevation and migration distance on flight morphology. The Orange-crowned Warbler, Leiothlypis celata, is a North American passerine with 4 subspecies tending to have significantly different mean breeding elevations and migration distances. Comparison of paired means showed that the subspecies with the highest mean breeding elevation, L. c. orestera, had significantly longer wings, lower body mass, and lower wing loading than did L. c. celata, the subspecies with the longest mean migration distance. Aspect ratio and wing pointedness were not significantly different between the subspecies. These results suggest that breeding elevation was more meaningful in shaping flight morphology in the species than was migration distance. Principal components modeling and Type 3 analyses for all 4 subspecies showed that both breeding elevation and migration distance had a significant relationship with principal component 1, and thus a significant selection effect on flight morphology. The P values based on analyzing just 3 rather than 4 subspecies, and excluding L. c, sordida, which had both the lowest breeding elevation and shortest migration distance, was highly statistically significant for the relationship of factor 1 and breeding elevation, but not quite significant for factor 1 and migration distance. Plotting breeding elevations against principal component 1, for both 4 and 3 subspecies, produced trend lines that were steep, evidence of strong relationships. Plotting migration distances against factor 1 produced trend lines that were essentially level, showing little or no relationship. Results of this and several other recent studies have shown that many birds existing at higher elevations have less body mass and longer wings than similar birds existing at lower elevations. These findings are remarkably similar to recent findings for the selection effects of climate change, which also show a shift to birds with less body mass and longer wings. The selection effects of both breeding elevations and migration distances will need to be accounted for in future studies into the selection effects of climate change.