Pollinator preferences and their potential effects on floral trait diversity

The Rocky Mountain columbine, Aquilegia coerulea, is a perennial plant found in mountainous areas in the western U.S.. The two major pollinators of this plant species are bumblebees and hawkmoths. The purpose of the current study was to examine preferences of the two major pollinators for specific flower traits which included  flower color, flower size, spur length and pollen production. First, we hypothesize that both pollinators  prefer larger over smaller flowers. Secondly, we expect that bumblebees prefer blue flowers while the whitelined sphinx moth, Hyles lineata, prefers white flowers during the evening but have no color preference during the day. Thirdly, that hawkmoths should prefer flowers with longer spurs while bumble bees are not affected by spur length. Finally, we hypothesize that bumblebees prefer flowers with a larger pollen reward while hawkmoths are not influenced by pollen reward. Choice assays to determine pollinator preference for specific floral traits were performed using both real and artificial flowers.