Seeing Red

Taken June 12, 2005 at Boggs Lake Preserve in Lake Co., California, this photo shows the lowest bloom beginning to take on red coloration after pollination. What function does this red phase serve? Why not stay yellow or turn brown? If Grant’s Floral Syndromes hold true and bees favor yellow flowers, does this shift to red after pollination encourage bees to visit the yellow and as yet unpollinated flowers?