The color on the throat, or gorget, and head of a male is particularly spectacular. The platelets on these feathers are like flat mirrors, and light reflects in only one direction. This is why the gorget of a male ruby-throat, for instance, dazzles in sunlight but may look black in shade. Hummingbirds know this. By carefully adjusting his position in relation to the observer and the sun, a male purposely flashes his colors to intimidate a rival or attract a mate.
