perch and watches the world while flicking his long, bifurcated tongue, unperturbed by his audience. With such bright hues and astonishing aerial abilities, it’s no wonder hummingbirds seem bold in more ways than one.
A Flash of Color A major feature of hummingbird plumage is the shifting, shimmering colors of crests, gorgets (a patch on the throat), and other feather structures. And the composition of those structures is both intricate and impressive. A feather consists of many tiny subfeathers, called barbs, and the barbs are made up of another layer called barbules. Some colors on a hummingbird’s feathers are created by melanin pigments, but the iridescence is caused by the structure of the stacked platelets in the feather barbules and how they reflect light. These platelets are only up to 18 microns thick. About one third of the feather is modified for iridescence; the overlapping arrangement of feathers creates the unbroken shimmer. As the bird moves or changes position, different lightwaves are reflected, making hummingbird watching a kaleidoscopic experience.
A Tropical Treasure Beyond the beak: When fully extended, a hummingbird’s tongue can be twice as long as its bill.
By hummingbird standards, white-necked jacobins are large, measuring about four inches long. Adult males have a brilliant blue head and chest, while females are mostly green. Inhabiting the humid forests in southern Mexico through Central America to Colombia and the Amazon and Orinoco basins, white-necked jacobins tend to feed mostly in the forest can-