Male White-Necked Jacobin Hummingbird (Florisuga mellivora). Flores, Guápiles, Costa Rica

I can honestly say that the hummingbirds of Costa Rica are the most beautiful birds I have ever seen and I will share them with you in this post. Hummingbirds are from the New World and constitute the family Trochilidae. They are some of the smallest birds in the world and have the greatest metabolism of any animal. To keep energy when food is limited, and nightly when not foraging, they go into dormancy, a state similar to hibernation, slowing metabolic rate to 1/15th of its normal rate. They are known as hummingbirds because of the humming sound generated by their whipping wings which wave at high frequencies audible to humans. They flutter in mid-air at rapid wing-flapping rates, typically around 70 to 80 times per second, allowing them also to fly at speeds exceeding 34 miles per hour. Hummingbirds fall into nine main groups or clades, the Topazes and Jacobians, Hermits, Mangoes, Brilliants, Coquettes, the giant hummingbird Patagona, Mountain Gems, Bees, and Emeralds as established by DNA evidence. These clades also define their relationship to nectar-bearing flowering plants and the birds’ continued spread into new geographic areas. The brilliant, iridescent colors of hummingbird plumage are caused by the refraction of incident light by the structures of certain feathers. Like any diffraction grating or prism, these structures split light into its component colors, and only certain frequencies are then refracted back to your eyes. Thus, you have to be in a particular location with respect to the light and hummingbird to see the bright colors of the head and neck or gorget. I have arranged the hummingbirds in this post roughly by elevation with the highest elevations first and the lowest elevations last.
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