A Hummingbird’s Shining Armor
The gorget is just a small part of the fireworks display.
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When a perched male Ruby-throated Hummingbird raises its head toward the sun at just the right angle, its throat glitters like a crimson spotlight. When it turns its head slightly, the birds throat no longer gleams. It appears colorless, dark.
A hummingbirds brilliant throat feathers are called its gorget (pronounced gor-jit). The term comes from days of old, when a knight-in-armor wore a metallic collaror gorgetto protect his throat. The hummingbirds intense glint is the result of iridescence, rather than colored pigments. The birds throat feathers contain minutely thin, film-like layers of platelets, set like tiles in a mosaic against a darker background. Light waves reflect and refract off the mosaic, creating color in the manner of sun glinting off oily film on water.
"There he goes! Diving in display toward the female. He plunges downward al-most vertically, achieving tremendous speed. Then, he levels off and heads straight into the sun, which makes his gorget glow with iridescent brilliance." (The quote is from Alexander F. Skutch and Arthur B. Singer's The Life of the Hummingbird.)
See the Rufous Hummingbird's gorget at .
Hummingbird sounds provided by at the , Ithaca, New York. Ruby-throated Hummingbird recorded by R.S. Little. Annas Hummingbird recorded by T.G. Sander.
Annas Hummingbird display chirp recorded by C. Clark and A. Varma, U.C. Berkeley. Ambient track recorded by Kessler Productions. BirdNote's theme music was composed and played by Nancy Rumbel and produced by John Kessler.
Producer: John Kessler
Executive Producer: Chris Peterson / Dominic Black
Written by Bob Sundstrom
穢 2015 Tune In to Nature.org March 2015 Narrator: Mary McCann