Robert Hooke, the man who coined the term “cell” to describe biological cells, was also one of the early investigators of structural color, the creation of color in nature due to nano-structures that cause interference among light waves. Rather than pigments, structural colors often occur in what would otherwise be colorless substances. Hooke noted this in Observ. XXXVI in Micrographia, explaining that when he placed the iridescent feathers under water and looked at them through the microscope, the coloring vanished, the water, he suspected, essentially filled in the gaps between his theorized nano-structures, and, having a “greater congruity to Feathers than the Air,” the water becomes the new reflective surface, no longer providing the scattered refraction he thought caused structural colors.
Hooke studied peacock feathers, but also the much more common feathers of ducks. One of the striking thing about dicks is the flash of color often hidden in their wings, and often the beautiful iridescent purples and greens on the males‘ heads. On a recent morning visit to the Hornsby Bend Bird Observatory, I was able to see some of these structural colors amid the annual migration of ducks and other water fowl. The striking wing patches of the Blue-Winged Teal, the stunning head design on the Green-Winged Teal, and the green-black of the Northern Shoveler, changing depending upon the direction of the sunlight.
Not to be outdone, of course, the perching birds (Passeriformes) gave a subtle (and not so subtle) display of color and call to liven up the shoreline.
Hooke studied peacock feathers, but also the much more common feathers of ducks. One of the striking thing about dicks is the flash of color often hidden in their wings, and often the beautiful iridescent purples and greens on the males‘ heads. On a recent morning visit to the Hornsby Bend Bird Observatory, I was able to see some of these structural colors amid the annual migration of ducks and other water fowl. The striking wing patches of the Blue-Winged Teal, the stunning head design on the Green-Winged Teal, and the green-black of the Northern Shoveler, changing depending upon the direction of the sunlight.
Not to be outdone, of course, the perching birds (Passeriformes) gave a subtle (and not so subtle) display of color and call to liven up the shoreline.