Optical Illusion

On the ride home through western Loudon County, Virginia, yesterday afternoon, my attention was drawn to a crow sitting on the grassy roadside right-of-way flicking its wings. The next thing I noticed was a very large white patch on the dorsal surface of one wing. But I quickly realized that it was merely an illusion created by the glint of the sun off the bird's feathers, a fleeting trick that my eyes had played on me before under certain lighting conditions. It's amazing how something black can actually appear to be white, if only for a moment.