Ultraviolet divergence short distances. The name comes from the earliest example of such a divergence, the "ultraviolet catastrophe" first encountered in understanding blackbody radiation. According to classical physics at the end of the nineteenth century, the quantity of radiation in the form of light released at any specific wavelength should increase with decreasing wavelength—in particular, there should be considerably more ultraviolet light released from a blackbody radiator than infrared light. Measurements showed the opposite, with maximal energy released at intermediate wavelengths, suggesting a failure of classical mechanics. This problem eventually led to the development of quantum mechanics. The successful resolution of the
Ultraviolet communication in butterflies some species this distinction is not seen at all times, and UV patterns may vary visually depending on the position of reflecting light. This can be seen in the common brimstone, where males will exhibit male or female patterns of iridescence with different positions, distances, and angles of light - this is known as the "gynandromorphic" effect. The ultraviolet communication system employed by butterflies is also used an indicator of male sex to other rival males in the butterfly, "Colias eurytheme". In this species, only males are able to reflect ultraviolet light off the dorsal side of their wings, while