Floral colors in the high arctic with reference to insect–flower relations and pollination

Abstract

Some review, concepts, terminology, and methods are given towards the description of colors, here, of flowers of the high arctic flora of the Canadian Arctic Archipelago, in the insect (including ultraviolet) and human visual spectra. Photographs and spectral reflection curves are given. The various flower colors found elsewhere do not occur in the same proportions in the high arctic where white and yellow predominate. Ultraviolet is reflected from several yellow (insect-red) flowers, making them insect-purple. Patterns and markings in the ultraviolet or other colors may be simple or complex, but cannot be described as honey-guides. To insects, the high arctic flowers of the different species have more distinctive colors and color patterns, and there are more different colors and color patterns, than there are to humans. Most flowers have greater luminance factors than do their backgrounds so stand out as different in color and brightness. Yellow flowers (with or without ultraviolet) are the most attractive to insects; other colored flowers are visited by special groups of insects or when yellow flowers are not available, or both. Color alone cannot account for the attractiveness or unattractiveness of some blooms. Some flower visitors are found in flowers in which they would be least conspicuous, and cryptic color changes may operate in the high arctic crab spider.