Interacting effects of lek placement, display behavior, ambient light, and color patterns in three neotropical forest-dwelling birds

Forests exhibit a mosaic of different spectral environments that arise from forest geometry and weather. If visual signals are used in mate choice, then forest geometry and weather will affect reproductive behavior because the appearance of a visual signal depends on the joint effects of ambient light and the animal's reflectance spectra. We investigated three lekking birds at Nourages field station, French Guiana: Rupicola rupicola, Corapipo gutturalis, and Lepidothrix serena. Conspicuousness is a function of ambient light spectra during displays and the reflectance spectra of color pattern elements of the birds and their visual backgrounds. Each species places its lek and performs its lek displays in only one or two of the available light environments, and some may specialize in the more extreme spectra even within each light environment. The color patterns and behavior of each species maximize its visual contrast during its display and reduce it off the lek or on the lek but not displaying. Each species does this with a different combination of colors and light environments. If this phenomenon is general, then it has important implications for the evolution of color patterns and display behavior.