Light Absorption in the Bee Photoreceptor

Abstract

Photodetection by the individual rhabdomeres of the worker-bee photoreceptor (rhabdom) is analyzed by use of electromagnetic theory. The analysis takes full account of the rhabdom’s anisotropic absorption properties. We find, by coupled-mode theory, that only certain modes of a lossless symmetric rhabdom are stable on the lossy rhabdom. Furthermore, the fine structure of the rhabdom (a) enhances the detection of certain modes, whereas it discriminates against others, (b) acts as a polarization detection mechanism, and (c) provides information about the direction of incoming light.