Electrophysiological responses in mutant-eyed drones of Apis mellifera to selected wavelengths of light

Abstract

The neural responses of eyes of wild-type and seven mutant-eyed drones of Apis mellifera to wavelengths of light between 350 and 700 nm was determined. The responses of all types were identical in young drones (1–3 days after emergence), with maximum sensitivity at 440 nm. No change in the wavelength of maximal sensitivity occurred in the wild-type drones, in the brick mutant, or in three permanently white-eyed mutants, as ageing continued. In two mutants a shift of 40 nm toward the longer wavelengths occurred as ommochrome synthesis proceeded during the first 10 to 12 days of adulthood. It is suggested that binding of the ommochrome with the proteins of the pigment cells alters the quality of light reaching the underlying visual pigment. In the third mutant, a shift of similar magnitude occurred with accumulation of ommochrome precursor. A hypothesis that this material filters the entering light, and hence shifts the response maximum agrees well with the observations obtained.