Journal of Comparative Physiology A

, Volume 158, Issue 2, pp 165–177

Spectral sensitivity of photoreceptors in insect compound eyes: Comparison of species and methods

  • R. Menzel
  • D. F. Ventura
  • H. Hertel
  • J. M. de Souza
  • U. Greggers
Article

DOI: 10.1007/BF01338560

Cite this article as:
Menzel, R., Ventura, D.F., Hertel, H. et al. J. Comp. Physiol. (1986) 158: 165. doi:10.1007/BF01338560

Summary

Three different methods were used to determine the spectral sensitivity of retinula cells in the compound eyes of three species of hymenopteran insects (Apis mellifera, Melipona quadrifasciata, Osmia rufa). The conventional flash method gives the least reliable results. Sensitivity is extremely sensitive to small fluctuations of the resting potential and long lasting changes induced by preceding test flashes. The ramp method, which speeds up a spectral scan to about 1 min and keeps effective illumination constant at every flash, determines S(λ) much more reliably. The best results are obtained with the spectral scan method, which provides the experimenter with aS(λ) function of high spectral resolution within 20 s. Using this method we demonstrate that the high observed variability inS(λ) of individual receptors is the result of the inadequacy of the flash method, which was the only method used in earlier studies.

Double microelectrode experiments and variations of the stimulus conditions reveal that field potentials and return flow of electric current produced by activated neighboring cells have no effect in the bee eye. We conclude that the model of Shaw (1975, 1981) of current flow in the locust and fly eye does not apply to the bee eye. Very rare recordings (about 1%) of UV receptors with hyperpolarizing responses to long wavelength light are interpreted as having a synaptic inhibitory connection to green receptors.

The improvement of spectral measurements of single receptors allows us for the first time to model the spectral input to a color-coding network with great precision.

Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • R. Menzel
    • 1
  • D. F. Ventura
    • 2
  • H. Hertel
    • 1
  • J. M. de Souza
    • 2
  • U. Greggers
    • 1
  1. 1.Institut für Tierphysiologie NeurobiologieFreie Universität BerlinBerlin 33Germany
  2. 2.Instituto de PsicologiaUniversidade de São PauloSão PauloBrazil

Personalised recommendations