A new kind of neural superposition eye: the compound eye of male Bibionidae


IN neural superposition eyes the signals of receptors pointing to one region in space are neurally pooled. The optical and neural organisation of these eyes yields an enhanced absolute light sensitivity while minimising the loss of visual acuity that accompanies pooling. In the compound eyes of flies (Diptera), this is achieved in the following way. The distal endings of seven retinula cells lie near the back focal plane of each lens1. Their light-sensitive structures, the rhabdomeres, are optically isolated from each other. The rhabdomeres of one ommatidium have different optical axes. The optical axes of seven rhabdomeres in seven adjacent ommatidia are parallel (Fig. 1a, ref. 2). The axons of such retinula cells (except the central ones, which pass through to the second optic ganglion) converge onto the same cartridge of secondary neurones in the first optic ganglion, the lamina3,4. Thus, each lamina cartridge ‘looks at’ one point in space. In one suborder of flies (Cyclorrhapha), to which the housefly Musca and the fruitfly Drosophila belong, the arrangement of rhabdomeres is asymmetrical (Fig. 1a). Eyes organised in this way are one form of neural superposition eyes2. Here, I provide evidence that a different kind of neural super-position eye exists in the Bibionidae, a family of flies of the suborder Nematocera. Bibionids are peculiar in being extremely sexually dimorphic in their visual system: the males have, in addition to small ‘female’ eyes, a pair of large dorsal compound eyes, functionally correlated presumably with the male habit of swarming and chasing females. These dorsal eyes differ from the eyes described in more advanced flies in two respects: the rhabdomeres are symmetrically arranged and the rhabdomeres with parallel optical axes are found in ommatidia √3 times further apart than adjacent ommatidia. The course of the retinula cell axons in the lamina differs accordingly.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    Kirschfeld, K. & Franceschini, N. Kybernetik 5, 47–52 (1968).

  2. 2

    Kirschfeld, K. Expl Brain Res. 3, 248–270 (1967).

  3. 3

    Trujillo-Cenóz, O. & Melamed, J. J. ultrastruct. Res. 16, 395–398 (1966).

  4. 4

    Braitenberg, V. Expl Brain Res. 3, 271–298 (1967).

  5. 5

    Franceschini, N. & Kirschfeld, K. Kybernetik 8, 1–13 (1971).

  6. 6

    Strausfeld, N. J. Atlas of an Insect Brain (Springer, Berlin, 1976).

  7. 7

    Franceschini, N. & Kirschfeld, K. Kybernetik 9, 159–182 (1971).

  8. 8

    Pick, B., Biol. Cybernetics 26, 215–224 (1977).

  9. 9

    Dietrich, W. Z. wiss. Zool. 92, 465–539 (1909).

  10. 10

    Grenacher, H. Untersuchungen über das Sehorgan der Arthropoden, insbesondere der Spinnen, Insecten und Crustaceen (Vandenhoek and Ruprecht, Göttingen, 1879).

  11. 11

    Ioannides, A. C. & Horridge, G. A. Proc. R. Soc. Lond. B190, 373–391 (1975).

Download references

Author information



Rights and permissions

Reprints and Permissions

About this article

Cite this article

ZEIL, J. A new kind of neural superposition eye: the compound eye of male Bibionidae. Nature 278, 249–250 (1979). https://doi.org/10.1038/278249a0

Download citation

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.