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Apostatic selection by blue jays produces balanced polymorphism in virtual prey

Abstract

Apostatic selection, in which predators overlook rare prey types while consuming an excess of abundant ones, has been assumed to contribute to the maintenance of prey polymorphisms1,2,3. Such an effect requires predators to respond to changes in the relative abundance of prey, switching to alternatives when a focal prey type becomes less common4,5. Apostatic selection has often been investigated using fixed relative proportions of prey1,6, but its effects on predator–prey dynamics have been difficult to demonstrate7. Here we report results from a new technique that incorporates computer-generated displays8,9 into an established experimental system, that of blue jays (Cyanocitta cristata) hunting for cryptic Catocala moths10. Digital prey images from a virtual population are presented to predators. The relative numbers that escape detection determine the subsequent abundance of each prey type. If apostatic selection does promote stability, the system should converge on an eqlibrium in which each prey type appears at a characteristic abundance. Our results show that the detection of cryptic prey does involve apostatic selection, and that such selection can function to maintain prey polymorphism.

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Figure 1: The five types of digital moths used in these experiments (moth 1 to moth 5, from left to right), presented against backgrounds of three levels of crypticity to illustrate the difficulty of the detection task.
Figure 2: Population numbers and prey detectability of three prey morphs in three successive replications of the virtual prey procedure.
Figure 3: Functional response curves for the three morphs in the first three replications.
Figure 4: Population numbers of four morphs in the last two replications of the virtual predation procedure.

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References

  1. Allen, J. A. Frequency-dependent selection by predators. Phil. Trans. R. Soc. Lond. B 319, 485–503 (1988).

    Article  ADS  CAS  Google Scholar 

  2. Clarke, B. C. in Taxonomy and Geography (ed. Nichols, D.) 47–70 (Systematics Association, Oxford, 1962).

    Google Scholar 

  3. Clarke, B. C. The evidence for apostatic selection. Heredity 24, 347–352 (1969).

    Article  CAS  Google Scholar 

  4. Murdoch, W. W. Switching in general predators: experiments on predator specificity and stability of prey populations. Ecol. Monogr. 39, 335–354 (1969).

    Article  Google Scholar 

  5. Murdoch, W. W. & Oaten, A. Predation and population stability. Adv. Ecol. Res. 9, 1–131 (1974).

    Google Scholar 

  6. Cooper, J. M. Apostatic selection on prey that match the background. Biol. J. Linn. Soc. 23, 221–228 (1984).

    Article  Google Scholar 

  7. Cooper, J. M. & Allen, J. A. Selection by wild birds on artificial dimorphic prey on varied backgrounds. Biol. J. Linn. Soc. 51, 433–446 (1994).

    Article  Google Scholar 

  8. Glanville, P. W. & Allen, J. A. Protective polymorphism in populations of computer-simulated moth-like prey. Oikos 80, 565–571 (1997).

    Article  Google Scholar 

  9. Plaisted, K. C. & Mackintosh, N. J. Visual search for cryptic stimuli in pigeons: implications for the search image and search rate hypotheses. Anim. Behav. 50, 1219–1232 (1995).

    Article  Google Scholar 

  10. Pietrewicz, A. T. & Kamil, A. C. Search image formation in the blue jay (Cyanocitta cristata). Science 204, 1332–1333 (1979).

    Article  ADS  CAS  Google Scholar 

  11. Sargent, T. D. Legion of Night: The Underwing Moths (Univ. Massachusetts Press, Amherst, 1976).

    Google Scholar 

  12. Endler, J. A. Progressive background matching in moths, and a quantitative measure of crypsis. Biol. J. Linn. Soc. 22, 187–231 (1984).

    Article  Google Scholar 

  13. Holling, C. S. The functional response of predators to prey density and its role in mimicry and population regulation. Mem. Entomol. Soc. Can. 45, 1–60 (1965).

    Google Scholar 

  14. Tinbergen, N. The natural control of insects of pinewoods I. Factors influencing the intensity of predation by songbirds. Arch. Néerland. Zool. 13, 265–343 (1960).

    Article  Google Scholar 

  15. Bond, A. B. Visual search and selection of natural stimuli in the pigeon: the attention threshold hypothesis. J. Exp. Psychol. Anim. Behav. Process. 9, 292–306 (1983).

    Article  CAS  Google Scholar 

  16. Blough, P. M. Selective attention and search images in pigeons. J. Exp. Psychol. Anim. Behav. Process. 17, 292–298 (1991).

    Article  CAS  Google Scholar 

  17. Langley, C. M. Search images: selective attention to specific visual features. J. Exp. Psychol. Anim. Behav. Process. 22, 152–163 (1996).

    Article  CAS  Google Scholar 

  18. Wallace, B. Basic Population Genetics 229–230 (Columbia Univ. Press, New York, 1981).

    Google Scholar 

Download references

Acknowledgements

We thank K. Cheng, J. Endler, A. Joern, S. Shettleworth, A. Zera, W. Wagner, J. Allen and J. Diamond for comments and suggestions. This research was supported by a grant from The National Science Foundation.

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Correspondence to Alan B. Bond.

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Bond, A., Kamil, A. Apostatic selection by blue jays produces balanced polymorphism in virtual prey. Nature 395, 594–596 (1998). https://doi.org/10.1038/26961

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