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Oecologia

, Volume 64, Issue 3, pp 287–294 | Cite as

Partial preference of insects for the male flowers of an annual herb

  • G. Bell
  • L. Lefebvre
  • L. -A. Giraldeau
  • D. Weary
Original Papers

Summary

The flowers of the annual herb Impatiens capensis have distinct male and female phases. The male phase lasts four times as long as the female phase, and male flowers contain about 50% more nectar than female flowers. This suggests that the bulk of allocation to the flower is designed to ensure the dispersal of pollen rather than the fertilization of ovules. Honeybees, wasps and bumble bees all land on male flowers more often than would be expected by chance, and, having landed, wasps and bumble bees are more likely to enter a male flower than a female flower. The frequency of male flowers in the diet therefore exceeds their frequency in the population. This preference, although strong and consistent, is only partial, since some female flowers are included in the diet. We propose two hypotheses to account for the observed partial preference, the first based on competition between bees for flowers, and the second asserting that the bees detect nectar levels directly without using floral gender as a cue. The results of an experiment in which the most obvious gender cue, the androecium, was removed are consistent with the second hypothesis.

Keywords

Female Flower Male Flower Annual Herb Partial Preference Male Phase 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Charnov EL (1973) Optimal foraging: some theoretical explorations. Ph.D. Thesis, University of Washington, SeattleGoogle Scholar
  2. Charnov EL (1976) Optimal foraging: the marginal value theorem. Theoret Pop Biol 9:129–136Google Scholar
  3. Cruden RW, Hermann MH, Peterson S (1983) Patterns of nectar production and plant-pollinator coevolution. In: Bentley B, Elias T (eds), The Biology of Nectaries. Columbia Univ Press, NY, pp 80–125Google Scholar
  4. Fretwell SD (1972) Populations in a Seasonal Environment. Princeton University Press, Princeton, New JerseyGoogle Scholar
  5. Heinrich B (1972) Energetics of temperature regulation and foraging in a bumblebee, Bombus terricola Kirby. J Comp Physiol 77:49–64Google Scholar
  6. Heinrich B (1976) Resource partitioning among some eusocial insects: bumblebees. Ecology 57:874–889Google Scholar
  7. Heinrich B (1978) Bumble Bee Economics. Harvard University Press. Cambridge, MassachusettsGoogle Scholar
  8. Josselyn J (1972) New-Englands Rarities Discovered. G. Widdowes, LondonGoogle Scholar
  9. Krebs JR, Stephens DW, Sutherland WJ (1983) Perspectives in optimal foraging. In: Brush AJ, Clark GA (eds) Perspectives in Ornithology. Cambridge University Press, pp 165–221Google Scholar
  10. Martin AC, Zim HS, Nelson AL (1951) American Wildlife and Plants. Dover Publications, New YorkGoogle Scholar
  11. Maycock PF (1961) Botanical studies on Mont St. Hilaire, Rouville County, Quebec. General description of the area and floristic survey. Can J Bot 39:1293–1325Google Scholar
  12. Pyke GH, Pulliam HR, Charnov EL (1977) Optimal foraging: a selective review of theory and tests. Quart Rev Biol 52:137–154Google Scholar
  13. Pleasants JM (1981) Bumblebee response to variation in nectar availability. Ecology 62:1648–1661Google Scholar
  14. Robertson C (1928) Flowers and Insects. Science Press Printing Co., Lancaster, PennsylvaniaGoogle Scholar
  15. Rust RW (1977) Pollination in Impatiens capensis and Impatiens pallida (Balsaminaceae). Bull Torrey Bot Club 104:361–367Google Scholar
  16. Waser NM, Price MV (1983) Pollinator behaviour and natural selection for flower colour in Delphinium nelsonii. Nature 302:422–424Google Scholar

Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • G. Bell
    • 1
  • L. Lefebvre
    • 1
  • L. -A. Giraldeau
    • 1
  • D. Weary
    • 1
  1. 1.Biology DepartmentMcGill UniversityMontréalCanada

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