Abstract
The strength of selection on immune function in wild populations has only been examined in a few vertebrate species. We report the results from a study measuring selection on a key insect immune enzyme, phenoloxidase (PO), in a wild population of the damselfly Calopteryx xanthostoma. We followed individually marked males from the pre-reproductive adult phase and recorded their lifetime mating success. We found positive selection on PO activity in response to an immune insult, but no selection on wing-spot quality, a trait actively displayed to females during courtship. We suggest that positive selection on PO activity in the year of study may be explained by annual fluctuations in parasite loads.
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Selected References
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- Behnke J. M., Barnard C. J., Wakelin D. Understanding chronic nematode infections: evolutionary considerations, current hypotheses and the way forward. Int J Parasitol. 1992 Nov;22(7):861–907. doi: 10.1016/0020-7519(92)90046-n. [DOI] [PubMed] [Google Scholar]
- Finch C. E., Rose M. R. Hormones and the physiological architecture of life history evolution. Q Rev Biol. 1995 Mar;70(1):1–52. doi: 10.1086/418864. [DOI] [PubMed] [Google Scholar]
- Gillespie J. P., Kanost M. R., Trenczek T. Biological mediators of insect immunity. Annu Rev Entomol. 1997;42:611–643. doi: 10.1146/annurev.ento.42.1.611. [DOI] [PubMed] [Google Scholar]
- Hoekstra H. E., Hoekstra J. M., Berrigan D., Vignieri S. N., Hoang A., Hill C. E., Beerli P., Kingsolver J. G. Strength and tempo of directional selection in the wild. Proc Natl Acad Sci U S A. 2001 Jul 24;98(16):9157–9160. doi: 10.1073/pnas.161281098. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rolff J., Siva-Jothy M. T. Invertebrate ecological immunology. Science. 2003 Jul 25;301(5632):472–475. doi: 10.1126/science.1080623. [DOI] [PubMed] [Google Scholar]
- Råberg Lars, Stjernman Martin. Natural selection on immune responsiveness in blue tits Parus caeruleus. Evolution. 2003 Jul;57(7):1670–1678. doi: 10.1554/02-417. [DOI] [PubMed] [Google Scholar]
- Saino N., Bolzern A. M., Møller A. P. Immunocompetence, ornamentation, and viability of male barn swallows (Hirundo rustica). Proc Natl Acad Sci U S A. 1997 Jan 21;94(2):549–552. doi: 10.1073/pnas.94.2.549. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schmid-Hempel Paul. Variation in immune defence as a question of evolutionary ecology. Proc Biol Sci. 2003 Feb 22;270(1513):357–366. doi: 10.1098/rspb.2002.2265. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Siva-Jothy M. T. A mechanistic link between parasite resistance and expression of a sexually selected trait in a damselfly. Proc Biol Sci. 2000 Dec 22;267(1461):2523–2527. doi: 10.1098/rspb.2000.1315. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sugumaran Manickam. Comparative biochemistry of eumelanogenesis and the protective roles of phenoloxidase and melanin in insects. Pigment Cell Res. 2002 Feb;15(1):2–9. doi: 10.1034/j.1600-0749.2002.00056.x. [DOI] [PubMed] [Google Scholar]