Context-dependent effect of social environment on immune response and sexual signalling in male zebra finches
Deborah J. GleesonSchool of Integrative Biology, University of Queensland, St Lucia, Brisbane, Qld 4072, Australia. Email: dgleeson43@hotmail.com
Australian Journal of Zoology 54(6) 375-379 https://doi.org/10.1071/ZO06001
Submitted: 2 January 2006 Accepted: 20 October 2006 Published: 9 January 2007
Abstract
Variation in avian immune response can be influenced by social environment. This is of particular interest in the context of immunomediated sexual behaviour because social environment may subsequently affect a bird’s relative investment in immunocompetence versus sexual signalling. I tested whether the effect of social environment on immune response and sexual signalling depends on socio-sexual status using male zebra finches (Taeniopygia guttata). To do this, I manipulated social environment (‘same sex’ versus ‘dual sex’) and socio-sexual status (‘high’ versus ‘low’) of the males. I then determined what effect these manipulations had on an index of immunocompetence, namely cell-mediated immune response, and two indices of sexual signalling (bill colour and song rate). I found that social environment influenced cell-mediated immune response and sexual signalling in low-status males. These males had lower immune responses and increased sexual signalling in the dual-sex environment compared with the same-sex environment. In contrast, high-status males had similar immune responses and sexual signalling regardless of social environment. These results suggest that social environment can influence immune response and sexual signalling; however, the nature of this effect was context-dependent, with low-status males more affected than high-status males.
Acknowledgments
I thank I. P. F Owens, M. Blows, R. Whitney, S. Scott, S. Gleeson, D. L. Gleeson and F. Hausmann for their help; the Australian Research Council for funding; The University of Queensland for ethical permission; and the Northern Territory and Queensland governments for collection permits.
Alonso-Alvarez, C. , and Tella, J. L. (2001). Effects of experimental food restriction and body-mass changes on avian T-cell-mediated immune response. Canadian Journal of Zoology 79, 101–105.
| Crossref | GoogleScholarGoogle Scholar |
Saino, N. , and Moller, A. P. (1996). Sexual ornamentation and immunocompetence in the barn swallow. Behavioral Ecology 7, 227–232.
Verhulst, S. , Dieleman, S. J. , and Parmentier, H. K. (1999). A tradeoff between immunocompetence and sexual ornamentation in domestic fowl. Proceedings of the National Academy of Sciences of the United States of America 96, 4478–4481.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
![](../../media/share/OpenURL_Image.gif)
Westneat, D. F. , and Birkhead, T. R. (1998). Alternative hypotheses linking the immune system and mate choice for good genes. Proceedings of the Royal Society of London. Series B. Biological Sciences 265, 1065–1073.
| Crossref | GoogleScholarGoogle Scholar |
![](../../media/share/OpenURL_Image.gif)
Zuk, M. , and Johnsen, T. S. (2000). Social environment and immunity in male red jungle fowl. Behavioral Ecology 11, 146–153.
| Crossref | GoogleScholarGoogle Scholar |
![](../../media/share/OpenURL_Image.gif)
Zuk, M. , and Stoehr, A. M. (2002). Immune defense and host life history. American Naturalist 160, S9–S22.
| Crossref | GoogleScholarGoogle Scholar |
![](../../media/share/OpenURL_Image.gif)