Allee Award - 2000
This award, named in honor of Warder Clyde Allee, is for the best student paper and presentation in the Allee competition at the annual meeting.
| Song Predicts Cell-mediated and Humoral Immunity in European Starlings, by Deborah Duffy, Johns
Hopkins University | |||
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Administration of testosterone to male starlings resulted in reduced responses of both cell-mediated and
humoral immunity, as predicted. However, T-treatment also elevated the stress hormone corticosterone that has
been demonstrated to be immunosuppressive in some birds and mammals. Therefore, it is possible that what
may appear to be T-induced immunosuppression may in fact be caused by increased corticosterone concentration. In a separate study, behavioralobservations revealed that males who produced more song exhibited enhanced immunity compared to those who rarely sang.Males who sang on average more bouts per hour exhibited greater cell-mediated immunity (r 2 = 0.719) while average song bout length was positively correlated with humoral immunity (r2= 0.388). These data indicate that females who choose males based on their song performance (i.e., singing in longer bouts and at a higher rate) benefit by mating with the most immunocompetent males. |
In my dissertation research, I'm investigating the relationships among song, testosterone, and immunity in a
songbird, the European starling (Sturnus vulgaris). In starlings, song performance by males is key to mating
success as evidenced by males increasing their rate of singing in the presence of a female, and females demonstrating clear preferences for males that sing in longer bouts (Eens, 1997 and
Gentner et al., 2000). My predictions are that 1) T should be immunosuppressive and
2) song characteristics should be positively correlated with immunity when other
factors, such as food availability, activity, and age, are held constant. For these
studies, I measured two components of adaptive immunity, cell-mediated and
humoral. Cell-mediated immunity is important for defense against viral pathogens
(as well as regulating other aspects of the immune system including humoral
immunity) and humoral immunity is important for combating most bacterial
infections. To assess cell-mediated immunity, I injected the harmless plant lectin
phytohemagglutinin (PHA) into the web of skin at the base of the wing to induce a
localized swelling response. I then measured the degree of swelling 24 h and 48 h
later. To assess humoral immunity, I measured antibody responses to injection of the novel antigen, keyhole limpet hemocyanin (KLH) using an enzyme-linked immunosorbant assay (ELISA).