Experimental inhibition of a key cellular antioxidant affects vocal communication

1.There is substantial interest of evolutionary ecologists in the proximate mechanisms that modulate vocal communication. In recent times, there has been growing interest in the role of oxidative stress as a mediator of avian song expression.

2.Here we tested whether the experimental inhibition of the synthesis of a key cellular antioxidant (glutathione) reduces song rate metrics of male European starlings (Sturnus vulgaris). We measured the effect of our treatment on total song rate and on its two components, undirected and nest-box oriented song, outside the breeding season.

3.Treated males that did not own a nest-box (subordinate males likely to be of lower quality) suffered increased oxidative stress relative to untreated males, while treated males that owned a nest-box (dominant males likely to be of higher quality) did not. Treated non-owners also reduced their undirected song rate, whereas treated nest-box owners did not suffer any reduction in song rate.

4.Our results r...