Song Sparrow (Image by Becky Matsubara via Flickr CC BY 2.0

Song Sparrow (Image by Becky Matsubara via Flickr CC BY 2.0)

Complexity of a male bird’s song can help attract the most compatible mate, new research suggests. Researchers investigated whether song repertoire and complexity advertises the singer’s genetic dissimilarity to others in the population — something that could help a couple raise the most viable young. A male bird’s health influences how well it can learn complex songs and expand its repertoire. As a result, female birds may be able to evaluate a male’s health by listening to his song: males with attractive and complex songs might have more different types of disease-resistance genes. In the present study, researchers discovered that songbirds with the most complex songs had intermediate rather than maximal numbers of disease-resistance genes.


J. W. G. Slade, M. J. Watson, E. A. MacDougall-Shackleton

Corresponding author:

Elizabeth MacDougall-Shackleton, Department of Biology, Western University, London, ON.  Email:

Original paper published in Biology Letters on November 8, 2017.