While singing the same songs as your neighbours may sound
harmonious, research conducted at Queen's University Biological
Station (QUBS) suggests that song-sharing amongst song sparrow
populations is actually an aggressive behavior, akin to flinging
insults back and forth. "It's been hypothesized that repertoire
size and song complexity is about the singer's ability to
advertise their quality as a mate," says lead author Janet
Lapierre, a visiting biologist from the University of Western
Ontario (UWO). "Song-sharing, where birds sing a smaller number
of their species' greatest hits, is a more aggressive and
attention-seeking behaviour. It's also a behaviour most often
displayed by belligerent older males." Ms Lapierre and fellow
QUBS researchers Daniel Mennill (University of Windsor) and Beth
MacDougall-Shackleton (UWO) used a 16-channel acoustic location
system to investigate whether male song sparrows preferentially
choose to sing highly shared song types or whether they use all
song types interchangeably.