Each spring, birds across America are in full voice. Cardinals chatter, sparrows sing and warblers warble. Birdsong lifts the human spirit – “‘Hope’ is the thing with feathers,” after all. Yet birds are not singing to soothe our nerves after a stressful day at the office. Instead, they sing to defend their territories and attract mates.
The traditional view of birdsong focuses on the male bird: He is like a gladiator who fiercely defends his territory against rivals to ensure sufficient space and resources to feed and raise his chicks.
