You know that feeling when you discover a new song, and suddenly everyone’s playing it? Turns out, this doesn’t just happen for humans – a new tune is currently sweeping across the sparrow colonies of Canada.
Like many birds, white-throated sparrows sing to attract a mate. Generally, all males in a particular area will sing the same song, and the females will pick whoever’s version they prefer. However, over the last twenty years, more and more birds having been changing their rhythm.
Originally, this species finished their song with a repeated set of three notes, but this has been replaced by a two-note ending. This variation was first heard in the west of Canada, and has now taken over most of the country.
The birds probably spread the tune during their winter migrations, then take it with them when they travel back for the breeding season. It’s unusual for birds to create new songs, but these sparrows seem to like having something fresh to listen to.
This article was published in Issue 43 of Double Helix magazine (https://www.csiro.au/en/Education/Double-Helix). Copyright for this article is held by CSIRO.
Lachlan Writes Science 