Canadian sparrows ditch their old song for catchier tune

Study finds British Columbia birds' dropped-end note of call has spread across country

If you consider Chirpy Chirpy Cheep Cheep to be the ultimate catchy tune, think again: the white-throated sparrows of British Columbia have devised a new song that has gone viral across Canada.

For years, the small songbird's traditional descending whistle featured a three-note ending. But researchers have tracked how a unique two-note-ending version of the male bird's call has rapidly spread 3,000km (1,864 miles) eastwards from western Canada to central Ontario during this century.