It is an observation that had never been made in biology: the song of some birds, the White-throated Sparrows, evolved across a continent from a small localized group, reports Numerama. The phenomenon started in the west of Canada in the 1990s.
Some of these birds slightly modified their song, which ended with three notes. Gradually, their phrasing eventually changed so as to end with two notes. If this development is not particularly rare, notes the specialized media, what is more interesting is the propagation of this modification to birds living several thousand kilometers away.
This new song becomes the norm
“In 2014, all the birds we recorded in Alberta sang this western dialect, and we began to see it appear in populations as distant as Ontario, which is 3,000 kilometers from us”, explains Ken Otter, author of a study on the subject published last Thursday in Current Biology.
The learning of this new dialect would be done through the wintering zones, which are places where birds from different regions meet. “We know that birds sing in the wintering grounds, so young males may be able to pick up new types of songs if they overwinter with birds from other dialect regions,” adds Ken Otter. The new song is now on the verge of supplanting the old, according to observations made.