Weel May The Keel Row

In the 1930s in Dorrigo, New South Wales, a flute-playing farmer kept a young lyrebird as a pet for several years. In all that time the bird learned to imitate just one small fragment of the farmer's flute-playing ... the farmer released the bird into the forest. Thirty years later, lyrebirds in the adjacent New England National Park were found to have flute-like elements in their song, a sound not heard in other populations of superb lyrebirds. Further analysis of the song showed that the phrase contained elements of two popular tunes of the 1930s, "Mosquito Dance" and "The Keel Row". As lyrebirds can sing two melodies simultaneously, through several generations this population had created its own distinctive territorial song blending the two melodies into a single compressed phrase ... it is now seventy years since the lyrebird learned these fragments, and today the flute song has been heard a hundred kilometres from the original source. A human song is spreading through the lyrebird world ...

from : Why Birds Sing by David Rothenberg, Allen Lane, 2005