Song and hearing in different canary strains (Serinus canarius)

Canaries have been selectively bred for specific song characteristics (song canaries) or for morphology or plumage (type canaries) for centuries. Type canaries (e.g., Border and Gloster strains) retain song characteristics that are quite similar to those of wild canaries. By contrast, song canaries (e.g., Belgian Waterslager and Roller strains) have been selected for song types pleasing to the human ear, resulting in songs that, in most cases, are less complex, lower-pitched, and narrower in a frequency range than songs from wild canaries. We now suspect that song selection in the Belgian Waterslager song canary has either directly or indirectly resulted in high-frequency hearing loss associated with hair cell abnormalities. Here, we compare hearing in the Belgian Waterslager and several other type and song canaries including the American Singer Canary. Though bred only since the 1930s, American Singer canaries may also have a high-frequency hearing loss that looks very similar to that of the Belgian Waterslager and may involve similar pathologies. Illumina whole-genome sequencing has preliminarily identified a number of high-impact SnpEff variants in Belgian Waterslager and American Singer Canaries, some of which are related to deafness genes in mammals.