CANADA:The number of different songs a bird can sing is a good indicator of its health, according to a new study. Scientists have found that male sparrows with big song repertoires have larger brains and stronger immune systems and are in overall better shape than their less talented counterparts.
Scientists have long suspected that the number of songs a male bird is capable of singing can signal his suitability as a mate. Previous research has shown that males with complex song repertoires find mates earlier in the breeding season.
Researchers from the University of Western Ontario analysed more than 500 songs from more than 70 male sparrows and correlated the complexity of the singing with a range of physical characteristics. They also measured the size of the birds' HVC, the part of the bird brain mainly responsible for singing.
Prof Jeremy Pfaff said that complex birdsong was a good example of an ornamental trait used in sexual selection, the acoustic equivalent of a peacock's tail. "In many species, females prefer males with large song repertoires, possibly because repertoire size is limited by the size of song-control nuclei [ in the brain], which reflect developmental success." - (Guardian Service)