Bird song – it's not just a male gig
Since Darwin's observations we thought that bird songs were a male trait for courting with females who were drawn to the most seductive male song.
An international study led by the University of Maryland including researchers from the University of Melbourne has upturned this notion of sexual selection and found that female song has also been an important part of the evolution of songbirds.
An author of this study, Dr Michelle Hall from the University's Department of Zoology said, "Female song was overlooked for a long time. In places like the tropics both male and female song birds sing all year round and female bird song is common in Australia."
The study utilised existing global genetic data and aligned it with new data on whether the female song was a feature of various songbird varieties.
"We created an evolutionary tree of songbird species from all over the world including Australasian linages, which we knew would be closer to the 'ancestral' songbirds of the past."
"Not only did 71% of the songbirds we surveyed had female song, but there is a 92% probability that the common ancestor of modern songbirds had female song. So song is not just a male gig, its more complex than originally thought."
Researcher say the long held view of bird song as a male domain, stems back to Darwin's observations in the Northern hemisphere, where female song is less common. This new research, taking advantage of genetics and global data not available to Darwin, suggests the difference between the sexes that he observed is more likely because females in many Northern hemisphere species stopped singing as an evolutionary process, rather than because song only evolved in males."
The results entitled "Female song is widespread and ancestral in songbirds" was published in Nature Communications today, in an international collaboration between the University of Maryland in the US, University of Melbourne in Australia, Leiden University in the Netherlands and The Australian National University.