LANCASTER, England — Male birds really do need to sing beautiful songs in order to attract mates, but a recent study shows if they’re one-hit wonders, the ladies become bored.
Research completed at Lancaster University and Manchester Metropolitan University in England found that male birds capable of repeating song notes with high precision have a better chance of attracting females.To maintain a female’s interest, males must have a diverse selection of songs in their repertoire.
The findings shed new light on the evolution of bird songs and provide insights into the intricate dynamics of avian courtship.
To understand the significance of song in avian courtship, researchers embarked on a comprehensive two-year study that focused on wild blue tits breeding near Lancaster University. The scientists recorded and analyzed approximately 7,000 songs emanating from closely monitored nest boxes.
The Song Of Bird Love
The experiment designed by the researchers involved playing recorded songs to receptive female blue tits. Findings show that male vocal consistency — the ability to repeat the same pattern of notes with precision — was the key factor that heightened female arousal and excitement.
“Singing in songbirds requires executing complex motor patterns, and precisely hitting those repetitive notes demonstrates to potential mates strong motor skills, which are indicative of essential qualities in a good mate,” lead author Dr. Javier Sierro explained in a media release. He added qualities extend beyond just physical prowess and can include social status, reproductive output, longevity, sexual attractiveness, and the ability to defend territories.
However, there was a catch. While singing exact copies of the same note was found to be attractive to females, it also proved to be monotonous. The female birds’ response gradually declined, a phenomenon known as habituation, until their interest was rekindled when males switched to a different song type or introduced silent pauses between songs.
The study also established a link between vocal consistency and reproductive success, with male blue tits demonstrating higher reproductive success based on the number of eggs in their nests. This finding further supports the notion that vocal consistency is a skill associated with high-quality birds that contribute valuable genes to future populations.
Consistency Is Key
The researchers discovered that vocal consistency increased over the breeding season and peaked during the 7 to 10-day period when the female partner was at her most fertile, laying an egg daily. This suggests that vocal consistency may serve as an indicator of the male’s readiness for reproduction.
Dr. Selvino de Kort, the co-author of the study, says that the results explained why most birds repeat song structures rather than showcase song diversity continuously. “Our results explain why most birds repeat song structures and do not sing in a way that advertises song diversity, by continuously producing novel notes or song types,” Dr. de Kort stated.
The study also addressed a long-standing paradox in bird communication studies by proposing that a balance between vocal consistency and diversity may be responsible for the variability observed in singing styles among bird species.
The study is published in the journal Nature Communications.