Birds of a Feather Sing Together—But Not for the Reasons You Thought!

A groundbreaking new research has turned a hundred-year-old theory on its head for how birds sing in the morning, discovering that sociality, not acoustic environment, is the primary force driving the legendary "dawn chorus."

 

Scientists once believed birds sang early because the cold, still morning air conveyed their song farther, which made it easier to locate a mate or drive off a suitor. But researchers from Cornell University and Project Dhvani in India, using advanced recordings of sound at 43 rainforest locations in the Western Ghats, discovered little to uphold the "acoustic transmission hypothesis.".

 

Instead, they discovered that birds sing most in the morning to promote territory following a night of silence and to negotiate food—especially among very territorial and omnivorous birds. The study, in Philosophical Transactions of the Royal Society B, looked at the song of 69 bird species and discovered 20 of them sang significantly more in the morning than in the evening, with only one species favoring the evening.

 

Key Highlights

 

Social Drivers Rule: Territoriality and diet (more specifically, omnivory) were the best predictors of which birds sang at dawn. Territorial birds employ morning song to signal presence and defend territory, minimizing the necessity of dangerous physical confrontations.

 

Food Coordination: Omnivorous birds, who are typically part of mixed-species foraging groups, sing to coordinate group movement and convey food and predator information.

 

Environmental Variables Dispelled: No meaningful relationship existed between environmental factors such as wind, humidity, or light intensity and dawn song—contrary to decades of assumption.

 

Conservation Tool: Acoustic surveys provide an affordable, real-time way of monitoring bird population and ecological health, offering conservationists in biodiversity hotspots like the Western Ghats a ray of hope.

 

Still Some Mysteries: The researchers further note that more visual observations would be needed to fully make sense of the social forces at play, and some birds, like the dark-fronted babbler, buck the trend by singing more at the beginning of the evening.

 

"Our findings indicate that social factors like diet and territoriality are more important in determining the dawn singing behavior than environmental factors," said lead author Vijay Ramesh.

 

Source: NPR, Earth.com, Phys.org, Times of India, ZME Science, Dynamite News, Karmactive