Researchers using 3D-imaging examined a zebra finch's version of the voice box.

London - Birdsong is one of nature’s greatest delights – and scientists believe they may have discovered why.

Songbirds possess a musical instrument more complex than anything found in an orchestra to produce their beautiful sound, they have discovered.

Unlike humans, birds possess two usable pairs of vocal cords allowing them to produce two different notes at the same time, even in flight. While humans and other mammals make sound with their larynx, birds have evolved a unique structure that is located where the windpipe forks to the lungs, known as the syrinx.

Researchers using 3D-imaging examined a zebra finch’s version of the voice box. They discovered how muscles, cartilage and bone work in tandem allowing birds to sing highly intricate songs even on the wing.

Much like humans, birds use sounds to communicate with each other. Different calls can signal their identity or their species and are vital in attracting partners and dealing with predators, as well as educating their young.

Lead scientist Dr Coen Elemans, from the University of Southern Denmark, said songbirds routinely perform while in constant motion.

“Songbirds in particular excel at vocal communication”, said Dr Elemans. “Just imagine an orchestra musician playing his instrument while performing a dance. How do birds do this? We know quite a bit about how the songbird brain codes and decodes songs and how young songbirds learn to imitate the songs of their adult fathers. But we know very little about the instrument itself.

“We used cutting-edge 3D imaging techniques to understand the complicated structure of the vocal organ of songbirds, the syrinx. We show how it is adapted for superfast trills and how it can be stabilised while the bird moves.” The research is published in the online journal BMC Biology. - Daily Mail