The difference between a Nightingale and a Chicken is just not their voice alone. Looks like there is more to it. In an article about songbirds, the author explains why some are special than the other.
“Vocal patterns are hardwired in animals like chicken and frogs because they do not have to hear to be able to vocalize” remarks Dr. Ofer Tcernichovski
A nightingale, the Mozart or MS Subbulakshmi among the avians, on the other hand, has over 200 different songs in its repertoire. And it can improvise. First it might sing the note sequence ABCDEF and a while later it might sing BEDF
And it doesn't stop there.
Songbirds, just as humans, learn from listening and the younger ones learn and create more music than the older ones. Analysis of the brain circuitry (neuro-anatomy) of some songbirds shows a remarkable similarity with those of we humans.
It makes me wonder if it is from the nature humans learned to identify musical notes and its compositions.
Probably nature was the first teacher.
Thanks to wikimedia, you can listen to a song of Nightingale here
The full article on songbirds is here.