The puzzle's not easy to solve.
But now some researchers from Duke
Decided to take a new look.
Some sparrows' loud whistles and trills
They studied, and found that they will
Indeed some new meanings convey,
So their friends will get what they say...
The length of their trills they may change,
And though to our ears it sounds strange,
Where the change is injected depends
On the message the speaker intends.
Like the context of people who speak,
May accomplish, in humans, the trick
Of making the message quite clear
For those who're intended to hear...
Perhaps there will come a new age,
When we will with our wildlife engage
In a friendly and amiable chat,
About the state of the world, and all that...