Talking Parrot and Funny Talking Birds

Psittacine (the parrot family) and Passerines (the song bird families) use their voices to warn, to court, to communicate with their nestlings and to fight to defend a territory.
The majority of domesticated parrots are only a few generations removed from their wild cousins.
The sounds they make have a huge variation. Some are so pleasant to our ears that Mozart transcribed his pet starling’s voice into music.
Some like the shrieks of the Macaw or the Cockatoo family or some Countries can be extremely unpleasant. In fact I've known Cockatoo owners wear ear muffs!
Wild parrots use sound, whistles, chirps and squawks to communicate. How can the descendants of these same birds modify the sounds into recognizable human sounds? Ongoing research into birds’ vocal abilities and also their sense of rhythm is discovering more and more on this fascinating topic.