Two articles for you, guys. The first one is about parrots ability to reproduce human sounds and to understand and use human words in a cognitive fashion - the second one is not about parrots but passerines (zebra finches to be exact) but it's VERY interesting in that scientists have discovered that even though birds can learn to vocalize (or sing, in this case) from a different species (in this case, Bengalese finches which 'fostered' the zebra babies), the young birds still use the 'pattern' of song and pause that is typical of their own species. I wonder how that relates to parrots learning human speech...
http://petslady.com/article/parrots-hav ... ady-brains
https://www.sciencedaily.com/releases/2 ... 101055.htm