I have always been fairly unimpessed with the “linguistic” exploits of our closest genetic relatives, the great apes– the communications chasm seems wider than that between us and our dogs, despite their having been trained to manipulate some symbols.
Which is why recent developments in bird speech and cognition are so mind-boggling, especially as the avian brain is physically extremely different in
its structure. There is a lot of info out there, but check out this BBC
story for a good example of the most talented talking bird, the African gray