Yes, Capfka, that it what i have heard/read-- Koko, (and other great apes), seem to be able to use language, to make up words to express new ideas, (re: The big thing (in relation to this thread) is that she compounds signs she knows to create new words when she wants them. She saw someone with an ice lolly once and was given a piece. She liked it, and asked for one. She didn't have the sign, so she combined "cold" and "stick".,
birds show the ability to learn colors, nuumbers, shapes and other human constructs, but never to make up new ideas. a myhna might learn to say "ice cream' or "ice lolly", but its seems they would never think up "cold stick"--Koko, (and other apes) don't have the right shape mouth or throat to be able to make all the sounds humans make... but with sign language, it is clear they are able to understand and use language.
Myhnas can express noises that humans make, and can even associate some noises with concepts.. (three red stars) but if you crossed triange over another, (to make a 6 pointed star, they wouldn't call it triangle star, or new star or big star (vs a 5 pointed star) its not even clear if they would recognize it as a star shape. Apes would. they would grok the pointiness as a characteristic of "stars", and realize a six pointed is not the same as star(five pointed) but still 'starlike"
