First of all, how can we judge an organism whether he knows a language? Language can be divided into different levels and parts, mixing a variety of elements makes a language comes. There are simple words, phrases and idioms etc. Having these language elements, a language can carry out simple and even complex meanings for effective communication. Regarding Koko, she has shown flashes of her brilliance to the world with her ability of using over one thousand signs in daily communication. As the ultimate function of using languages is believed to strike an effective communication, Koko, without a doubt, is meeting the standard! For instance, when Koko was informed that her lovely, beloved kitten, All Ball, was gone, Koko used a couple of signs, which showed her sadness and depression. Demonstrating her understanding in the signs that she used, we can’t say that Koko does not know language. Although Koko is definitely not in our league, there is no way that her potential in language use should be ignored!
Apart from the ability of using simple signs, Koko is capable to show her deep expressions. When you apply a mirror test (scientists put a mirror in front of the animals) to a few organisms, most of them are unable to recognize themselves in the mirror. However, Koko does not shout or fight with the fake self in front of the mirror, she does appreciate and beautify herself indeed. Passing this mirror test,