Koko demonstrates levels of awareness similar to humans.
Koko is looking at a sign language dictionary and points to the sign “wet” in the book. Penny tries to explain the sign to Koko. Then Penny notices that Koko’s tongue is “brilliant pink” (Koko had been drawing with non-toxic marker pens, which she tried to taste). To show Koko how pink her tongue is, Penny brings a mirror. Koko is quite adept at using mirrors, and after looking at her tongue, notices that she has glitter on her nose, tries to remove it, and then examines her tongue again (signing “red frown-mouth frown-red”).
It used to be thought that only humans could recognize themselves in mirrors, and display self-awareness. Thanks to studies like Project Koko, we now know that all great apes have this ability.