Koko is a gorilla who knows sign language.
Koko understands approximately 2,000 words of spoken English, in addition to the signs. Koko is able to understand more than 1,000 signs of what Patterson calls "Gorilla Sign Language".
Francine "Penny" Patterson
This is Koko's trainer, and the one who the care taker.
Koko loves cat its her favorite animal.
Another cat of Koko's
She's had several cats, and she acts like a mother toward them.