Movies and television shows 1998 Seinfeld, Season 9, Episode 19 (The Maid); George is nicknamed "Koko the monkey" after co-workers witness him yelling and flailing his arms with a banana in his hand 1998 Mr Rogers' Neighborhood, Episode 1727 (You and I Together); Mister Rogers visits with Koko who has learned how to communicate in sign language 2009 The Big Bang Theory, Season 3, Episode 10 (The Gorilla Experiment); Sheldon makes an attempt to teach physics to Penny, like when Koko learned Sign Language.
Movies and television shows 1998 Seinfeld, Season 9, Episode 19 (The Maid); George is nicknamed "Koko the monkey" after co-workers witness him yelling and flailing his arms with a, banana in his hand: 1998 Mr Rogers' Neighborhood, Episode 1727 (You and I Together); Mister Rogers visits with Koko who has learned how to communicate in sign language 2009 The Big Bang Theory, Season 3, Episode 10 (The Gorilla Experiment); Sheldon makes an attempt to teach physics to Penny, like when Koko learned Sign Language.