Penny first saw Koko in September 1971 in the San Francisco Zoo. Koko, then just a tiny gorilla was clinging ferociously to her mother. Penny asked the zoo if she could study with Koko, and soon they agreed.
Penny wrote about the foggy Wednesday morning on July 12, 1972 when she was introduced to Koko.
"When I entered the nursery of the Children's Zoo, Koko left the arms of her caretaker, Debbie Lee, for mine. She pushed her soft face close to mine, smelling me and looking me over...I signed, "Hello" (a gesture somewhat like a salute.) Koko put her hand on her head and patted it and then promptly pulled my hair as I sat down."
