Koko, the gorilla who mastered sign language, has died
Koko, the gorilla who mastered sign language and showed the world what great apes can do, has died. She died Tuesday in her sleep at age 46, The Gorilla Foundation said in a statement. "Koko touched the lives of millions as an ambassador for all gorillas and an icon for interspecies communication and empathy," the release said. "She was beloved and will be deeply missed."