Jane Goodall spent months living near the chimpanzees in the Gombe National Park of Tanzania. She went slowly and eventually the chimps began to trust the long-haired pink primate. While she may not have followed strict scientific protocols in her studies, Goodall's observations humanized our nearest cousins. She changed the way we think of the chimpanzees, and the way we think about ourselves.
This image in particular shows that link between humans and chimpanzees. Curiosity and trust shows on both of their faces. Two distant cousins meeting for the first time. Just amazing.