In what terms should we think of these beings, nonhuman yet possessing so very many human-like characteristics? How should we treat them? Surely we should treat them with the same consideration and kindness as we show to other humans; and as we recognize human rights, so too should we recognize the rights of the great apes? Yes.
"The Great Ape Project: Equality Beyond Humanity". Book by Paola Cavalieri, Peter Singer, 1996.