““The theory behind primate experimentation was that these animals were closer biologically to man. In the 1950's, several laboratories even attempted experiments on gorillas, going to great trouble and expense to work with these seemingly most human of animals. However, by 1960 it had been demonstrated that of the apes, the chimpanzee was biochemically more like man than the gorilla. (On the basis of similarity to man, the choice of laboratory animals is often surprising. For example, the hamster is preferred for immunological and cancer studies, since his responses are so similar to man's, while for studies of the heart””
