The concept of “animal model” born in the XX century, according to which animals are “models” for experiments on human physiopathology. The scientific basis of this approach lay on evolutionary theory, because it shows that humans and animals are shaped by the same natural laws, in particular that of natural selection. A first application of Darwinism to medicine occurred between 1880 and 1940, in particular in British medicine. Part of the British medical community, adhering to Darwinism, developed the concept that diseases evolved because they were inherited variations. They supported also the continuous evolutionary variations of infectious diseases. Even if many of these assumptions were subsequently abandoned, this early evolutionary medicine favoured the equivalence of animal and human medicine, and therefore the use of animal models in XX century experimental medicine.
