Immanuel Kant maintained throughout his life that non-human persons likely exist but he failed to specify how we could recognise them. In this article, I argue (a) that non-human organisms can be considered non-human persons if they can be judged as belonging to a species with a moral vocation, and (b) a species can be judged as having a moral vocation if at least one of its members is able to make what I will call a “moral sacrifice” in which that member sacrifices its physical life for the sake of its moral life.