On the ontology of biological species

In this paper, two different ontological views concerning biological species are analyzed. On the first view, species are universals instantiated by the members of the species, while, according to the second view, species are complex individuals formed by the members of the species. An alleged decisive argument in favour of the second view is based on the fact that biological species evolve, while abstract entities such as universals cannot change. It is shown that this argument is far from decisive because other kinds of abstract entities such languages are said to evolve. It is, then, illustrated in which sense we can say that abstract entities, such as biological species and languages, change.