Species as models

This paper argues that biological species should be construed as abstract models, rather than biological or even tangible entities. Various (phenetic, cladistic, biological etc.) species concepts are defined as set-theoretic models of formal theories, and their logical connections are illustrated. In this view organisms relate to a species not as instantiations, members, or mereological parts, but rather as phenomena to be represented by the model/species. This sheds new light on the long-standing problems of species and suggests their connection to broader philosophical topics such as model selection, scientific representation, and scientific realism