an epistemological approach to biological kinds

Among the conceptual ingredients of natural kinds, concerning living creatures specially, has been the idea of essentialism. This idea however was challenged by the evolutionary theory in biological world which provided a new view of biological species. In order to analyze the relation between natural kinds and essentialism, I focus on reasons motivated philosophers to invoke the idea of natural kinds and show that this motivation was principally epistemological, i.e. to solve inductive problems. In this view, essentialism, in its strong from, is considered to be a redundant condition for natural kinds,. Essentialism,, in its weaker sense,, is however required, meaning that properties underlying induction must be shared by every individual of a kind, in order to warrant the inductive inference. A consequence of weakening essentialism in natural kinds is the possibility to suggest a unified concept of natural kinds for various sciences, biological and physical.