Aristotle on Essence and Habitat

Despite his awareness that organisms are well suited to the habitats they are typically found in, Aristotle nowhere tries to explain this. It is unlikely that he thinks this “fit” (as I call it) between organisms and their habitats is simply a lucky coincidence, given how vehemently he rejects that as an explanation of the fit between organisms’ various body parts. But it is quite puzzling that Aristotle never explicitly addresses this, since it is a question that seemed so pressing to later philosophers and biologists such as Darwin. In this paper I offer a solution to that puzzle. As I argue, the type of habitat an organism lives in is partly constitutive of its essence or nature. The reason Aristotle does not ask, for instance, why marsh-dweller birds live in marshes, is that it is simply constitutive of their nature that they do so. Given that habitat is built into a kind’s essence, the answer to such a question is obvious and the question would have seemed to him trivial. By attending to the details of his biological treatises, I show that Aristotle’s conception of a living being’s essence is much more nuanced than one can glean from his discussions in the Physics and Metaphysics alone.