A recent trend in Aristotelian scholarship tries to link ethicsm and biology. Within these attempts, some sort of continuity between the character of non-rational animals and that of human beings has been proposed, so that the starting point of moral development could be identified in Aristotle’s description of animal’s character. In this article I argue that this reading should strongly qualified, for understood in some ways it entails a sort of continuity between natural normativity and practical normativity that belongs to an Archimedean ethical naturalism, which cannot be reconstructed from Aristotle’s writings. Connected to this, I argue that the concept of natural virtue is not a natural concept, but an ethical one that only makes sense from within the realm of practical normativity; natural virtue, thus understood, is not part of a genetic (or bottom-up) explanation of virtue, but emerges from a conceptual whole-part analysis. In this manner, natural virtue is no prior, but posterior to ethical vitue.