One of the debates about the Anthropocene is about just how precisely the term should be used. In a post this week at the Anthropocene Review blog Clive Hamilton complains about the imprecision he sees in the controversy over dating the onset of the Anthropocene. He argues that the more or less superficial (even if spatially extensive) landscape changes due to early agriculture do not have the globally systemic impact required for the demarcation of a geological period; he seems to think there is something intellectually sloppy in the “mission creep” that seems to have attached to the term “Anthropocene,” whereby it is applied to anything that shows a trace of human influence. I don’t want to address the substance of his post here, though. Rather, I want to suggest something about why there is such uptake of the word—why it might be that people across disciplines want to use it.

I hope I am not being too reductive by suggesting that the term Anthropocene is appealing because it is a vivid expression of hybridity. It pairs ideas which seem diametrically apart—humanity and geology, not to say culture and nature—and posits a third, hybrid, entity constituted by their interaction, which can’t be adequately characterized in terms of one side or the other.¹ For people disposed to seeing the world in terms of hybrids (I hope not just as a matter of intellectual fashion!) the Anthropocene looks like a planetary-scale example of what they see at lesser scales. Invoking the name thus invokes, as it were, a world-view, in which hybridity plays a central conceptual role.

Such a world view might be a matter of purely philosophical commitments. But within the field of Biology there is an increasing appreciation of the extent of hybridity. This was the topic of an article by Moises Velasquez-Manoff in last Sunday’s New York Times, “Should You Fear the Pizzly Bear?” The story describes the emergence of fertile hybrids of different species of bears (mixing polar and grizzly) and canines (mixing coyotes, wolves, and dog), among other cases.² One lesson I took from the article was that rather than being monstrous, the crossing of boundaries set by nature (in the form of distinct species), hybridization is at minimum a natural response to certain environmental stresses (some anthropogenic), and perhaps, more, is found even under normal circumstances. This suggests that the belief that species boundaries are rigid, marking distinct natural kinds, is an imposition of a somewhat rigid conceptual scheme on a somewhat fluid nature—a nature in which things don’t always stay within their categories.

It seems entirely appropriate to me, therefore, to discuss the Pizzly Bear under the rubric of the Anthropocene (this is not to say that Hamilton would or would not countenance such a discussion). On the one hand, the environmental pressures that are leading to that particular hybridization are certainly anthropogenic, and indeed directly associated with the formal Anthropocene proposal. But on the other, it (and the other examples in the story) reflect the very same kind of reality the Anthropocene does: a reality that is the product of interaction. Perhaps it is appropriate to approach the study of the Anthropocene in that same spirit, i.e. to see the Anthropocene not as an object of study constituted by a single discipline, but as an intellectual hybrid constituted by interdisciplinary cross-fertilization.