Recent work in the philosophy of biology has attempted to clarify and defend the use of the biodiversity concept in conservation science. I argue against these views, and give reasons to think that the biodiversity concept is a poor fit for the role we want it to play in conservation biology on both empirical and conceptual grounds. Against pluralists, who hold that biodiversity consists of distinct but correlated properties of natural systems, I argue that the supposed correlations between these properties (...) are not tight enough to warrant treating and measuring them as a bundle. I additionally argue that deflationary theories of biodiversity don’t go far enough, since a large proportion of what we value in the environment falls outside bounds of what could reasonably be called “diversity”. I suggest that in current scientific practice biodiversity is generally an unnecessary placeholder for biological value of all sorts, and that we are better off eliminating it from conservation biology, or at least drastically reducing its role. (shrink)