Information has also become a focus of general discussion of evolutionary processes, especially as they relate to the mechanisms of inheritance. One strand of this discussion misconceives information and its role in biological processes. In particular, G.C.  Williams argues that, via reflection on the role of genes in evolution, we can infer that there is an informational “domain” that exists alongside the physical domain of matter and energy (Williams 1992). Richard Dawkins defends a similar view, arguing that the long-term path of evolution is made up of gradual changes in inherited information—as a river that “flows through time, not space” (Dawkins 1995: 4). This is an extension of a more common idea, that there exists such things as “informational genes” that should be understood as distinct from the “material genes” that are made of DNA and localized in space and time (Haig 1997). It is a mistake to think that there are two different things; that there is both a physical entity—a string of bases—and an informational entity, a message. It is true that for evolutionary (and many other) purposes genes are often best thought of in terms of their base sequence (the sequence of C, A, T and G), not in terms of their full set of material properties. This way of thinking is essentially a piece of abstraction (Griesemer 2005). We rightly ignore some properties of DNA and focus on others. But it is a mistake to treat this abstraction as an extra entity, with mysterious relations to the physical domain.