Then again, look at the rock called granite. It is composed mostly of grains of feldspars and quartz, with some mica and other minerals inserted among them. When granite weathers, the feldspars and micas become clays but nothing much happens to the quartz grains. They are most resistant and get transported down streams or along shores. Thus most beaches are the result of differentially eroded granite. This is an example of natural selection in the nonliving world. Quartz grains survive longer than feldspar grains, and there is a progressive increase in the average resistance to weathering, of the set of grains that have still survived. This action of natural selection is even creative as we see by the formation of a beach. The lack of reproduction imposes constraints on the flexibility of evolution here, but one shouldn't confuse that with the selection itself. We do have here a common sort of evolution by natural selection and there are many other non-living examples.I've made much the same point in my universal selection essay.
Of course, the case for Darwinan physics is quite a bit stronger than this passage implies - because copying and reproduction are also common in the inorganic realm. Rocks split into smaller rocks, streams split into smaller streams, and so on. There's also evidence of family trees - as seen in diffusion limited aggregation, and optimization and exploring a search space - as when a lightning strike finds the highest point in a landscape. However, Van Valen had some of the important ideas quite early on in the history of the field.