Greetings. I think the author may be caught in a semantic trap. In a simulated universe, everything is simulated, including “natural” processes. Therefore, there will be some algorithm or equation that describes the process of “natural” selection. One can’t have it both ways (i.e. expect a “natural” process to be natural in a simulated universe).
Still, this is an area of interest for this reader, as one can never really know if we’re all in a simulation of sorts. Our perception is but a collection of interpretations of electrical impulses, right? Who’s to say any of it is “real”? Especially when we consider the strangeness in the quantum realm and the effects the observer has on the observed… :-)