Wakefield's evolutionary dysfunction account of disease is too restrictive because it excludes illnesses arising from biological structures with no evolved function

An evolutionary approach faces problems in specifying what the overall evolved function of a system might be and showing how functions contribute to it. First, it is very difficult to assess the relevant evidence that a given biological systems is — as in Wakefield’s treatment — the product of natural selection (Davies 2001, Chapter 5). Since many ailments do not prevent one from living and having children, it is even harder to show that a disease is necessarily the product of a malfunction that