Keller & Miller (K&M) propose that many psychiatric disorders are best explained in terms of a genetic watershed model. This view challenges traditional evolutionary accounts of psychiatric disorders, many of which have tried to argue in support of a presumed balanced polymorphism, implying some hidden adaptive advantage of the alleles predisposing people to psychiatric disorders. Does this mean that evolutionary ideas are no longer viable to explain psychiatric disorders? The answer is no. However, K&M's critical evaluation supports the view that psychiatric disorders are not categorically distinct from normalcy, and that evolutionary psychopathology should be grounded in rigorous empirical testing.