 A further issue that dogs any such attempts to explicate the “human” dimension of human nature in terms of developmental programmes inscribed in human DNA concerns Evolutionary Psychologists’ assertion that the programmes are the same in every specimen of the species. This assertion goes hand in hand with the claim that what is explained by such programmes is a deep psychological structure that is common to almost all humans and underlies the surface diversity of behavioural and psychological phenomena (Tooby &amp; Cosmides 1990: 23f.). For Evolutionary Psychologists, the (near-)universality of both developmental programmes and deep psychological structure has an ultimate explanation in evolutionary processes that mark their products as natural in the sense of TP1. Both, they claim, are adaptations. These are features that were selected for because their possession in the past conferred a fitness advantage on their possessors. Evolutionary Psychologists conceive that advantage as conferred by the fulfilment of some specific function. They summarise selection for that function as “design”, which they take to have operated equally on all species specimens since the Pleistocene. This move reintroduces the teleological idea of a fully developed form beyond mere statistical normality (TP3).