The main aim of this paper is to provide an account of key metaphors in modern popular genetics. The metaphors under analysis are those of blood-as-carrier-of-heredity, prime mover, Nature as an eternal law-giver or Mother Nature. The author presents an analysis of these metaphors in relation to their origin in the "Great Chain of Being" folk model. The author also explains and traces a distinction between their use in terms of evolution and the Nazi interpretation of heredity, and analyses (a) the reification of a specific biological entity - blood or genes - as an agent of heredity and (b) the reference to some kind of first principle or authority that provides (at least, grammatically) the 'subject' for statements about evolution, as the two main assumptions underlying historical and present-day ways of conceptualising heredity. (Noelia Jiménez Martínez-Losa, Ruiz de Mendoza Group)