 This is not the place for a history of genetics, which has been offered many times elsewhere. The important point here is that genetics brought a new form of preformationism. Instead of a dynamically acting organism taking its cues from the environmental conditions and from the way that cells interact with each cell division, the twentieth century brought a dominant and popular view that has often emphasized genes as programmed to carry the information of heredity, which was also the information necessary to construct an individual. Of course, there have been calls for alternatives or interactionist models where heredity and development, epigenesis and preformation, work together, but these have often been offered as alternatives than as central interpretations (see  Section 10).