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(a) The original life cycle of the organism. There is an adult stage with a fixed number of cells of two types, A and B. Both cell types can produce spores that maintain their epigenetic identity, and can reproduce/differentiate into a new adult. (b) Differentiation graph of the organism. Nodes represent cells of an epigenetic type, arrows represent the possibility for a cell type in the spore to produce another cell type in the adult through replication or differentiation.
