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Fig. 8. Proposed core cell lineage of sensory organs in Drosophila and
creation of diversity. Sensory diversity is generated when different processes
are added to this basic pattern of cell division. Two processes may be
distinguished: first, processes in which cell identity is changed without
altering the configuration of the core pattern of cell divisions (red arrows);
and, second, processes in which new complexity is added to this core without
profound modifications in cell identity (blue arrows).