The insect central complex (CX) is a conserved brain region containing 60 + 
neuronal subtypes, several of which contribute to navigation. It is not known 
how CX neuronal diversity is generated or how developmental origin of subtypes 
relates to function. We mapped the developmental origin of four key CX subtypes 
and found that neurons with similar origin have similar axon/dendrite targeting. 
Moreover, we found that the temporal transcription factor (TTF) Eyeless/Pax6 
regulates the development of two recurrently-connected CX subtypes: Eyeless loss 
simultaneously produces ectopic P-EN neurons with normal axon/dendrite 
projections, and reduces the number of E-PG neurons. Furthermore, transient loss 
of Eyeless during development impairs adult flies' capacity to perform celestial 
navigation. We conclude that neurons with similar developmental origin have 
similar connectivity, that Eyeless maintains equal E-PG and P-EN neuron number, 
and that Eyeless is required for the development of circuits that control adult 
navigation.