Under what conditions do secondary reproductives develop?

Secondary reproductives in a termite colony develop primarily when the king and queen die. In a typical termite colony, the king and queen are responsible for reproduction, and their presence suppresses the development of other potential reproductive individuals. When these primary reproductives are no longer present, it allows the secondary reproductives to emerge and take over the role of reproduction to ensure the survival and continuation of the colony.

This process is vital for the adaptability and resilience of termite colonies, as it provides a mechanism to maintain population levels even in the face of threats or loss of the dominant reproductive pair. The other conditions presented do not typically lead to the development of secondary reproductives; for example, additional eggs laid by the queen do not trigger their development, nor does the timing of development relate strictly to the age of the colony or seasonality.