Conceptualisation of insecticide selection over multiple gonotrophic cycles.

1): The number of females in each subsequent cycle decreases due to insecticide killing (e.g., ) and natural survival (). This results in fewer eggs being laid in subsequent cycles. 2): As a result of insecticide selection, surviving females have a higher mean PRS than the previous cycle as only resistant individuals would be able to survive multiple insecticide encounters. 3): An increasing mean PRS of females gives an increased female insecticide selection differential (height of blue bars). The male selection differential (height of red bars) remains constant as female mosquitoes mate only once. 4): As the female selection differential increases, the response increases. Eggs laid by females in subsequent cycles produce more resistant individuals. The updated mean PRS for the next generation is the mean PRS of the eggs laid over all the cycles.