Culture and Propagation of Laboratory Populations of the African Butterfly Bicyclus anynana

Abstract

INTRODUCTIONThis protocol describes methods required for the culture of the African butterfly Bicyclus anynana. The larvae are typically fed and maintained on pot-grown maize plants (Zea mays) that are ~50 cm high. Males and females can be separated as pupae or adults. Adults are fed on moist banana and will readily mate in the laboratory. Females lay eggs on available grass plants. We use a standard temperature of 27°C (because an approximate rule is that developmental time is twice as long at 20°C), a high relative humidity of ~60%-70% (the exact level is not critical), and a 12:12 photoperiod similar to the climate experienced in the wet season near the equator. Both larval and pupal molts are gated by photoperiod and can be readily timed (e.g., by use of time-exposure filming). To set up cohorts of standard developmental stages, an appropriate timing for this photoperiod is chosen: Pupation usually occurs shortly after lights out, and larval molts also occur during the night. At ~27°C, egg development takes 4 d, and the total generation time is 5-6 wk, yielding about eight generations a year in selection experiments.