Partial Sex-Role Reversal of the Pink Bollworm Moth (Pectinophora gossypiella)

Complete and partial sex role reversals, where males are selective and females compete, are common in species in which males contribute more than just sperm to reproduction. In the Lepidoptera order, and particularly in the pink bollworm moth, both sexes invest significantly in reproduction. Therefore, we hypothesized that both females and males would exhibit some degree of mate selectiveness. Our study found that males delayed mating with smaller, less fecund females when larger, more fecund females were present in their surroundings. In contrast, males raised without exposure to females mated indiscriminately with both large and small females. Additionally, larger, more fecund females were more selective than their smaller, less reproductive counterparts. Even though large females exhibited greater selectiveness than small females, their selectiveness appears to be an indirect form of mate choice, as they did not choose based on the males’ size but rather rejected a higher number of males overall.